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Wu S, Yin Y, Du L. The bidirectional relationship of depression and disturbances in B cell homeostasis: Double trouble. Prog Neuropsychopharmacol Biol Psychiatry 2024; 132:110993. [PMID: 38490433 DOI: 10.1016/j.pnpbp.2024.110993] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/09/2023] [Revised: 03/08/2024] [Accepted: 03/12/2024] [Indexed: 03/17/2024]
Abstract
Major depressive disorder (MDD) is a recurrent, persistent, and debilitating neuropsychiatric syndrome with an increasing morbidity and mortality, representing the leading cause of disability worldwide. The dysregulation of immune systems (including innate and adaptive immune systems) has been identified as one of the key contributing factors in the progression of MDD. As the main force of the humoral immunity, B cells have an essential role in the defense against infections, antitumor immunity and autoimmune diseases. Several recent studies have suggested an intriguing connection between disturbances in B cell homeostasis and the pathogenesis of MDD, however, the B-cell-dependent mechanism of MDD remains largely unexplored compared to other immune cells. In this review, we provide an overview of how B cell abnormality regulates the progression of MMD and the potential consequence of the disruption of B cell homeostasis in patients with MDD. Abnormalities of B-cell homeostasis not only promote susceptibility to MDD, but also lead to an increased risk of developing infection, malignancy and autoimmune diseases in patients with MDD. A better understanding of the contribution of B cells underlying MDD would provide opportunities for identification of more targeted treatment approaches and might provide an overall therapeutic benefit to improve the long-term outcomes of patients with MDD.
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Affiliation(s)
- Shusheng Wu
- Department of Neurology, Affiliated Hospital of Yangzhou University, Jiangsu, China
| | - Yuye Yin
- College of Bioscience and Biotechnology, Yangzhou University, Yangzhou, Jiangsu, China
| | - Longfei Du
- Department of Laboratory Medicine, Affiliated Hospital of Yangzhou University, Yangzhou, Jiangsu, China.
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Depressive symptoms predict antibody titers after a second dose of the SARS-CoV-2 BNT162b2 vaccine among hospital workers in Japan. Brain Behav Immun 2023; 107:414-418. [PMID: 36116693 PMCID: PMC9476373 DOI: 10.1016/j.bbi.2022.09.004] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/17/2022] [Revised: 08/11/2022] [Accepted: 09/11/2022] [Indexed: 12/13/2022] Open
Abstract
BACKGROUND Although factors associated with the antibody response to the BNT162b2 mRNA COVID-19 vaccine have been reported, psychological factors have not been examined. Depression or anxiety may affect vaccine reactions because these factors influence immune responses. This study aimed to determine whether psychological status at the time of vaccination predicts antibody responses. METHODS A prospective observational study of the BNT162b2 mRNA COVID-19 vaccine response was carried out among individuals attending for an annual health check-up. Participants included 78 volunteers out of 80 hospital workers in Nagoya, Japan. No participants had been infected with COVID-19 and all gave written informed consent to participate in the study. Blood samples were obtained approximately 28 days after the second dose of the vaccine, and antibody titers of the SARS-CoV-2 spike protein were determined using the SARS-CoV-2 IgG II Quant assay. Participants completed the Japanese version of the hospital anxiety and depression scale (HADS) questionnaire, one day before both vaccinations. Participants also recorded any adverse reactions, such as body temperature and other side effects, every day for two weeks after each dose. The relationships between antibody titers and the predictive factors were analyzed using multiple linear regression analysis, with the antibody titers as the dependent variables, followed by univariate analysis. RESULTS Multiple linear regression analysis revealed that no or excessive alcohol intake (p = 0.039), poor results from a health check-up (p = 0.011), a longer duration between the second dose and blood collection (p = 0.039), and increased degree of depressive symptoms (p = 0.041) were significant negative predictors of antibody titers, while body temperature one day after the second dose as a significant positive predictor of antibody titers (p < 0.0005). CONCLUSION We identified that depressive symptoms just before the second dose of the BNT162b2 mRNA COVID-19 were an independent negative predictor of antibody responses, in addition to other factors. Our results highlight the importance of mental health at the time of vaccination to achieve the higher antibody responses necessary to acquire humoral immunity.
