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Wheeler MA, Govindasamy LS. Women in medical leadership: has the COVID-19 crisis heightened the glass cliff? Med J Aust 2024; 220:352-354. [PMID: 38415393 DOI: 10.5694/mja2.52242] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2023] [Accepted: 11/20/2023] [Indexed: 02/29/2024]
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2
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Wheeler MA, Wilson SG, Baes N, Demsar V. A search for commonalities in defining the common good: Using folk theories to unlock shared conceptions. Br J Soc Psychol 2024; 63:956-974. [PMID: 38168870 DOI: 10.1111/bjso.12713] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2023] [Accepted: 12/03/2023] [Indexed: 01/05/2024]
Abstract
Throughout the course of scholarly history, some concepts have been notoriously hard to define. The 'common good' is one such concept. While the common good has a long and contested scholarly history, social psychology research on folk theories - lay beliefs that represent an individual's informal and subjective understanding of the world - may provide a key for unlocking this nebulous concept. In the current paper, we analysed lay definitions of the common good using the linguistic inquiry and word count's meaning extraction method. From a nationally representative Australian sample of open-ended text responses (n = 14,303), we uncovered a consistent conceptual structure, with nine themes corresponding to three core aspects: (i) outcomes and objects, (ii) principles and processes and (iii) stakeholders and beneficiaries. From this, we developed a working definition of the folk concept of the common good: 'achieving the best possible outcome for the largest number of people, which is underpinned by decision-making that is ethically and morally sound and varies by the context in which the decisions are made'. A working definition benefits the academic community and society more broadly, particularly when diverse stakeholders come together to act for the common good to address shared challenges.
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Affiliation(s)
- Melissa A Wheeler
- Graduate School of Business and Law, RMIT University, Melbourne, Victoria, Australia
| | - Samuel G Wilson
- Department of Management and Marketing, Swinburne University of Technology, Melbourne, Victoria, Australia
| | - Naomi Baes
- Department of Management and Marketing, Swinburne University of Technology, Melbourne, Victoria, Australia
- Melbourne School of Psychological Sciences, The University of Melbourne, Melbourne, Victoria, Australia
| | - Vlad Demsar
- Department of Management and Marketing, Swinburne University of Technology, Melbourne, Victoria, Australia
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Wong LY, Wheeler MA. Relax into the tension: Paradoxes experienced by emerging leaders in emergency medicine. Emerg Med Australas 2023. [PMID: 37321844 DOI: 10.1111/1742-6723.14266] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2023] [Accepted: 06/06/2023] [Indexed: 06/17/2023]
Affiliation(s)
- Lee Yung Wong
- Emergency Department, Austin Health, Melbourne, Victoria, Australia
- School of Business, Law and Entrepreneurship, Swinburne University of Technology, Melbourne, Victoria, Australia
| | - Melissa A Wheeler
- School of Business, Law and Entrepreneurship, Swinburne University of Technology, Melbourne, Victoria, Australia
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Oldmeadow JA, Elphinstone B, Sivasubramaniam D, Wheeler MA, Wilson S, Buzwell S, Beaudry J, Williams JS, Critchley C. Classifying Australian citizens' responses to
COVID
‐19 preventative behaviour directives: A latent class approach. Community & Applied Soc Psy 2023. [DOI: 10.1002/casp.2691] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/18/2023]
Affiliation(s)
- Julian A. Oldmeadow
- Department of Psychological Sciences Swinburne University of Technology Hawthorn Victoria Australia
| | - Bradley Elphinstone
- Department of Psychological Sciences Swinburne University of Technology Hawthorn Victoria Australia
| | - Diane Sivasubramaniam
- Department of Psychological Sciences Swinburne University of Technology Hawthorn Victoria Australia
| | - Melissa A. Wheeler
- Department of Management and Marketing Swinburne University of Technology Hawthorn Victoria Australia
| | - Sam Wilson
- Department of Management and Marketing Swinburne University of Technology Hawthorn Victoria Australia
| | - Simone Buzwell
- Department of Psychological Sciences Swinburne University of Technology Hawthorn Victoria Australia
| | - Jennifer Beaudry
- Department of Psychological Sciences Swinburne University of Technology Hawthorn Victoria Australia
| | - James S. Williams
- Department of Psychological Sciences Swinburne University of Technology Hawthorn Victoria Australia
| | - Christine Critchley
- Department of Psychological Sciences Swinburne University of Technology Hawthorn Victoria Australia
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Wheeler MA, Vylomova E, McGrath MJ, Haslam N. More confident, less formal: stylistic changes in academic psychology writing from 1970 to 2016. Scientometrics 2021. [DOI: 10.1007/s11192-021-04166-9] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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Kaufmann LM, Wheeler MA, Sojo VE. Employment Precarity Strengthens the Relationships Between the Dark Triad and Professional Commitment. Front Psychol 2021; 12:673226. [PMID: 34354634 PMCID: PMC8329547 DOI: 10.3389/fpsyg.2021.673226] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2021] [Accepted: 05/31/2021] [Indexed: 11/23/2022] Open
Abstract
The Dark Triad traits of Machiavellianism, narcissism, and psychopathy have been found to negatively impact work behaviors including information sharing, reporting of unethical conduct, and mistreatment of colleagues and subordinates. However, research has found the Dark Triad can also be related to forms of organizational commitment which underpin positive work behaviors, including engaging in tasks and duties beyond those required (i.e., “going above and beyond”). Professional commitment is a broader form of commitment that has been found to be significantly related to organizational commitment, sharing antecedents, and having similar outcomes. Professional commitment, the affective, normative, and continuance commitment toward one's profession or occupation, has the benefit of applying to individuals employed by organizations as well as those working for themselves or between jobs. In this research, we explore relationships between professional commitment, using previous research on the relationship between the dark triad traits of Machiavellianism, psychopathy, and narcissism and organizational commitment, as a basis for predictions. We also explored two forms of precarious employment (career interruptions and part-time or casual work) as possible moderators of the dark triad-professional commitment relationship. Participants were 184 Australian professionals (52.2% men), a slight majority of whom had experienced a career interruption (69.6%) or a year or more of part-time or casual employment (70.7%). The results showed that psychopathy had a negative association with affective commitment, whereas Machiavellianism was positively related to normative commitment, and narcissism was positively related to normative and continuance commitment. Using regression analysis, we found that among individuals who have worked in part-time/casual employment longer, Machiavellianism and psychopathy had significantly stronger negative associations with affective commitment. In contrast, among individuals who have had a significant career interruption, Machiavellianism had significantly stronger positive association with continuance commitment. These findings help expand our understanding of both the dark triad and its contingent impact on workers' attachment to their profession.
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Affiliation(s)
- Leah M Kaufmann
- School of Behavioural and Health Sciences, Faculty of Health Sciences, Australian Catholic University, Sydney, NSW, Australia
| | - Melissa A Wheeler
- Department of Management and Marketing, Swinburne Business School, Swinburne University of Technology, Hawthorn, VIC, Australia
| | - Victor E Sojo
- Department of Management and Marketing, Faculty of Business and Economics, The University of Melbourne, Parkville, VIC, Australia
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Pless NM, Sengupta A, Wheeler MA, Maak T. Responsible Leadership and the Reflective CEO: Resolving Stakeholder Conflict by Imagining What Could be done. J Bus Ethics 2021; 180:313-337. [PMID: 34177017 PMCID: PMC8219517 DOI: 10.1007/s10551-021-04865-6] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 08/28/2020] [Accepted: 06/03/2021] [Indexed: 06/13/2023]
Abstract
In light of grand societal challenges, most recently the global Covid-19 pandemic, there is a call for research on responsible leadership. While significant advances have been made in recent years towards a better understanding of the concept, a gap exists in the understanding of responsible leadership in emerging countries, specifically how leaders resolve prevalent moral dilemmas. Following Werhane (1999), we use moral imagination as an analytical approach to analyze a dilemmatic stakeholder conflict (between indigenous communities in rural India and an emerging market multinational enterprise headquartered in the same country) through the lense of different responsible leadership mindsets and in light of different ethical principles and moral background theories. Based on this analysis, we arrive at a tentative moral judgement, concluding that the instrumental approach is morally inferior and recommending the integrative approach as the morally superior choice. In the subsequent discussion-focussed on what "could" (instead of "should") be done, we apply the integrative script and use moral imagination as a pathway for generating morally justifiable solutions. Through this analysis, we provide novel insights on how to apply an integrative responsible leadership approach to a stakeholder conflict situation, using the single case study to expand the responsible leadership discussion to emerging markets.
