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Ranson H, Jensen B, Vulule JM, Wang X, Hemingway J, Collins FH. Identification of a point mutation in the voltage-gated sodium channel gene of Kenyan Anopheles gambiae associated with resistance to DDT and pyrethroids. INSECT MOLECULAR BIOLOGY 2000; 9:491-497. [PMID: 11029667 DOI: 10.1046/j.1365-2583.2000.00209.x] [Citation(s) in RCA: 435] [Impact Index Per Article: 17.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
A field trial of permethrin-impregnated bednets and curtains was initiated in Western Kenya in 1990, and a strain of Anopheles gambiae showing reduced susceptibility to permethrin was colonized from this site in 1992. A leucine-phenylalanine substitution at position 1014 of the voltage-gated sodium channel is associated with resistance to permethrin and DDT in many insect species, including Anopheles gambiae from West Africa. We cloned and sequenced a partial sodium channel cDNA from the Kenyan permethrin-resistant strain and we identified an alternative substitution (leucine to serine) at the same position, which is linked to the inheritance of permethrin resistance in the F(2) progeny of genetic crosses between susceptible and resistant individuals. The diagnostic polymerase chain reaction (PCR) developed by Martinez-Torres et al. [(1998) Insect Mol Biol 7: 179-184] to detect kdr alleles in field populations of An. gambiae will not detect the Kenyan allele and hence reliance on this assay may lead to an underestimate of the prevalence of pyrethroid resistance in this species. We adapted the diagnostic PCR to detect the leucine-serine mutation and with this diagnostic we were able to demonstrate that this kdr allele was present in individuals collected from the Kenyan trial site in 1986, prior to the introduction of pyrethroid-impregnated bednets. The An. gambiae sodium channel was physically mapped to chromosome 2L, division 20C. This position corresponds to the location of a major quantitative trait locus determining resistance to permethrin in the Kenyan strain of An. gambiae.
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435 |
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Anderson KF, Lonsway DR, Rasheed JK, Biddle J, Jensen B, McDougal LK, Carey RB, Thompson A, Stocker S, Limbago B, Patel JB. Evaluation of methods to identify the Klebsiella pneumoniae carbapenemase in Enterobacteriaceae. J Clin Microbiol 2007; 45:2723-5. [PMID: 17581941 PMCID: PMC1951220 DOI: 10.1128/jcm.00015-07] [Citation(s) in RCA: 275] [Impact Index Per Article: 15.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The Klebsiella pneumoniae carbapenem (KPC) beta-lactamase occurs in Enterobacteriaceae and can confer resistance to all beta-lactam agents including carbapenems. The enzyme may confer low-level carbapenem resistance, and the failure of susceptibility methods to identify this resistance has been reported. Automated and nonautomated methods for carbapenem susceptibility were evaluated for identification of KPC-mediated resistance. Ertapenem was a more sensitive indicator of KPC resistance than meropenem and imipenem independently of the method used. Carbapenemase production could be confirmed with the modified Hodge test.
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Journal Article |
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275 |
3
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Ranson H, Rossiter L, Ortelli F, Jensen B, Wang X, Roth CW, Collins FH, Hemingway J. Identification of a novel class of insect glutathione S-transferases involved in resistance to DDT in the malaria vector Anopheles gambiae. Biochem J 2001; 359:295-304. [PMID: 11583575 PMCID: PMC1222147 DOI: 10.1042/0264-6021:3590295] [Citation(s) in RCA: 195] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
The sequence and cytological location of five Anopheles gambiae glutathione S-transferase (GST) genes are described. Three of these genes, aggst1-8, aggst1-9 and aggst1-10, belong to the insect class I family and are located on chromosome 2R, in close proximity to previously described members of this gene family. The remaining two genes, aggst3-1 and aggst3-2, have a low sequence similarity to either of the two previously recognized classes of insect GSTs and this prompted a re-evaluation of the classification of insect GST enzymes. We provide evidence for seven possible classes of insect protein with GST-like subunits. Four of these contain sequences with significant similarities to mammalian GSTs. The largest novel insect GST class, class III, contains functional GST enzymes including two of the A. gambiae GSTs described in this report and GSTs from Drosophila melanogaster, Musca domestica, Manduca sexta and Plutella xylostella. The genes encoding the class III GST of A. gambiae map to a region of the genome on chromosome 3R that contains a major DDT [1,1,1-trichloro-2,2-bis-(p-chlorophenyl)ethane] resistance gene, suggesting that this gene family is involved in GST-based resistance in this important malaria vector. In further support of their role in resistance, we show that the mRNA levels of aggst3-2 are approx. 5-fold higher in a DDT resistant strain than in the susceptible strain and demonstrate that recombinant AgGST3-2 has very high DDT dehydrochlorinase activity.