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Kalinichenko LS, Kornhuber J, Müller CP. Individual differences in inflammatory and oxidative mechanisms of stress-related mood disorders. Front Neuroendocrinol 2019; 55:100783. [PMID: 31415777 DOI: 10.1016/j.yfrne.2019.100783] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/29/2019] [Revised: 08/05/2019] [Accepted: 08/09/2019] [Indexed: 12/16/2022]
Abstract
Emotional stress leads to the development of peripheral disorders and is recognized as a modifiable risk factor for psychiatric disorders, particularly depression and anxiety. However, not all individuals develop the negative consequences of emotional stress due to different stress coping strategies and resilience to stressful stimuli. In this review, we discuss individual differences in coping styles and the potential mechanisms that contribute to individual vulnerability to stress, such as parameters of the immune system and oxidative state. Initial differences in inflammatory and oxidative processes determine resistance to stress and stress-related disorders via the alteration of neurotransmitter content in the brain and biological fluids. Differences in coping styles may serve as possible predictors of resistance to stress and stress-related disorders, even before stressful conditions. The investigation of natural variabilities in stress resilience may allow the development of new methods for preventive medicine and the personalized treatment of stress-related conditions.
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Affiliation(s)
- L S Kalinichenko
- Department of Psychiatry and Psychotherapy, University Clinic, Friedrich-Alexander-University of Erlangen-Nuremberg, Schwabachanlage 6, 91054 Erlangen, Germany.
| | - J Kornhuber
- Department of Psychiatry and Psychotherapy, University Clinic, Friedrich-Alexander-University of Erlangen-Nuremberg, Schwabachanlage 6, 91054 Erlangen, Germany
| | - C P Müller
- Department of Psychiatry and Psychotherapy, University Clinic, Friedrich-Alexander-University of Erlangen-Nuremberg, Schwabachanlage 6, 91054 Erlangen, Germany
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Abildgaard A, Elfving B, Hokland M, Lund S, Wegener G. Probiotic treatment protects against the pro-depressant-like effect of high-fat diet in Flinders Sensitive Line rats. Brain Behav Immun 2017; 65:33-42. [PMID: 28450222 DOI: 10.1016/j.bbi.2017.04.017] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/27/2017] [Revised: 04/10/2017] [Accepted: 04/23/2017] [Indexed: 12/18/2022] Open
Abstract
Major depressive disorder (MDD) is highly associated with dysmetabolic conditions, such as obesity and diabetes mellitus type 2, and the gut microbiota may interact with both disease entities. We have previously shown that a high-fat diet (HFD) exacerbated depressive-like behaviour uniquely in Flinders Sensitive Line (FSL) rats that inherently present with an increased level of depressive-like behaviour compared with Flinders Resistant Line (FRL) rats. We therefore investigated whether multispecies probiotics possessed anti-depressant-like effect in FSL rats or protected against the pro-depressant-like effect of HFD. We also examined blood and cerebral T cell subsets as well as plasma cytokines. Lastly, we investigated the effect of HFD in outbred Sprague-Dawley (SD) rats to substantiate the association between depressive-like behaviour and any immunological measures affected by HFD. HFD exacerbated the depressive-like behaviour in FSL rats in the forced swim test, whereas SD rats remained unaffected. Probiotic treatment completely precluded the pro-depressant-like effect of HFD, but it did not affect FSL rats on control diet. Cerebral T lymphocyte CD4/8 ratios closely mirrored the behavioural changes, whereas the proportions of Treg and Th17 subsets were unaltered. No association between blood and brain CD4/8 ratios were evident; nor did plasma cytokine levels change as a consequence of HFD of probiotic treatment. Our findings suggest that MDD may hold a dysmetabolic component that responds to probiotic treatment. This finding has wide implications owing to the high metabolic comorbidity in MDD. Furthermore, the close association between depressive-like behaviour and cerebral T cell populations demonstrate lymphocyte-brain interactions as a promising future research area in the field of psychoneuroimmunology.
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Affiliation(s)
- Anders Abildgaard
- Translational Neuropsychiatry Unit, Aarhus University, Skovagervej 2, 8240 Risskov, Denmark; Department of Clinical Biochemistry, Aarhus University Hospital, Palle Juul-Jensens Boulevard 99, 8200 Aarhus N, Denmark.