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Affiliation(s)
- Nicola M. Pless
- Professor of Management, Chair in Positive Business, Director Centre for Business Ethics & Responsible Leadership, University of South Australia, UniSA Business, North Terrace, Elton Mayo Building, Adelaide, SA 5000 Australia
| | - Atri Sengupta
- Assistant Professor, Area Chair, OB & HR, Indian Institute of Management Sambalpur, Sambalpur, Odisha - 768019 India
| | - Melissa A. Wheeler
- Senior Lecturer, Faculty of Business and Law, Swinburne University of Technology, John St, Hawthorn, VIC 3122 Australia
| | - Thomas Maak
- Professor of Leadership, Director Centre for Workplace Leadership, University of Melbourne, 198 Berkeley Street, Melbourne, VIC 3010 Australia
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Haslam N, Dakin BC, Fabiano F, McGrath MJ, Rhee J, Vylomova E, Weaving M, Wheeler MA. Harm inflation: Making sense of concept creep. European Review of Social Psychology 2020. [DOI: 10.1080/10463283.2020.1796080] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Affiliation(s)
- Nick Haslam
- Melbourne School of Psychological Sciences, University of Melbourne, Melbourne, Australia
| | - Brodie C. Dakin
- Melbourne School of Psychological Sciences, University of Melbourne, Melbourne, Australia
| | - Fabian Fabiano
- Melbourne School of Psychological Sciences, University of Melbourne, Melbourne, Australia
| | - Melanie J. McGrath
- Melbourne School of Psychological Sciences, University of Melbourne, Melbourne, Australia
| | - Joshua Rhee
- Melbourne School of Psychological Sciences, University of Melbourne, Melbourne, Australia
| | - Ekaterina Vylomova
- Melbourne School of Psychological Sciences, University of Melbourne, Melbourne, Australia
| | - Morgan Weaving
- Melbourne School of Psychological Sciences, University of Melbourne, Melbourne, Australia
| | - Melissa A. Wheeler
- Department of Management and Marketing, Swinburne University of Technology, Melbourne, Australia
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McGrath MJ, Randall-Dzerdz K, Wheeler MA, Murphy S, Haslam N. Concept creepers: Individual differences in harm-related concepts and their correlates. Personality and Individual Differences 2019. [DOI: 10.1016/j.paid.2019.04.015] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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Abstract
Trends in the cultural salience of morality across the 20th century in the Anglophone world, as reflected in changing use of moral language, were explored using the Google Books (English language) database. Relative frequencies of 304 moral terms, organized into six validated sets corresponding to general morality and the five moral domains proposed by moral foundations theory, were charted for the years 1900 to 2007. Each moral language set displayed unique, often nonlinear historical trajectories. Words conveying general morality (e.g., good, bad, moral, evil), and those representing Purity-based morality, implicating sanctity and contagion, declined steeply in frequency from 1900 to around 1980, when they rebounded sharply. Ingroup-based morality, emphasizing group loyalty, rose steadily over the 20th century. Harm-based morality, focused on suffering and care, rose sharply after 1980. Authority-based morality, which emphasizes respect for hierarchy and tradition, rose to a peak around the social convulsions of the late 1960s. There were no consistent tendencies for moral language to become more individualist or less grounded in concern for social order and cohesion. These differing time series suggest that the changing moral landscape of the 20th century can be divided into five distinct periods and illuminate the re-moralization and moral polarization of the last three decades.
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Affiliation(s)
- Melissa A. Wheeler
- Department of Management and Marketing, Faculty of Business and Economics, University of Melbourne, Victoria, Australia
- Melbourne School of Psychological Sciences, Faculty of Medicine, Dentistry and Health Sciences, University of Melbourne, Victoria, Australia
| | - Melanie J. McGrath
- Melbourne School of Psychological Sciences, Faculty of Medicine, Dentistry and Health Sciences, University of Melbourne, Victoria, Australia
| | - Nick Haslam
- Melbourne School of Psychological Sciences, Faculty of Medicine, Dentistry and Health Sciences, University of Melbourne, Victoria, Australia
- * E-mail:
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11
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Abstract
Wax esters, isolated fromTetrahymena pyriformis, have been found to contain 45% branched chain alcohols and 76% branched chain fatty acids. No esters of tetrahymanol or of sterols were found.
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Affiliation(s)
- M A Wheeler
- Department of Chemistry, University of Maryland, 20742, College Park, Maryland
| | - C E Holmlund
- Department of Chemistry, University of Maryland, 20742, College Park, Maryland
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12
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Wheeler MA, Laham SM. What We Talk About When We Talk About Morality: Deontological, Consequentialist, and Emotive Language Use in Justifications Across Foundation-Specific Moral Violations. Pers Soc Psychol Bull 2016; 42:1206-16. [PMID: 27340149 DOI: 10.1177/0146167216653374] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2015] [Accepted: 05/15/2016] [Indexed: 11/15/2022]
Abstract
Morality is inherently social, yet much extant work in moral psychology ignores the central role of social processes in moral phenomena. To partly address this, this article examined the content of persuasive moral communication-the way people justify their moral attitudes in persuasive contexts. Across two studies, we explored variation in justification content (deontological, consequentialist, or emotive) as a function of moral foundations. Using justification selection techniques (Study 1) and open-ended justification production (Study 2), results demonstrate a preference (a) for deontological appeals in justifications for the sanctity foundation, (b) for consequentialist appeals for the individualizing foundations (care and fairness), and (c) for emotive appeals in justifications for the binding foundations (loyalty, authority and sanctity). The present research questions the generality of inferences about the primacy of emotions/intuition in moral psychology research and highlights the important role of reasons in persuasive moral communication.
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Sojo VE, Wood RE, Wood SA, Wheeler MA. Reporting requirements, targets, and quotas for women in leadership. The Leadership Quarterly 2016. [DOI: 10.1016/j.leaqua.2015.12.003] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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Abstract
STUDY DESIGN Retrospective chart review. OBJECTIVES To determine the prevalence of fatigue in an outpatient spinal cord injury population and to examine the clinical variables contributing to that fatigue. SETTING GF Strong Rehabilitation Centre, Vancouver, British Columbia, Canada. METHODS Medical charts of 76 individuals admitted to the GF Strong Outpatient SCI Program between December 2004 and December 2005 were reviewed. Data collected included information on clinical characteristics, demographics and Fatigue Severity Scale (FSS) scores. Multivariable analysis was completed to determine the independent association between these variables and fatigue severity. RESULTS A total of 57% (95% confidence interval (CI)=45-67%) of the sample were found to have fatigue severe enough to interfere with function. People that were admitted for medical reasons; had pain, spasticity, incomplete injuries, and/or were on more that one medication with a known side effect of fatigue had significantly higher FSS scores. Multivariable analysis indicated incomplete injury was the only statistically significant predictor of a higher FSS scores; pain approached significance (P=0.07, CI=-0.09, 2.06). Together these variables account for 18% of the variance in FSS scores in this sample. CONCLUSION Fatigue among individuals with spinal cord injury who are seeking outpatient rehabilitation is very common. The severity of fatigue was greater for individuals with incomplete lesions. Pain was also a potentially important covariate of fatigue. Further research is required to determine what else contributes to fatigue severity beyond these clinical variables as only minimal variance was accounted for in our model.