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research-article |
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195 |
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Atkinson KD, Jensen B, Kolat AI, Storm EM, Henry SA, Fogel S. Yeast mutants auxotrophic for choline or ethanolamine. J Bacteriol 1980; 141:558-64. [PMID: 6988386 PMCID: PMC293659 DOI: 10.1128/jb.141.2.558-564.1980] [Citation(s) in RCA: 161] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023] Open
Abstract
Three mutants of the yeast Saccharomyces cerevisiae which require exogenous ethanolamine or choline were isolated. The mutants map to a single locus (cho1) on chromosome V. The lipid composition suggests that cho1 mutants do not synthesize phosphatidylserine under any growth conditions. If phosphatidylethanolamine or phosphatidylcholine, which are usually derived from phosphatidylserine, were synthesized from exogenous ethanolamine or choline, the mutants grew and divided relatively normally. However, mitochondrial abnormalities were evident even when ethanolamine and choline were supplied. Diploids homozygous for the cho1 mutation were defective in sporulation. Growth on nonfermentable carbon sources was slow, and a high proportion of respiratory-deficient (petite) cells were generated in cho1 cultures.
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research-article |
45 |
161 |
5
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Olsen SF, Hansen HS, Sørensen TI, Jensen B, Secher NJ, Sommer S, Knudsen LB. Intake of marine fat, rich in (n-3)-polyunsaturated fatty acids, may increase birthweight by prolonging gestation. Lancet 1986; 2:367-9. [PMID: 2874370 DOI: 10.1016/s0140-6736(86)90055-3] [Citation(s) in RCA: 155] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
Birthweights in the Faroe Islands are among the highest in the world. Compared with Denmark, the average birthweight of liveborn singleton infants of primiparous mothers is 194 g higher, and a substantial part of this difference seems to be attributable to longer gestation. Prostaglandins play an important part in the timing of parturition in human beings. Dietary (n-3)-polyunsaturated fatty acids (PUFA) in high amounts influence endogenous prostaglandin metabolism. Owing to the large consumption of marine fat, the average intake of (n-3)-PUFA in the Faroes by far exceeds that in Denmark. The hypothesis proposed is that dietary (n-3)-PUFA in high amounts prolong gestation in human beings by interfering with uterine production of prostaglandins, possibly by inhibiting the production of dienoic prostaglandins, primarily PGF2 alpha and PGE2, which are mediators of uterine contractions and cervical ripening.
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39 |
155 |
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Hansen PB, Jensen BL, Andreasen D, Skøtt O. Differential expression of T- and L-type voltage-dependent calcium channels in renal resistance vessels. Circ Res 2001; 89:630-8. [PMID: 11577029 DOI: 10.1161/hh1901.097126] [Citation(s) in RCA: 153] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
The distribution of voltage-dependent calcium channels in kidney pre- and postglomerular resistance vessels was determined at the molecular and functional levels. Reverse transcription-polymerase chain reaction analysis of microdissected rat preglomerular vessels and cultured smooth muscle cells showed coexpression of mRNAs for T-type subunits (Ca(V)3.1, Ca(V)3.2) and for an L-type subunit (Ca(V)1.2). The same expression pattern was observed in juxtamedullary efferent arterioles and outer medullary vasa recta. No calcium channel messages were detected in cortical efferent arterioles. Ca(V)1.2 protein was demonstrated by immunochemical labeling of rat preglomerular vasculature and juxtamedullary efferent arterioles and vasa recta. Cortical efferent arterioles were not immunopositive. Recordings of intracellular calcium concentration with digital fluorescence imaging microscopy showed a significant increase of calcium in response to K(+) (100 mmol/L) in isolated afferent arterioles (140+/-25%) and in juxtamedullary efferent arterioles (118+/-21%). These calcium responses were attenuated by the L-type antagonist calciseptine and by the T-type antagonist mibefradil. Intracellular calcium increased in response to K(+) in cortical efferent arterioles (21+/-9%). Mibefradil and nickel concentration dependently blocked K(+)-induced contraction of perfused rabbit afferent arterioles. Calciseptine blocked the contraction mediated by K(+) (EC(50) 8x10(-14)). S-(-)-Bay K 8644 had no effect on vascular diameter in the afferent arteriole. We conclude that voltage-dependent L- and T-type calcium channels are expressed and of functional significance in renal cortical preglomerular vessels, in juxtamedullary efferent arterioles, and in outer medullary vasa recta, but not in cortical efferent arterioles.