| | - Betina Elfving
- Translational Neuropsychiatry Unit, Aarhus University, Skovagervej 2, 8240 Risskov, Denmark
| | - Marianne Hokland
- Department of Biomedicine, Aarhus University, Bartholins Allé 6, Build. 1242, 8000 Aarhuc C, Denmark
| | - Sten Lund
- Department of Medical Endocrinology (MEA), Aarhus University Hospital, Nørrebrogade 44, 8000 Aarhus C, Denmark
| | - Gregers Wegener
- Translational Neuropsychiatry Unit, Aarhus University, Skovagervej 2, 8240 Risskov, Denmark; Center of Excellence for Pharmaceutical Sciences, North-West University (Potchefstroom Campus), Hoffman Street, Potchefstroom 2520, South Africa
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Expression of inflammatory markers in a genetic rodent model of depression. Behav Brain Res 2015; 281:348-57. [DOI: 10.1016/j.bbr.2014.09.025] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2014] [Revised: 08/20/2014] [Accepted: 09/15/2014] [Indexed: 12/11/2022]
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Malki K, Keers R, Tosto MG, Lourdusamy A, Carboni L, Domenici E, Uher R, McGuffin P, Schalkwyk LC. The endogenous and reactive depression subtypes revisited: integrative animal and human studies implicate multiple distinct molecular mechanisms underlying major depressive disorder. BMC Med 2014; 12:73. [PMID: 24886127 PMCID: PMC4046519 DOI: 10.1186/1741-7015-12-73] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/13/2013] [Accepted: 04/10/2014] [Indexed: 12/21/2022] Open
Abstract
BACKGROUND Traditional diagnoses of major depressive disorder (MDD) suggested that the presence or absence of stress prior to onset results in either 'reactive' or 'endogenous' subtypes of the disorder, respectively. Several lines of research suggest that the biological underpinnings of 'reactive' or 'endogenous' subtypes may also differ, resulting in differential response to treatment. We investigated this hypothesis by comparing the gene-expression profiles of three animal models of 'reactive' and 'endogenous' depression. We then translated these findings to clinical samples using a human post-mortem mRNA study. METHODS Affymetrix mouse whole-genome oligonucleotide arrays were used to measure gene expression from hippocampal tissues of 144 mice from the Genome-based Therapeutic Drugs for Depression (GENDEP) project. The study used four inbred mouse strains and two depressogenic 'stress' protocols (maternal separation and Unpredictable Chronic Mild Stress) to model 'reactive' depression. Stress-related mRNA differences in mouse were compared with a parallel mRNA study using Flinders Sensitive and Resistant rat lines as a model of 'endogenous' depression. Convergent genes differentially expressed across the animal studies were used to inform candidate gene selection in a human mRNA post-mortem case control study from the Stanley Brain Consortium. RESULTS In the mouse 'reactive' model, the expression of 350 genes changed in response to early stresses and 370 in response to late stresses. A minimal genetic overlap (less than 8.8%) was detected in response to both stress protocols, but 30% of these genes (21) were also differentially regulated in the 'endogenous' rat study. This overlap is significantly greater than expected by chance. The VAMP-2 gene, differentially expressed across the rodent studies, was also significantly altered in the human study after correcting for multiple testing. CONCLUSIONS Our results suggest that 'endogenous' and 'reactive' subtypes of depression are associated with largely distinct changes in gene-expression. However, they also suggest that the molecular signature of 'reactive' depression caused by early stressors differs considerably from that of 'reactive' depression caused by late stressors. A small set of genes was consistently dysregulated across each paradigm and in post-mortem brain tissue of depressed patients suggesting a final common pathway to the disorder. These genes included the VAMP-2 gene, which has previously been associated with Axis-I disorders including MDD, bipolar depression, schizophrenia and with antidepressant treatment response. We also discuss the implications of our findings for disease classification, personalized medicine and case-control studies of MDD.