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Affiliation(s)
- T M Fawkes-Kirby
- School of Rehabilitation Sciences, University of British Columbia, Vancouver, British Columbia, Canada
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15
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Abstract
In follicular lymphomas with the t(14;18) translocation, there is increased expression of the bcl-2 gene, which is dependent upon regulatory elements within the bcl-2 5' flanking region and the immunoglobulin heavy-chain gene enhancers. We found that t(14;18) lymphomas expressed C/EBPalpha, which is not normally expressed in B lymphocytes. Expression of C/EBPalpha increased bcl-2 expression, and two regions of the bcl-2 P2 promoter that mediated this effect were identified. C/EBPbeta was also able to increase bcl-2 promoter activity through these sites. The 5' site was GC-rich and did not contain a C/EBP consensus sequence; however, C/EBP was observed to interact with this site both in vitro by EMSA and in vivo by chromatin immunoprecipitation assay. The 3' region contained the Cdx site, which mediates the effect of A-Myb on the bcl-2 promoter. In vivo binding studies revealed that C/EBP interacted with this region of the bcl-2 promoter as well. Decreased expression of C/EBP factors due to targeting of their transcripts by siRNA molecules resulted in downregulation of Bcl-2 protein. We conclude that C/EBPalpha and C/EBPbeta contribute to the deregulated expression of Bcl-2 in t(14;18) lymphoma cells.
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MESH Headings
- B-Lymphocytes/pathology
- B-Lymphocytes/physiology
- Base Composition
- Binding Sites
- CCAAT-Enhancer-Binding Protein-alpha/genetics
- CCAAT-Enhancer-Binding Protein-alpha/metabolism
- CCAAT-Enhancer-Binding Protein-beta/genetics
- CCAAT-Enhancer-Binding Protein-beta/metabolism
- CCAAT-Enhancer-Binding Proteins/genetics
- CCAAT-Enhancer-Binding Proteins/metabolism
- Chromosomes, Human, Pair 14
- Chromosomes, Human, Pair 18
- Gene Expression Regulation, Neoplastic
- Homeodomain Proteins/metabolism
- Humans
- Lymphoma, Follicular/genetics
- Mutation
- Promoter Regions, Genetic
- Proto-Oncogene Proteins c-bcl-2/genetics
- Proto-Oncogene Proteins c-bcl-2/metabolism
- RNA, Small Interfering
- Response Elements
- Transfection
- Translocation, Genetic/genetics
- Tumor Cells, Cultured
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Affiliation(s)
- Caroline A Heckman
- Center for Molecular Biology in Medicine, Veterans Affairs Palo Alto Health Care System, Palo Alto, CA 94304, USA
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Wheeler MA, Yoon JH, Olsson LE, Weiss RM. Cyclooxygenase-2 protein and prostaglandin E(2) production are up-regulated in a rat bladder inflammation model. Eur J Pharmacol 2001; 417:239-48. [PMID: 11334856 DOI: 10.1016/s0014-2999(01)00911-6] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Cyclooxygenase-1 and cyclooxygenase-2 mRNAs and proteins and prostaglandin E(2) production are evaluated in a rat model of inflammation in which Escherichia coli lipopolysaccharide is intraperitoneally injected or intravesically instilled into the bladder. While cyclooxygenase-1 mRNA and protein and cyclooxygenase-2 mRNA do not change in bladders treated with lipopolysaccharide, cyclooxygenase-2 protein is elevated in bladders from rats intravesically instilled with lipopolysaccharide or phosphate buffered saline (PBS) or intraperitoneally injected with lipopolysaccharide. Urinary prostaglandin E(2) levels and prostaglandin E(2) synthesis in bladder particulates are elevated by intravesical instillation and intraperitoneal injection of lipopolysaccharide. The nitric oxide donor, S-nitroso-N-acetyl-D,L-penicillamine, increases prostaglandin E(2) synthesis in bladders from lipopolysaccharide intravesically instilled and intraperitoneally injected rats. Lipopolysaccharide increases prostaglandin E(2) synthesis by increasing cyclooxygenase-2 protein levels in rat bladder and prostaglandin E(2) synthesis may be further elevated by increases in nitric oxide caused by an up-regulation of inducible nitric oxide synthase (iNOS).
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Affiliation(s)
- M A Wheeler
- Section of Urology, Department of Surgery, Yale University School of Medicine, PO Box 208041, New Haven, CT 06520-8041, USA
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Abstract
This article reports a review of focal retrograde amnesia (FRA), or the phenomenon of organically based severe memory loss restricted to retrograde, or pretraumatic, memory. Cases of FRA are classified according to the type of memory loss: episodic, semantic, or both. A few different clusters of the disorder were identified. Lesions to either the anterior temporal lobes or the posterior/visual cortex can result in an FRA that devastates retrograde episodic memory, while having smaller effects on semantic memory. A number of left-hemisphere patients have FRA confined to semantic memory. There are several additional examples of FRA following minor cerebral trauma that disrupts either episodic memory alone or both episodic and semantic memory that are not accompanied by evidence of structural brain lesions. We discuss these different profiles of FRA and their implications for the understanding of memory retrieval.
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Affiliation(s)
- M A Wheeler
- Department of Psychology, Weiss Hall, Temple University, Philadelphia, PA 19122, USA.
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Abstract
CONTEXT Dysregulation of apoptosis may favor onset and progression of cancer and influence response to therapy. Survivin is an inhibitor of apoptosis that is selectively overexpressed in common human cancers, but not in normal tissues, and that correlates with aggressive disease and unfavorable outcomes. OBJECTIVE To investigate the potential suitability of survivin detection in urine as a novel predictive/prognostic molecular marker of bladder cancer. DESIGN, SETTING, AND PATIENTS Survey of urine specimens from 5 groups: healthy volunteers (n = 17) and patients with nonneoplastic urinary tract disease (n = 30), genitourinary cancer (n = 30), new-onset or recurrent bladder cancer (n = 46), or treated bladder cancer (n = 35), recruited from 2 New England urology clinics. MAIN OUTCOME MEASURES Detectable survivin levels, analyzed by a novel detection system and confirmed by Western blot and reverse transcriptase polymerase chain reaction (RT-PCR), in urine samples of the 5 participant groups. RESULTS Survivin was detected in the urine samples of all 46 patients with new or recurrent bladder cancer using a novel detection system (31 of 31) and RT-PCR (15 of 15) methods. Survivin was not detected in the urine samples of 32 of 35 patients treated for bladder cancer and having negative cystoscopy results. None of the healthy volunteers or patients with prostate, kidney, vaginal, or cervical cancer had detectable survivin in urine samples. Of the 30 patients with nonneoplastic urinary tract disease, survivin was detected in 3 patients who had bladder abnormalities noted using cystoscopy and in 1 patient with an increased prostate-specific antigen level. Patients with low-grade bladder cancer had significantly lower urine survivin levels than patients with carcinoma in situ (P =.002). CONCLUSIONS Highly sensitive and specific determination of urine survivin appears to provide a simple, noninvasive diagnostic test to identify patients with new or recurrent bladder cancer.
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Affiliation(s)
- S D Smith
- Yale University School of Medicine, BCMM436B, 295 Congress Ave, New Haven, CT 06536, USA
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Derweesh IH, Wheeler MA, Weiss RM. Alterations in G-proteins and beta-adrenergic responsive adenylyl cyclase in rat urinary bladder during aging. J Pharmacol Exp Ther 2000; 294:969-74. [PMID: 10945848] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/17/2023] Open
Abstract
Decreased response of bladder to beta-adrenergic stimulation with aging is related to decreased adenylyl cyclase activity and possibly to changes in guanine nucleotide regulatory protein (G-protein) content or function. G-protein content was quantified by Western blot analysis using antibodies to Gsalpha, Goalpha, and Gialpha in 21-day-old (weanling), 90-day-old (young adult), 6-month-old (adult), and 24-month-old (old) rat bladders. Gi/Go function in bladders with aging was measured by ADP-ribosylation with pertussis toxin. Content of Gsalpha, Goalpha, and Gialpha was lower in 90-day-old bladder than in 21-day-old bladder. Gsalpha content was similar in the 21-day-, 6-month-, and 24-month-old bladders. Gialpha content as well as pertussis toxin-catalyzed ADP-ribosylation was higher in 24-month-old bladders than in 21- and 90-day-old bladders. Pertussis toxin-catalyzed ADP-ribosylation of bladder membranes and treatment of bladder with protein kinase A inhibitors reversed the age-dependent decline in isoproterenol stimulation of adenylyl cyclase. Decreases in beta-adrenergic-induced relaxation response with age in rat bladder are due in part to increases in the content and functional activity of pertussis toxin-sensitive G-protein.