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MESH Headings
- Animals
- Arterioles/drug effects
- Arterioles/physiology
- Calcium/metabolism
- Calcium Channel Agonists/pharmacology
- Calcium Channel Blockers/pharmacology
- Calcium Channels, L-Type/genetics
- Calcium Channels, L-Type/metabolism
- Calcium Channels, T-Type/genetics
- Calcium Channels, T-Type/metabolism
- Cell Separation
- Cells, Cultured
- Immunohistochemistry
- In Vitro Techniques
- Intracellular Fluid/metabolism
- Kidney/blood supply
- Kidney/cytology
- Kidney/metabolism
- Kidney Glomerulus/blood supply
- Kidney Glomerulus/cytology
- Male
- Muscle, Smooth, Vascular/cytology
- Muscle, Smooth, Vascular/drug effects
- Muscle, Smooth, Vascular/metabolism
- Nickel/pharmacology
- Organ Specificity
- Potassium/pharmacology
- Protein Subunits
- RNA, Messenger/metabolism
- Rabbits
- Rats
- Vascular Resistance/physiology
- Vasodilator Agents/pharmacology
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24 |
153 |
7
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Abstract
A new method for quantitating the numbers of mutans streptococci in saliva--the "Strip mutans" test--was developed. It includes the following steps: A prepared plastic spatula is contaminated with saliva, transferred to a selective broth, incubated for two days, and dried. A predetermined area is counted or evaluated for CFUs of mutans streptococci. The medium contains sucrose to promote adhesion of mutans streptococci to the strip. Bacitracin, added just before use, is the basis for the selectivity. Results with the new medium were compared with those from the "spatula technique" and with those from conventional saliva sampling with dilution. The studies involved 302 and 60 schoolchildren, respectively. There was a highly significant correlation between the results from the new method and those from conventional methods. The strip mutans test is easy to used and has long shelf-life, and the spatulas with adherent colonies can be saved for future comparisons.
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Comparative Study |
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Røgind H, Bibow-Nielsen B, Jensen B, Møller HC, Frimodt-Møller H, Bliddal H. The effects of a physical training program on patients with osteoarthritis of the knees. Arch Phys Med Rehabil 1998; 79:1421-7. [PMID: 9821904 DOI: 10.1016/s0003-9993(98)90238-6] [Citation(s) in RCA: 147] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
OBJECTIVE To investigate physical function in patients with severe osteoarthritis (OA) of the knees during and after a general physical training program. DESIGN Randomized control trial, blinded observer, follow-up at 3 months and 1 year. SETTING Outpatient clinic. PATIENTS Consecutive sample of 25 patients (3 men, 22 women) with OA of the knees according to the criteria of the American College of Rheumatology (ACR). Two patients (8%) failed to complete the study. There were no withdrawals for adverse effects. INTERVENTION Twelve patients received training in groups of 6, twice a week for 3 months. Training focused on general fitness, balance, coordination, stretching, and lower extremity muscle strength, and included a daily home exercise program. MAIN OUTCOME MEASURES Muscle strength across the knee (extension and flexion), Algofunctional Index (AFI), pain (0 to 10 point scale), walking speed, clinical findings. RESULTS Patients participated in 96 of 96 assessments (100%) and in 218 of 280 training sessions (77.9%). From baseline to 3 months, isokinetic quadriceps strength (30 degrees/sec) improved 20% (confidence interval [CI] 2alpha = .05, 8% to 50%) in the least affected leg; isometric strength improved 21%. By 1 year, AFI had decreased 3.8 points (CI2alpha = .05, 1.0 to 7.0), pain had decreased 2.0 points (CI2alpha = 05, 0.0 to 4.0), and walking speed had increased 13% (CI2alpha = .05, 4% to 23%). There was an increase in the frequency of palpable joint effusions (p < .01) on the most affected side. Frequency of crepitus decreased on the least affected side (p < .01). CONCLUSIONS General physical training appears to be beneficial to patients with OA of the knee. As shown by the high compliance and low dropout frequency, such a program is feasible even in patients with severe OA of the knee.