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Affiliation(s)
- Karim Malki
- King’s College London, MRC Social, Genetic and Developmental Psychiatry Centre, at Institute of Psychiatry, SGDP Research Centre (PO80), De Crespigny Park, Denmark Hill, London SE5 8AF, UK
| | - Robert Keers
- King’s College London, MRC Social, Genetic and Developmental Psychiatry Centre, at Institute of Psychiatry, SGDP Research Centre (PO80), De Crespigny Park, Denmark Hill, London SE5 8AF, UK
| | - Maria Grazia Tosto
- King’s College London, MRC Social, Genetic and Developmental Psychiatry Centre, at Institute of Psychiatry, SGDP Research Centre (PO80), De Crespigny Park, Denmark Hill, London SE5 8AF, UK
- Department of Psychology, University of York, York, UK
| | | | - Lucia Carboni
- Department of Pharmacy and Biotechnology, Alma Mater Studiorum, University of Bologna, Bologna, Italy
| | - Enrico Domenici
- Center of Excellence for Drug Discovery in Neuroscience, GlaxoSmithKline Medicines Research Centre, Verona, Italy
- Current address: Pharma Research and Early Development, F. Hoffmann–La Roche, Basel, Switzerland
| | - Rudolf Uher
- King’s College London, MRC Social, Genetic and Developmental Psychiatry Centre, at Institute of Psychiatry, SGDP Research Centre (PO80), De Crespigny Park, Denmark Hill, London SE5 8AF, UK
- Department of Psychiatry, Dalhousie University, Halifax, NS, Canada
| | - Peter McGuffin
- King’s College London, MRC Social, Genetic and Developmental Psychiatry Centre, at Institute of Psychiatry, SGDP Research Centre (PO80), De Crespigny Park, Denmark Hill, London SE5 8AF, UK
| | - Leonard C Schalkwyk
- King’s College London, MRC Social, Genetic and Developmental Psychiatry Centre, at Institute of Psychiatry, SGDP Research Centre (PO80), De Crespigny Park, Denmark Hill, London SE5 8AF, UK
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Ashmarin IP, Danilova RA, Rud'ko OI, Belopolskaya MV, Obukhova MF, Shmalgausen EV. An Immunochemical Approach to Model and Long-Term Suppression of Depressive and Anxiety Behavior. SPANISH JOURNAL OF PSYCHOLOGY 2014; 9:219-27. [PMID: 17120701 DOI: 10.1017/s1138741600006119] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
The inhibitor of monoaminooxydase isatin and the ligand of B-receptors cholecystokinin-4 play a significant role in the suppression and induction of depressive and anxiety states. We induced the formation of auto-antibodies to these compounds against their conjugates with antigen-carrier by immunization of white rats. The result was long-term (more than 2 months) stimulation of depressive and anxiety behavior after immunization to isatin and, in contrast, the suppression of such behavior after immunization to cholecystokinin. The perspective of immunochemical approach to long-term correction of behavior is discussed.
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Affiliation(s)
- Igor P Ashmarin
- Dept. of Human Physiology, School of Biology, Moscow State University, Vorobiovy Gory, Moscow 119922, Russia.
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Knapp DJ, Daws LC, Overstreet DH. Behavioral Characteristics of Pharmacologically Selected Lines of Rats: Relevance to Depression. ACTA ACUST UNITED AC 2014. [DOI: 10.4236/wjns.2014.43026] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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Kawai R, Ito S, Aida T, Hattori H, Kimura T, Furukawa T, Mori K, Sanbuissho A, Kawada T. Evaluation of primary and secondary responses to a T-cell-dependent antigen, keyhole limpet hemocyanin, in rats. J Immunotoxicol 2012; 10:40-8. [DOI: 10.3109/1547691x.2012.691122] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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Effects of Chronic Fluoxetine Treatment on Catalepsy and the Immune Response in Mice with a Genetic Predisposition to Freezing Reactions: The Roles of Types 1A and 2A Serotonin Receptors and the tph2 and SERT Genes. ACTA ACUST UNITED AC 2010; 40:521-7. [DOI: 10.1007/s11055-010-9291-7] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2008] [Accepted: 10/20/2008] [Indexed: 10/19/2022]
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Ashmarin IP, Danilova RA, Belopolskaya MV, Rudko OI, Obukhova MF, Shmalgausen EV. Induction of autoimmunity against endogenous neuroregulators isatin and cholecystokinin as a method of modeling and correction of depressive behavior. NEUROCHEM J+ 2007. [DOI: 10.1134/s1819712407020043] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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Overstreet DH, Friedman E, Mathé AA, Yadid G. The Flinders Sensitive Line rat: a selectively bred putative animal model of depression. Neurosci Biobehav Rev 2005; 29:739-59. [PMID: 15925699 DOI: 10.1016/j.neubiorev.2005.03.015] [Citation(s) in RCA: 272] [Impact Index Per Article: 14.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
The Flinders Sensitive Line (FSL) rats were originally selectively bred for increased responses to an anticholinesterase agent. The FSL rat partially resembles depressed individuals because it exhibits reduced appetite and psychomotor function but exhibits normal hedonic responses and cognitive function. The FSL rat also exhibits sleep and immune abnormalities that are observed in depressed individuals. Neurochemical and/or pharmacological evidence suggests that the FSL rat exhibits changes consistent with the cholinergic, serotonergic, dopaminergic, NPY, and circadian rhythm models but not the noradrenergic, HPA axis or GABAergic models of depression. However, evidence for the genetic basis of these changes is lacking and it remains to be determined which, if any, of the neurochemical changes are primary to the behavioral alterations. The FSL rat model has been very useful as a screen for antidepressants because known antidepressants reduced swim test immobility when given chronically and psychomotor stimulants did not. Furthermore, rolipram and a melatonin agonist were shown to have anti-immobility effects in the FSL rats and later to have antidepressant effects in humans. Thus, the FSL rat model of depression exhibits some behavioral, neurochemical, and pharmacological features that have been reported in depressed individuals and has been very effective in detecting antidepressants.