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Affiliation(s)
- I H Derweesh
- Section of Urology, Yale University School of Medicine, New Haven, CT 06520-8041, USA
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20
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Abstract
Although the anatomical and functional substrates subserving face recognition have been subject to extensive investigation, the underpinnings of self-face recognition are not well understood. Given the evidence that own-face recognition has been demonstrated by a select number of species, it is intriguing to speculate whether self-face recognition is accomplished via a 'self-network' or simply a 'face-network' within the brain. Furthermore, the relationship of self-recognition to other self-processes, such as self-evaluation and autobiographical retrieval, are not clearly defined. However, data from fMRI, ERPs and repetitive transcranial magnetic stimulation as well as from split-brain studies and patients with focal lesions, indicate that the prefrontal cortex, with possible right hemisphere lateralization, may be a preferential component in self-recognition. Studies using these methods, as well as PET, have indicated that the self-processes of self-evaluation and autobiographical memory preferentially engage networks within the right fronto-temporal region. Although it is highly improbable that there is a 'self-recognition' or 'self' center, it appears that there may be a bias for the processing of 'self' within the right prefrontal cortex.
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Affiliation(s)
- JP Keenan
- Laboratory for Magnetic Brain Stimulation Harvard Medical School, Department of Neurology, Beth Israel Deaconess Medical Center, 330 Brookline Ave, Boston, MA 02215, USA
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21
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Abstract
BACKGROUND Acute rejection and urinary tract infection (UTI) both increase nitric oxide synthase (NOS) activity in urine from renal transplant patients. Also, with rejection, a regulatory interplay between nitric oxide (NO) and cytokines has been suggested. Thus, measurement of the temporal changes of NOS products and cytokines in urine will provide a strategy for the diagnosis of acute rejection and for its differentiation from UTI. METHODS Soluble interleukins (ILs) and NOS-related products, cyclic GMP (cGMP), nitrate, and nitrite were measured in 192 urine samples consecutively collected from 13 patients within the first three months of transplantation. Sixty-seven additional urine specimens were collected randomly from 24 patients for follow-up analysis of the nitrate test. RESULTS Among patients who experienced rejection, the percentage (%) binding of IL-2 increased within the first five days (P = 0.0004) after transplantation and one to five days prior to the clinical diagnosis (dx) of rejection (P = 0.02). Tumor necrosis factor-alpha, IL-6, and IL-8 increased at the time of rejection dx (P < or = 0.01). With UTI, IL-2 (P = 0.01) decreased one to five days prior to dx, and IL-10 (P = 0.003) increased one to five days after dx. Although cGMP and nitrate are dependent variables, cGMP increased (P < or =0.0009) with both rejection and UTI, and nitrate increased (P = 0.0001) with rejection and decreased (P = 0.0001) with UTI. Prior to formal dx (1 to 5 days), urine nitrate clearly differentiated rejection (3004 to 7451 micromol/L) from UTI (90 to 885 micromol/L) and controls (1059 to 3235 micromol/L). The additional 67 urines demonstrated that the sensitivity of the nitrate test for rejection and UTI was 100%. CONCLUSIONS In renal transplant patients, specific temporal changes in urine cytokine levels do occur with acute rejection and UTI, but urine nitrate levels are the most precise at differentiating rejection from UTI.
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Affiliation(s)
- S D Smith
- Sections of Urology and Transplantation, Department of Surgery, Yale University School of Medicine, New Haven, CT 06520-8041, USA
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Wheeler MA, Taylor CM, Williams M, Moghal N. Factor V Leiden: a risk factor for renal vein thrombosis in renal transplantation. Pediatr Nephrol 2000; 14:525-6. [PMID: 10872199] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/16/2023]
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Swana HS, Smith SD, Perrotta PL, Saito N, Wheeler MA, Weiss RM. Inducible nitric oxide synthase with transitional cell carcinoma of the bladder. J Urol 1999; 161:630-4. [PMID: 9915473] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/10/2023]
Abstract
PURPOSE Nitric oxide (NO) plays a critical role as both a cell signaling molecule and as a cytotoxic/cytostatic mediator. Nitric oxide synthase (NOS) present in macrophages and neutrophils produces NO in response to immune stimulation. We evaluated NO production in both bladder tissue and urine from patients with transitional cell carcinoma (TCC) of the bladder. MATERIALS AND METHODS Inducible NOS (iNOS) RNA and protein were evaluated in bladder tissue from patients with and without TCC. Human iNOS-RNA products were identified with the reverse transcriptase-polymerase chain reaction (RT-PCR). Western blot analysis using a polyclonal antibody directed against iNOS recognized immunoreactive iNOS protein. Using the same iNOS antibody, the distribution of iNOS was examined in formalin-fixed, paraffin embedded samples of various grades of TCC. NOS activity was measured in the urine particulate fraction from patients with TCC and from controls by the conversion of [14C]-L-arginine to [14C]-L-citrulline. RESULTS Inducible NOS-RNA products and iNOS specific proteins were found in bladder tissue that contained TCC but not in control bladder tissue. Inducible NOS was uniformly localized in inflammatory cells within the carcinomas. Scattered tumor cells expressed iNOS in 8 of 12 specimens. There was no clear relationship between tumor immunoreactivity and tumor grade. NOS activity in urine from patients with TCC was not significantly elevated or decreased in comparison with control urine. CONCLUSIONS Inducible NOS is expressed by cells comprising and surrounding human bladder tumors. It is primarily localized to inflammatory cells, but also is demonstrated within individual tumor cells.
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Affiliation(s)
- H S Swana
- Department of Surgery, Yale University School of Medicine, New Haven, Connecticut 06520-8041, USA
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Korting GE, Smith SD, Wheeler MA, Weiss RM, Foster HE. A randomized double-blind trial of oral L-arginine for treatment of interstitial cystitis. J Urol 1999; 161:558-65. [PMID: 9915448] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/10/2023]
Abstract
PURPOSE Nitric oxide synthase activity is decreased in the urine of patients with interstitial cystitis compared to the urine of controls. In a preliminary trial oral L-arginine, the substrate for nitric oxide synthase, increased urinary nitric oxide synthase activity and improved interstitial cystitis symptoms. This randomized, double-blind, placebo controlled study further investigates the efficacy of L-arginine treatment for interstitial cystitis. MATERIALS AND METHODS A total of 53 interstitial cystitis patients were assigned to receive daily 1,500 mg. L-arginine or placebo orally for 3 months. Interstitial cystitis symptoms were assessed by interviews at 2 weeks, and 1, 2 and 3 months. RESULTS The trial was completed by 21 of 27 patients in the L-arginine group and 25 of 26 in the placebo group. Using per protocol analysis 29% (6 of 21 patients) in the L-arginine group and 8% (2 of 25) in the placebo group were clinically improved by the end of the trial (p = 0.07). A Likert scale showed greater global improvement in the L-arginine group (48%, 10 of 21) compared to the placebo group (24%, 6 of 25) at 3 months (p = 0.05) with a decrease in pain intensity (p = 0.04), and tendency toward improvement in urgency (p = 0.06) and frequency of pain (p = 0.09). Using an intention to treat approach to analysis there were no differences between groups. CONCLUSIONS Oral L-arginine (1,500 mg. daily) may decrease pain and urgency in a subset of interstitial cystitis patients.
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Affiliation(s)
- G E Korting
- Department of Surgery, Yale University School of Medicine, New Haven, Connecticut 06520-8041, USA
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Affiliation(s)
- M A Wheeler
- Section of Urology, Yale School of Medicine, New Haven, Connecticut 06520-9041, USA
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Abstract
BACKGROUND Nitroblue tetrazolium (NBT) reduction to formazan has been used as a marker for nitric oxide synthase (NOS). Since inducible NOS activity is elevated in urine from patients with urinary tract infections (UTIs), we investigated the accuracy of NBT reduction as an early predictor of UTIs and quantified the relationship between inducible NOS and NBT. METHODS Urine samples from 434 patients were screened for the presence of UTIs with leukocyte-esterase and nitrite dipsticks and with NBT reduction. The rapid screening results from each test were compared to urine culture results. In addition, NBT reduction parameters were measured in urine pellet at 595 nm after incubation with one of four factors: NOS cofactors, NOS inhibitors, NADH, or superoxide dismutase/catalase. RESULTS As a urine screening test for UTIs, NBT reduction was more sensitive with a higher negative predictive accuracy than the nitrite dipstick. NBT reduction also was more specific with a higher positive predictive accuracy and negative predictive accuracy than the leukocyte-esterase dipstick. In infected urine pellet, both NADPH, a NOS cofactor, and NADH increased NBT reduction. Superoxide dismutase/catalase decreased NBT reduction. CONCLUSIONS Although NOS may not be the only NBT reducing enzyme, rapid, visible reduction of NBT is induced in urine from patients with UTIs.