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Clinical Trial |
27 |
147 |
9
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Abstract
The purpose of the present investigation was to describe the formation, maturation and eruption of the dentition, including supernumerary teeth in a sample of patients with cleidocranial dysplasia. The dentition was evaluated from orthopantomograms, intraoral radiographs, cephalometric films, surgically removed teeth and intraoral photographs in 19 patients (9 men, 10 women), aged 3.5 to 34 years. Formation of primary teeth was normal, whereas all patients but one had supernumerary permanent teeth. Frequency of supernumerary teeth ranged from 22% in the maxillary incisor region to 5% in the molar regions. Supernumerary teeth were formed lingually and occlusally to the normal teeth. Maturation of the primary dentition was normal, while permanent teeth were delayed from 1 to 4 yr. Supernumerary teeth were delayed about 4 years in relation to normal permanent teeth. Eruption of primary teeth was normal, whereas all patients had severe eruption problems of permanent teeth. It was hypothesized that the dental lamina for both primary and permanent dentition is normal, but does not resolve completely and therefore may form supernumerary teeth. Abnormalities of tooth morphology is related to inadequate space and arrested eruption. Delayed or arrested eruption is probably caused by diminished resorption of bone and of primary teeth and to the presence of multiple supernumerary teeth.
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35 |
147 |
10
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Sreedharan S, Oram M, Jensen B, Peterson LR, Fisher LM. DNA gyrase gyrA mutations in ciprofloxacin-resistant strains of Staphylococcus aureus: close similarity with quinolone resistance mutations in Escherichia coli. J Bacteriol 1990; 172:7260-2. [PMID: 2174869 PMCID: PMC210851 DOI: 10.1128/jb.172.12.7260-7262.1990] [Citation(s) in RCA: 136] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
The gyrA genes isolated from three ciprofloxacin-resistant clinical isolates of Staphylococcus aureus carried codon 84 (serine----leucine) and/or codon 85 (serine----proline) mutations that were absent in pretreatment susceptible strains. These substitutions occur in a region of the gyrase A protein wherein directly analogous mutations of serine 83----leucine and alanine 84----proline in Escherichia coli confer quinolone resistance. Thus, DNA gyrase A subunit mutations are implicated in resistance to ciprofloxacin in S. aureus.
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research-article |
35 |
136 |
11
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Hansen HS, Jensen B. Essential function of linoleic acid esterified in acylglucosylceramide and acylceramide in maintaining the epidermal water permeability barrier. Evidence from feeding studies with oleate, linoleate, arachidonate, columbinate and alpha-linolenate. BIOCHIMICA ET BIOPHYSICA ACTA 1985; 834:357-63. [PMID: 3922424 DOI: 10.1016/0005-2760(85)90009-8] [Citation(s) in RCA: 135] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Essential fatty acid-deficient rats were supplemented with 300 mg per day of pure fatty acid esters: oleate (O), linoleate (L), arachidonate (A), and columbinate (C) for 10 days. During this period, the rats in groups L, A, and C all showed a decrease in their initially high trans-epidermal water loss, a classical essential fatty acid-deficiency symptom, to a level seen in non-deficient rats (group N). The trans-epidermal water loss in rats of group O was unaffected by the supplementation. Fatty acid composition of two epidermal sphingolipids, acylglucosylceramide and acylceramide, from the skin were determined. The results indicate that re-establishment of a low trans-epidermal water loss was associated with incorporation of linolenate into the two epidermal sphingolipids. Supplementation with columbinate resulted in relatively high amounts of this fatty acid in the investigated epidermal sphingolipids. Analysis of pooled skin specimens from a previous study in which weanling rats were fed a fat-free diet and supplemented orally with pure alpha-linolenate for 13 weeks (Hansen, H.S. and Jensen, B. (1983) Lipids 18, 682-690) revealed very little polyunsaturated fatty acid in the two sphingolipids. These rats showed increased evaporation which was comparable to that of essential fatty acid-deficient rats. We interpret these results as strong evidence for a very specific and essential function of linoleic acid in maintaining the integrity of the epidermal water permeability barrier. This function of linoleate is independent of its role as precursor for arachidonate and icosanoids.