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Affiliation(s)
- David H Overstreet
- Department of Psychiatry, Skipper Bowler Center for Alcohol Studies, University of North Carolina at Chapel Hill, CB #7178, Thurston-Bowles Bldg 3009, Chapel Hill, NC 27599-7178, USA.
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Prior T, Hernandez J, Tougas G, Rangachari PK. Phenotypic differences in cholinergic responses of distal colonic epithelium. Exp Physiol 2004; 89:209-17. [PMID: 15123550 DOI: 10.1113/expphysiol.2003.026989] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
The Flinders sensitive line (FSL) rats exhibit an increased cholinergic responsiveness in vivo when compared to their counterparts, the Flinders resistant line (FRL) rats. The functional consequences of this phenotypic difference on colonic mucosal function are not known. We sought to determine whether isolated distal colonic mucosa from the two strains exhibit differential responses to cholinergic agonists. The responses of the distal colonic mucosa from two lines of rats to carbachol were compared by recording changes in short-circuit current. The ion movements associated with these changes were assessed by flux analysis of the radiotracers, 22Na and 36Cl. The anticipated hyper-responsiveness to cholinergic stimulation in FSL rats was not seen. Carbachol responses were significantly enhanced by indomethacin pretreatment only in FRL rats. Tetrodotoxin (TTX) pretreatment significantly reduced responses to carbachol in FSL rats at all concentrations tested, though this was only seen with lower concentrations in FRL rats. Flux analysis indicated that both lines absorbed Na+ and Cl- under basal conditions and that a significant residual flux was present. Stimulation with carbachol led to significant reductions in net Na+ and Cl- fluxes in both lines. The changes in net Na+ and Cl- flux in both lines stem largely from a decrease in mucosal to serosal fluxes of both ions with an increase in serosal to mucosal flux of Cl-. The striking difference is the significant reduction in residual flux seen only in FRL rats. Indomethacin pretreatment abolished the changes in residual flux seen in FRL rats. Thus the responses to carbachol in these rats had at least three components: (a) a direct effect on the transporting colonocyte, (b) an indirect effect mediated by an arachidonic acid metabolite, and (c) another indirect effect involving a neurotransmitter. The relative contributions of each of these components were different in the two lines.
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Affiliation(s)
- T Prior
- Intestinal Diseases Research Programme, McMaster University, Hamilton, Ontario, Canada
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Overstreet DH, Daws LC, Yadid G, Friedman E, Mathé AA, Janowsky DS. Comment on "preclinical models: status of basic research in depression". Biol Psychiatry 2003; 53:268-70; author reply 270. [PMID: 12559663 DOI: 10.1016/s0006-3223(02)01869-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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Beaugé LA, DiPolo R. Sidedness of the ATP-Na+-K+ interactions with the Na+ pump in squid axons. Methods Mol Biol 1979; 829:125-44. [PMID: 222318 DOI: 10.1007/978-1-61779-458-2_7] [Citation(s) in RCA: 169] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
Using dialysed squid axons we have been able to control internal and external ionic compositions under conditions in which most of the Na+ efflux goes through the Na+ pump. We found that (i) internal K+ had a strong inhibitory effect on Na+ efflux; this effect was antagonized by ATP, with low affinity, and by internal Na+, (ii) a reduction in ATP levels from 3 mM to 50 microM greatly increased the apparent affinity for external K+, but reduced its effectiveness compared with other monovalent cations, as an activator of Na+ efflux, and (iii) the relative effectiveness of different K+ congeners as external activator of the Na+ efflux, though affected by the ATP concentration, was not affected by the Na+/K+ ratio inside the cells. These results are consistent with the idea that the same conformation of the (Na+ + K+)-ATPase can be reached by interaction with external K+ after phosphorylation and with internal K+ before rephosphorylation. They also stress a nonphosphorylating regulatory role of ATP.
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