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Affiliation(s)
- S D Smith
- Department of Surgery, Yale University School of Medicine, New Haven, Connecticut 06520-8041, USA
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Olsson LE, Wheeler MA, Sessa WC, Weiss RM. Bladder instillation and intraperitoneal injection of Escherichia coli lipopolysaccharide up-regulate cytokines and iNOS in rat urinary bladder. J Pharmacol Exp Ther 1998; 284:1203-8. [PMID: 9495884] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Systemic bacterial lipopolysaccharides (LPS) induce inflammatory responses characteristic of sepsis. Instillation of LPS into rat bladder produces a localized inflammatory response similar to that seen in urinary tract infections (UTIs). Four hours after intravesical instillation of LPS, neutrophils infiltrate into the bladder, and mRNA for inducible nitric oxide synthase (iNOS) and the cytokines, interleukin (IL)-6 and IL-10, is detected in rat bladder but not in the kidney. Induction of iNOS protein is inferred because urinary nitrate and cGMP levels are increased 4 hr after LPS intravesical instillation and remain elevated for at least 24 hr. When LPS is injected intraperitoneally, iNOS and IL-6 mRNA are induced both in the bladder and in the kidney. These data are consistent with the effects of intravesical instillation of LPS remaining localized, iNOS activity increases in both particulate and soluble bladder fractions when measured 4 hr after intravesical instillation of LPS. The magnitude of these increases in iNOS activity in the bladder is not as great as when LPS is injected intraperitoneally. Intravesical instillation of LPS induces no increase in lung or kidney NOS activity. The localized inflammatory response produced by intravesical instillation of LPS demonstrates the importance of LPS as a mediator of the host response in UTIs and supports the use of urinary measurements of nitrate and cGMP in humans as indicative of the localized induction of iNOS in UTIs.
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Affiliation(s)
- L E Olsson
- Section of Urology, Yale University School of Medicine, New Haven, Connecticut, USA
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Wheeler MA, Smith SD, Saito N, Foster HE, Weiss RM. Effect of long-term oral L-arginine on the nitric oxide synthase pathway in the urine from patients with interstitial cystitis. J Urol 1997; 158:2045-50. [PMID: 9366309 DOI: 10.1016/s0022-5347(01)68150-3] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
PURPOSE We attempted to determine whether oral L-arginine, the substrate for nitric oxide synthase, increases nitric oxide synthase activity and cyclic guanosine monophosphate (cGMP) levels in the urine from interstitial cystitis patients. Nitric oxide and cGMP are decreased in urine from interstitial cystitis patients and both induce smooth muscle relaxation and immunological responses. Increasing urinary nitric oxide and cGMP may ameliorate interstitial cystitis symptoms. MATERIALS AND METHODS Eight patients with interstitial cystitis were given L-arginine (1,500 mg. a day) orally for 6 months. Before and during treatment nitric oxide synthase activity and inducible nitric oxide synthase protein, cGMP, nitrate plus nitrite and interleukin 8 (IL-8) levels were measured in urine. RESULTS After 2 weeks to 1 month of oral L-arginine treatment, urinary levels of nitric oxide synthase related enzymes and products increased significantly, while levels of the cytokine IL-8 were not changed significantly. IL-8 was significantly elevated in interstitial cystitis patients with leukocyte esterase positive urine. CONCLUSIONS Long-term oral administration of L-arginine increases nitric oxide related enzymes and metabolites in the urine of patients with interstitial cystitis, which is associated with a decrease in interstitial cystitis related symptoms.
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Affiliation(s)
- M A Wheeler
- Department of Surgery, Yale University School of Medicine, New Haven, Connecticut, USA
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Abstract
PURPOSE Urinary nitric oxide synthase activity is decreased in patients with interstitial cystitis. Since nitric oxide may be an important determinant of the symptoms and immunological responses associated with interstitial cystitis, patients with this disease were treated with oral L-arginine, the substrate for nitric oxide synthase. MATERIALS AND METHODS Ten patients took 1.5 gm. L-arginine orally daily for 6 months. Interstitial cystitis symptoms were surveyed before and during the 6-month trial. RESULTS Oral L-arginine treatment resulted in a significant decrease in urinary voiding discomfort, lower abdominal pain and vaginal/urethral pain. Urinary frequency during the day and night also significantly decreased. CONCLUSIONS This self-controlled study provides evidence that long-term oral L-arginine improves interstitial cystitis related symptoms.
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Affiliation(s)
- S D Smith
- Department of Surgery, Yale University, School of Medicine, New Haven, Connecticut, USA
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Abstract
Adult humans are capable of remembering prior events by mentally traveling back in time to re-experience those events. In this review, the authors discuss this and other related capabilities, considering evidence from such diverse sources as brain imaging, neuropsychological experiments, clinical observations, and developmental psychology. The evidence supports a preliminary theory of episodic remembering, which holds that the prefrontal cortex plays a critical, supervisory role in empowering healthy adults with autonoetic consciousness-the capacity to mentally represent and become aware of subjective experiences in the past, present, and future. When a rememberer mentally travels back in subjective time to re-experience his or her personal past, the result is an act of retrieval from episodic memory.
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Affiliation(s)
- M A Wheeler
- Rotman Research Institute of Baycrest Centre, Toronto, Ontario, Canada.
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Wheeler MA, Pontari M, Dokita S, Nishimoto T, Cho YH, Hong KW, Weiss RM. Age-dependent changes in particulate and soluble guanylyl cyclase activities in urinary tract smooth muscle. Mol Cell Biochem 1997; 169:115-24. [PMID: 9089638 DOI: 10.1023/a:1006823611864] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Regional and age specific differences are observed in the sodium nitroprusside induced relaxation responses in the urinary tract. To clarify these differences, guanylyl cyclase activity is assayed in particulate and soluble fractions from the ureter, bladder dome, and urethra of young (11-18 days), adult (90-100 days), and old adult (2-3 years) guinea pigs. The rank order of soluble guanylyl cyclase activities is urethra = ureter > bladder dome with the largest decreases with aging occurring in the bladder. Atrial natriuretic factor (10(7) M) increases particulate guanylyl cyclase activity in the three tissues at all ages tested, with the activity being highest in the ureter. ATP (0.5 mM) activates particulate guanylyl cyclase in the ureter, bladder and urethra of old adult guinea pigs, and enhances atrial natriuretic factor induced activation of particulate guanylyl cyclase in all tissues and at all ages tested. The higher levels of soluble guanylyl cyclase activity in the urethra and ureter compared to the bladder parallel sodium nitroprusside induced relaxation in these tissues.
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Affiliation(s)
- M A Wheeler
- Section of Urology, Yale University School of Medicine, New Haven, CT 06520-8041, USA
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Martin TV, Wheeler MA, Weiss RM. Neurokinin induced inositol phosphate production in guinea pig bladder. J Urol 1997; 157:1098-102. [PMID: 9072551] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
PURPOSE To examine second messenger pathways involved in neurokinin induced bladder contractions. MATERIALS AND METHODS Neurokinin induced changes in inositol phosphate production and in adenylyl cyclase activity are measured in the guinea pig bladder. RESULTS Substance P, substance P methyl ester, neurokinin A, and neurokinin B each increase [3H]-inositol phosphate production in the guinea pig bladder. Substance P (10(-6) M) increases [3H]-inositol trisphosphate levels within 30 sec. Substance P and neurokinin A have an additive effect on inositol phosphate production, however substance P (10(-5) M) or neurokinin A (10(-5) M) induced inositol phosphate production is less than that induced by carbachol (10(-5) M). Neurokinin B and to a lesser extent neurokinin A inhibit forskolin-activated adenylyl cyclase activity. CONCLUSIONS These data are compatible with neurokinin-induced inositol phosphate production being coupled to increases in contractile force of the guinea pig urinary bladder, however more than one second messenger pathway may be involved.
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Affiliation(s)
- T V Martin
- Section of Urology, Yale University School of Medicine, New Haven, Connecticut, USA
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Wheeler MA, Smith SD, García-Cardeña G, Nathan CF, Weiss RM, Sessa WC. Bacterial infection induces nitric oxide synthase in human neutrophils. J Clin Invest 1997; 99:110-6. [PMID: 9011564 PMCID: PMC507774 DOI: 10.1172/jci119121] [Citation(s) in RCA: 220] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023] Open
Abstract
The identification of human inflammatory cells that express inducible nitric oxide synthase and the clarification of the role of inducible nitric oxide synthase in human infectious or inflammatory processes have been elusive. In neutrophil-enriched fractions from urine, we demonstrate a 43-fold increase in nitric oxide synthase activity in patients with urinary tract infections compared with that in neutrophil-enriched fractions from noninfected controls. Partially purified inducible nitric oxide synthase is primarily membrane associated, calcium independent, and inhibited by arginine analogues with a rank order consistent with that of purified human inducible nitric oxide synthase. Molecular, biochemical, and immunocytochemical evidence unequivocally identifies inducible nitric oxide synthase as the major nitric oxide synthase isoform found in neutrophils isolated from urine during urinary tract infections. Elevated inducible nitric oxide synthase activity and elevated nitric oxide synthase protein measured in patients with urinary tract infections and treated with antibiotics does not decrease until 6-10 d of antibiotic treatment. The extended elevation of neutrophil inducible nitric oxide synthase during urinary tract infections may have both antimicrobial and proinflammatory functions.
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Affiliation(s)
- M A Wheeler
- Department of Surgery, Yale University School of Medicine, New Haven, Connecticut 06520, USA
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Smith SD, Wheeler MA, Zhang R, Weiss ED, Lorber MI, Sessa WC, Weiss RM. Nitric oxide synthase induction with renal transplant rejection or infection. Kidney Int 1996; 50:2088-93. [PMID: 8943494 DOI: 10.1038/ki.1996.533] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
Nitric oxide (NO) is readily oxidized to nitrate and nitrite and NO activates guanylyl cyclase, increasing cyclic GMP levels. To determine if nitric oxide synthase (NOS) is present in urine collected daily from patients following renal transplantation, we evaluated NOS activity in the leukocyte-rich particulate fraction and measured nitrate, nitrite, and cyclic GMP levels in the supernatant fraction of the urine. Reverse transcriptase-PCR and cDNA sequencing confirmed the presence of inducible NOS (iNOS) in cells obtained from the urine of renal transplant patients with rejection. NOS activity was elevated significantly in renal transplant patients with rejection (6.40 +/- 1.47 pmol citrulline/min/mg protein) or with urinary tract infection (29.56 +/- 11.00 pmol citrulline/min/mg protein), when compared to post-renal transplantation patients without rejection or urinary tract infection (0.51 +/- 0.21 pmol citrulline/min/mg protein). Nitrate levels increased in renal transplant patients with rejection and nitrite levels increased in renal transplant patients with urinary tract infection (UTI). Cyclic GMP levels increased with both rejection and UTI. This study demonstrates the presence of NOS activity and inducible NOS-mRNA in cells isolated from the urine of patients undergoing renal allograft rejection.
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Affiliation(s)
- S D Smith
- Department of Surgery, Yale University, School of Medicine, New Haven, Connecticut, USA
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Smith SD, Wheeler MA, Foster HE, Weiss RM. Urinary nitric oxide synthase activity and cyclic GMP levels are decreased with interstitial cystitis and increased with urinary tract infections. J Urol 1996; 155:1432-5. [PMID: 8632605] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
PURPOSE Since urinary nitric oxide synthase (NOS) activity correlates with certain disease process affecting the urinary tract and since nitric oxide increases cyclic GMP levels by activating guanylyl cyclase, urinary particulate NOS activity and cyclic GMP levels are evaluated in female patients with interstitial cystitis (IC) and compared with those from female controls and female patients with urinary tract infections (UTIs). MATERIALS AND METHODS Urinary NOS activity is measured as the formation of [(14)C]-L-citrulline from [(14)C]-L-arginine, and urinary cyclic GMP levels are measured by an [(125)I]-radioimmunoassay. RESULTS Female patients with IC have significantly less NOS activity in their urine pellet particulate fractions than female control females UTIs, 2.3 +/- 1.0, 14 +/- 3.0, and 120 +/- 10 pmol. citrulline formed/min./mg. protein. Urinary cyclic GMP levels are significantly lower in IC patients than in female controls or females with UTIs: 0.50 +/- 0.06, 0.82 +/- 0.14. and 3.72 +/- 0.81 micromol. cyclic GMP/g. creatinine. CONCLUSIONS Regulation of urinary NOS activity with subsequent changes in nitric oxide and cyclic GMP may be an important determinant of symptoms and immunologic responses to UTIs and IC.
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Affiliation(s)
- S D Smith
- Section of Urology, Yale University, School of Medicine, New Haven, Connecticut, USA
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Mimata H, Wheeler MA, Fukumoto Y, Takigawa H, Nishimoto T, Weiss RM, Latifpour J. Enhancement of muscarinic receptor-coupled phosphatidyl inositol hydrolysis in diabetic bladder. Mol Cell Biochem 1995; 152:71-6. [PMID: 8609914 DOI: 10.1007/bf01076465] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
We previously have shown an increase in muscarinic receptor density in streptozotocin (STZ)-induced diabetic and sucrose-fed diuretic rat detrusor that correlates with an increase in the contractile response to muscarinic agonist (J Pharmacol Exp Ther 248:81, 1989; Diabetes 40: 265, 1991). To investigate the signal transduction pathway involved in this altered functional response, we examined muscarinic receptor-coupled phosphatidylinositol metabolism in STZ-diabetic, sucrose-fed diuretic and age-matched control rat bladders. [3H]myo-inositol uptake was similar in all groups, but incorporation of myo-inositol into phosphatidylinositol (PI) was significantly increased in the diabetic bladder compared to the sucrose-fed and control rat bladders. Carbachol-induced increase in inositol phosphate (IPs) production was higher in the diabetic bladder than in bladders from control and sucrose-fed animals although the EC50 values were similar for all groups. Enhanced inositol phosphate production after muscarinic agonist stimulation may be due not only to the upregulation of muscarinic receptors but also the increased incorporation of myo-inositol into PI in the STZ-induced diabetic bladder.
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Affiliation(s)
- H Mimata
- Section of Urology, Yale University School of Medicine, New Haven, CT 06510, USA
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Abstract
This article reports the outcome of a meta-analysis of the relation between the frontal lobes and memory as measured by tests of recognition, cued recall, and free recall. We reviewed experiments in which patients with documented, circumscribed frontal pathology were compared with normal control subjects on these three types of tests. Contrary to conventional wisdom, there is strong evidence that frontal damage disrupts performance on all three types of tests, with the greatest impairment in free recall, and the smallest in recognition.
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Affiliation(s)
- M A Wheeler
- Rotman Research Institute of Baycrest Centre, Toronto, Ontario, Canada
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Wheeler MA, Martin TV, Weiss RM. Effect of carbachol and norepinephrine on phosphatidyl inositol hydrolysis and cyclic AMP levels in guinea pig urinary tract. J Urol 1995; 153:2044-9. [PMID: 7752391] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
Muscarinic cholinergic and adrenergic agonist-induced changes in [3H]-phosphatidyl inositol (PI) hydrolysis and cyclic AMP (cAMP) levels were measured in guinea pig ureter, urethra and bladder dome. In the ureter, carbachol, norepinephrine and phenylephrine rapidly increased PI hydrolysis and basal cAMP levels, but did not decrease forskolin-stimulated cAMP levels. In the bladder dome, norepinephrine and phenylephrine produced a rapid but transitory increase in PI hydrolysis, but did not affect forskolin-stimulated cAMP levels. Carbachol produced a rapid and sustained increase in PI hydrolysis and also, at high concentrations, decreased forskolin-stimulated cAMP levels. In the urethra, norepinephrine and carbachol rapidly decreased forskolin-stimulated cAMP levels and later increased PI hydrolysis. Our data suggest that the predominant second messenger system in the ureter, dome, or urethra is more dependent on the tissue than on the agonist. These tissue-specific, agonist-induced rapid changes in second messenger levels may help coordinate the contraction-relaxation phenomena necessary for urinary tract function.
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Affiliation(s)
- M A Wheeler
- Section of Urology, Yale University School of Medicine, New Haven, Connecticut 06520-8041, USA
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Nishimoto T, Latifpour J, Wheeler MA, Yoshida M, Weiss RM. Age-dependent alterations in beta-adrenergic responsiveness of rat detrusor smooth muscle. J Urol 1995. [PMID: 7715014 DOI: 10.1016/s0022-5347(01)67508-6] [Citation(s) in RCA: 40] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
The relaxant effects of norepinephrine (NE, 10(-7) to 10(-4) M.) and isoproterenol (ISO, 10(-9) to 10(-4) M.) on maximal KCl-induced tonic contractions and the relaxant effects of ISO on contractions induced by electrical field stimulation (EFS) were measured in detrusor muscle strips obtained from 22-25 day, 90-95 day and 22-month-old male Fischer 344 rats. The maximum relaxant response to NE and ISO on KCl-induced tonic contractions decreased significantly with increasing age. The ED50 values for ISO, but not NE, increased with age. The maximum relaxant response to ISO on EFS-induced contractions also was reduced significantly in the old bladders. The relaxation effects of forskolin (10(-6) to 3 x 10(-5) M.), dibutyryl cyclic AMP (DBcAMP, 10(-4) to 3 x 10(-3) M.) and cholera toxin (10 micrograms/ml.) were examined on maximal KCl-induced contractions of the muscle strips obtained from the three age groups. The relaxant responses to forskolin decreased significantly with increasing age, whereas DBcAMP relaxed the muscle strips from the three age groups equally. Cholera toxin (10 micrograms) attenuated KCl-induced phasic contractions, and this effect was impaired in the aged rat detrusor. The density of beta-adrenergic receptors, as determined by radioligand binding with [125I]iodopindolol ([125I]-PIN) decreased with increasing age. These data demonstrate an age-related decrease in the responsiveness of the bladder detrusor to beta-adrenergic stimulation that may be related to the decreased density of beta-adrenergic receptors and decreased cyclic AMP (cAMP) production.
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Affiliation(s)
- T Nishimoto
- Section of Urology, Yale University School of Medicine, New Haven, Connecticut 06510, USA
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40
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Abstract
Soluble and particulate fractions from rabbit urethra converted [14C]arginine to [14C]citrulline, indicating the presence of nitric oxide synthase activity in these fractions. Both soluble and particulate nitric oxide synthase activities were NADPH dependent, and the soluble activity was Ca2+ dependent. Three nitric oxide synthase (NOS) inhibitors affected transmural nerve stimulation induced relaxation responses in the rabbit urethra and the activity of soluble nitric oxide synthase with the same rank order of potency, i.e., NG-nitro-L-arginine (NNA) > NG-methyl-L-arginine (NMA) > canavanine (CAN). The rank order of potency with respect to particulate NOS activity was CAN > NMA = NNA. The relaxation responses to electrical stimulation were accompanied by increases in cyclic GMP. These results suggest that NOS activity found in the soluble fraction of urethral homogenates produces nitric oxide that in turn increases cyclic GMP levels which mediates the relaxation responses induced by transmural nerve stimulation in the rabbit urethra.
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Affiliation(s)
- S Dokita
- Section of Urology, Yale University School of Medicine, New Haven, CT 06510
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Abstract
To further define the endogenous sources of urine nitrite in urinary tract infections, we measured urinary nitrite levels by the Griess method and assayed urinary nitric oxide (NO) synthase activity by the conversion of 14C-arginine to 14C-citrulline. Endogenous production of 14C-citrulline was confirmed by thin layer chromatography. Exogenous L-arginine increased nitrite production in whole infected urine, but not in bacteria isolated from infected urine. Urinary tract infections significantly increased NO synthase activity in soluble urine fractions, although soluble activity was less than 10% of particulate activity. Urine particulate fractions from women with non-infected urine had greater NO synthase activity than particulate fractions from men with non-infected urine, 11 +/- 2 and 0.2 +/- 0.1 picomol/min/mg protein, respectively. Urinary tract infections increased NO synthase activity in urine particulate fractions from women and men, 99 +/- 20 and 48 +/- 9 picomol/min/mg protein, respectively. The conversion of 14C-arginine to 14C-citrulline required NADPH, was calcium independent, and was inhibited to a greater extent by L-canavanine than by NG-monomethyl-L-arginine or NG-nitro-L-arginine. Human infected urine contains an isoform of NO synthase which is an endogenous source of urine nitrite.
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Affiliation(s)
- S D Smith
- Section of Urology, Yale University School of Medicine, New Haven, Connecticut
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42
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Dokita S, Morgan WR, Wheeler MA, Yoshida M, Latifpour J, Weiss RM. NG-nitro-L-arginine inhibits non-adrenergic, non-cholinergic relaxation in rabbit urethral smooth muscle. Life Sci 1991; 48:2429-36. [PMID: 1675415 DOI: 10.1016/0024-3205(91)90377-n] [Citation(s) in RCA: 85] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Electrical field stimulation induced a relaxation response in female rabbit urethral smooth muscle strips precontracted with phenylephrine. The relaxation response was inhibited by tetrodotoxin, but not by atropine, propranolol, or hexamethonium. The relaxation response thus results from stimulation of inhibitory non-adrenergic, non-cholinergic nerves. The electrically induced relaxation response was inhibited by an inhibitor of nitric oxide biosynthesis, NG-nitro-L-arginine. This inhibition was overcome by addition of a precursor of nitric oxide, L-arginine. An inhibitor of soluble guanylate cyclase, methylene blue, reduced the relaxation response, and a selective cyclic GMP phosphodiesterase inhibitor, M & B 22948, potentiated the relaxation response. These data indicate that agents which affect the biosynthesis of nitric oxide are associated with the urethral relaxation response evoked by electrical field stimulation, and that cyclic GMP may mediate the relaxation response.
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Affiliation(s)
- S Dokita
- Section of Urology, Yale University School of Medicine, New Haven, Connecticut 06510
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43
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Wheeler MA, Pontari M, Nishimoto T, Weiss RM. Changes in lipid composition and isoproterenol- and ethanol-stimulated adenylate cyclase activity in aging Fischer rat bladders. J Pharmacol Exp Ther 1990; 254:277-83. [PMID: 2366184] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
In the aging rat bladder dome, changes are noted in membrane composition and in the activity of the membrane-bound enzyme, adenylate cyclase (AC). When bladder domes from 22 day and 22 to 24 month Fischer rats are compared, changes in composition include: a 25% decrease in percentage of protein [(milligrams of protein per milligram of wet weight) x 100]; an approximately 40% decrease in both the total phospholipid content and in the content of the major phospholipids, phosphatidylcholine and phosphatidylethanolamine; and a 69% increase in the cholesterol to phospholipid ratio. These changes are indicative of a more rigid lipid bilayer in the aged rat bladder. Changes in AC with aging include a decrease in basal and forskolin-activated AC and a loss of the ability of isoproterenol to activate AC in the aged (22-24 month) rat bladder dome homogenate. Activation by isoproterenol (ISO; 3 microM) is 55 and 72% over 5' guanylimidodiphosphate [Gpp(NH)p; 1 microM] controls in 22 day and 90 day rat bladder dome homogenates, respectively. Activation by AC by NaF and Gpp(NH)p does not decline with aging. Ethanol, an agent that increases membrane fluidity, stimulates AC to a much greater extent in homogenates from the 22 month than from the 22 day or 90 day rat bladder dome. The ethanol-induced activation occurs not only in basal AC but also in Gpp(NH)p- and ISO-plus Gpp(NH)p-activated AC. The observed changes in AC with aging in part may reflect changes in the membrane lipid environment.
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Affiliation(s)
- M A Wheeler
- Yale University School of Medicine, Department of Surgery/Urology, New Haven, Connecticut
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44
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Weiss RM, Wheeler MA. Insulin activation of cyclic AMP phosphodiesterase in intact ureteral segments. J Pharmacol Exp Ther 1988; 247:630-4. [PMID: 2846825] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023] Open
Abstract
Low doses of insulin (0.1-50 nM) when presented to intact ureteral segments increase cyclic AMP (cAMP) phosphodiesterase (PDE) activity in subsequently isolated supernatant and particulate fractions. The stimulation of cAMP PDE occurs within 5 to 10 min of the introduction of insulin. When cyclic GMP or high concentrations of cAMP (greater than 5 microM) are used as substrate, insulin does not increase PDE activity. Although the insulin-increased cAMP PDE exhibits the same sensitivity as control PDE from untreated preparations to isobutylmethyl xanthine, a nonspecific PDE inhibitor, and M & B 22,948, a relatively selective cyclic GMP PDE inhibitor, differences in the degree of inhibition of PDE activity are seen in the insulin-treated and untreated preparations with the low Km cAMP PDE inhibitors Ro20-1724, rolipram, amrinone and milrinone and with cyclic GMP. Pertussis toxin, which modifies GTP regulatory proteins of the adenylate cyclase enzyme and the photoreceptor PDE, blocks cAMP PDE activation by insulin.
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Affiliation(s)
- R M Weiss
- Yale University School of Medicine, Department of Surgery/Urology, New Haven, Connecticut
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45
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Abstract
Cyclic AMP and cyclic GMP phosphodiesterase (PDE) activities and calmodulin levels were determined in ureters from guinea pigs of the following ages: 50 and 56 days fetuses, three, 10, 21, 50, and 90 days, and three years old. While there is little change in ureteral cyclic AMP-PDE with age, cyclic GMP-PDE increases with age. Activity of cyclic GMP-PDE in supernatants prepared from three-year-old guinea pig ureter homogenates is 462% and 216% higher than that from 50-day fetus and three-day animals, respectively. Calmodulin levels have a bimodal distribution with age; values are highest in supernatants from 10 and 21 day ureters, but also increase in the three-year ureters when compared to 50 and 90-day values.
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Affiliation(s)
- Y H Cho
- Section of Urology, Yale University School of Medicine, New Haven, Connecticut 06504
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46
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Morita T, Latifpour J, O'Hollaren B, Wheeler MA, Weiss RM. Sex differences in function and distribution of alpha 1- and alpha 2-adrenoceptors in rabbit urethra. Am J Physiol 1987; 252:F1124-8. [PMID: 3035945 DOI: 10.1152/ajprenal.1987.252.6.f1124] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
To define the functional role of postsynaptic alpha-adrenoceptors in urethral smooth muscle, we examined the effects of various alpha-adrenergic agonists and antagonists on the contractile properties of the isolated urethra of male and female rabbits and quantified the population of alpha 1-and alpha 2-adrenoceptors, using radioligand receptor binding techniques. Norepinephrine (NE), epinephrine, and phenylephrine, an alpha 1-adrenergic agonist, induced increases in contractile force in both the male and female urethra. Clonidine, an alpha 2-adrenergic agonist, caused a relatively large contractile response in the female urethra but only a small contractile response in the male urethra. Receptor binding studies indicated that the male urethra contains almost equal amounts of alpha 1- and alpha 2-adrenoceptors (32 vs. 34 fmol/mg, respectively), whereas the female urethra contains a significantly greater density of alpha 2- than alpha 1-adrenoceptors (122 vs. 34 fmol/mg, respectively). Our studies indicate that both alpha 1- and alpha 2-adrenoceptors cause contractile responses in male and female rabbit urethra; and the greater response to alpha 2-agonist in female than male urethra is correlated with a higher density of alpha 2-adrenoceptors in this tissue.
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47
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Abstract
Contractile responses of urinary bladder muscle strips to prostaglandin (PG) E1, E2 and F2 alpha were compared in young and old rabbits. All PGs tested caused an increase in contractile force of urinary bladder muscle strips from young (3 weeks) and old (greater than 2 years) rabbits. The contractile response was most marked with PGE2 at concentrations of 10(-10)-10(-7) M in muscle strips from both young and old rabbits. At a high concentration (10(-5) M), the contractile response was most marked with PGF2 alpha in young rabbit bladder muscle strips, whereas in old rabbit bladder muscle strips the magnitude of the responses to PGE2 and PGF2 alpha were equal at 10(-6) M and both were greater than the response to PGE1. The contractile response to PGE1 was greater in old detrusor than in young detrusor at concentrations greater than or equal to 10(-6) M, whereas the contractile response to PGE2 (10(-7)-10(-5) M) and PGF2 alpha (10(-6)-10(-5) M) were greater in young detrusor than in old detrusor. These data show that rabbit detrusor muscle shows a contractile response to PGE1, E2 and F2 alpha and that the magnitude of these responses vary with age.
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48
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Wheeler MA, Housman A, Cho YH, Weiss RM. Age dependence of adenylate cyclase in guinea pig ureter homogenate. J Pharmacol Exp Ther 1986; 239:99-103. [PMID: 3761201] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023] Open
Abstract
Adenylate cyclase activity was measured in ureteral homogenates from guinea pigs of five age groups, ranging from neonates to older adults (retired breeders). Isoproterenol stimulation of adenylate cyclase activity is lost completely in ureters from 90 day and older animals. Forskolin activation also declines rapidly with increasing age; there is a significant (39%) decrease in activation at 30 days when compared to 10-day values with a further decline at 90 days. At 90 days, NaF, GTP and 5'-guanylimido-diphosphate stimulation of adenylate cyclase decreases by only 1, 9 and 23%, respectively, from the 10-day values. Prostaglandin E1 stimulation over 5'-guanylimido-diphosphate control does not decrease with age. 5'-Guanylimido-diphosphate in the presence of ethanol, activates adenylate cyclase to a greater extent in the older animals. These data may suggest that the decreased ability to activate adenylate cyclase with age may be due to a loss of the efficiency of coupling in the more rigid aged membranes. Other explanations include loss of catalytic function with age. The loss of adenylate cyclase activity in aging correlates well with our previously reported study showing that isoproterenol causes a greater decrease in contractility of ureters from younger than from older guinea pigs.
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49
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Morita T, Wheeler MA, Miyagawa I, Kondo S, Weiss RM. Effects of forskolin on contractility and cyclic AMP levels in rabbit detrusor muscle. TOHOKU J EXP MED 1986; 149:283-5. [PMID: 2429401 DOI: 10.1620/tjem.149.283] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Forskolin caused a concentration-dependent relaxation and increase in cyclic AMP levels in rabbit detrusor muscle. Propranolol, a beta-adrenoceptor antagonist, did not affect the relaxation induced by forskolin. 3-isobutyl-1-metylxanthine (IBMX), a cyclic nucleotide phosphodiesterase inhibitor, potentiated the relaxation induced by forskolin. These data suggest that the relaxation of rabbit detrusor muscle induced by forskolin is mediated by cyclic AMP accumulation resulting from activation of adenylate cyclase.
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50
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Abstract
Resistance to fluid flow in the canine ureter can be divided into two categories. The higher resistance is recorded at flow rates less than or equal to 2.16 ml./min. At these rates the ureter is able to completely coapt its walls so that urine is transported in individual boluses. The lower resistance is recorded at flow rates greater than or equal to 5.40 ml./min. At these rates the ureteral walls remained open and urine is transported as a column of fluid. Noradrenaline causes a marked increase in ureteral resistance at low flow rates and a small but statistically significant increase in ureteral resistance at high flow rates. Acetylcholine increases resistance only at the low flow rates. Isoproterenol significantly decreases resistance at both low and high flow rates. These findings are consistent with ureteral resistance to fluid flow being composed of two components. One is the ureteral peristaltic contraction which plays a principal role in urinary bolus transport at low flows; the other is ureteral wall tonus, which plays an important role in the transport of columns of urine by the ureter, which does not coapt its walls, at the higher flow rates.
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