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40 |
135 |
12
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Pedersen C, Lindhardt BO, Jensen BL, Lauritzen E, Gerstoft J, Dickmeiss E, Gaub J, Scheibel E, Karlsmark T. Clinical course of primary HIV infection: consequences for subsequent course of infection. BMJ (CLINICAL RESEARCH ED.) 1989; 299:154-7. [PMID: 2569901 PMCID: PMC1837064 DOI: 10.1136/bmj.299.6692.154] [Citation(s) in RCA: 126] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
OBJECTIVE To investigate the impact of the clinical course of the primary HIV infection on the subsequent course of the infection. DESIGN Prospective documenting of seroconversion, follow up at six month intervals, and analysis of disease progression by life tables. PATIENTS 86 Men in whom seroconversion occurred within 12 months. PRIMARY OUTCOME MEASURE Progression of HIV infection, defined as CD4 lymphocyte count less than 0.5 X 10(9)/l, recurrence of HIV antigenaemia, or progression to Centers for Disease Control group IV. MAIN RESULTS Median follow up was 670 (range 45-1506) days. An acute illness like glandular fever occurred in 46 (53%) subjects. Three year progression rates to Centers for Disease Control group IV was 78% at three years for those who had longlasting illnesses (duration greater than or equal to 14 days) during seroconversion as compared with 10% for those who were free of symptoms or had mild illness. All six patients who developed AIDS had had longlasting primary illnesses. Three year progression rates to a CD4 lymphocyte count less than 0.5 X 10(9)/l and to recurrence of HIV antigenaemia were significantly higher for those who had longlasting primary illnesses than those who had no symptoms or mild illness (75% v 42% and 55% v 14%, respectively). CONCLUSION The course of primary infection may determine the subsequent course of the infection.
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research-article |
36 |
126 |
13
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Jørgensen K, Fallentin N, Krogh-Lund C, Jensen B. Electromyography and fatigue during prolonged, low-level static contractions. EUROPEAN JOURNAL OF APPLIED PHYSIOLOGY AND OCCUPATIONAL PHYSIOLOGY 1988; 57:316-21. [PMID: 3371340 DOI: 10.1007/bf00635990] [Citation(s) in RCA: 118] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
Findings from five separate studies of EMG changes and muscle fatigue during prolonged low-level static contractions are summarized, and the possible mechanisms behind the changes are briefly discussed. Sustained static contractions (10%, 7% and 5% MVC) of up to 1 h duration were performed by finger flexors, elbow flexors and extensors, and knee extensors. In one experiment, intermittent static arm pulling (triceps) (10 s contraction and 5 s rest, average work load 14% and 10% MVC) was performed for 7 h. The endurance time for the sustained contractions was around one hour for 10% MVC, and it was shown--all in all--that the concept of "indefinite" endurance times at contractions below 15-20% MVC cannot be maintained. After 5% MVC sustained contractions for one hour a 12% reduction in MVC was seen, and significant increases in EMG amplitude and decreases in the mean spectral frequency of the EMG-power spectrum were found. Marked differences were also seen in the EMG changes in the elbow flexors and extensors, and transcutaneous electrical stimulation of the knee extensors showed that low frequency fatigue was present after the contraction. With intermittent contractions similar changes in the EMG parameters were seen after 2-3 h of contractions at 14% MVC. On average, during contractions of 10% MVC no EMG changes were detected. Increased extracellular potassium concentration in the contracting muscles is suggested as a possible explanation of these findings.
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118 |
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Wilson EM, Bial J, Tarlow B, Bial G, Jensen B, Greiner DL, Brehm MA, Grompe M. Extensive double humanization of both liver and hematopoiesis in FRGN mice. Stem Cell Res 2014; 13:404-12. [PMID: 25310256 PMCID: PMC7275629 DOI: 10.1016/j.scr.2014.08.006] [Citation(s) in RCA: 113] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/16/2014] [Revised: 08/21/2014] [Accepted: 08/27/2014] [Indexed: 11/21/2022] Open
Abstract
Preclinical research in animals often fails to adequately predict the outcomes observed in human patients. Chimeric animals bearing individual human tissues have been developed to provide improved models of human-specific cellular processes. Mice transplanted with human hematopoietic stem cells can be used to study human immune responses, infections of blood cells and processes of hematopoiesis. Animals with humanized livers are useful for modeling hepatotropic infections as well as drug metabolism and hepatotoxicity. However, many pathophysiologic processes involve both the liver and the hematolymphoid system. Examples include hepatitis C/HIV co-infection, immune mediated liver diseases, liver injuries with inflammation such as steatohepatitis and alcoholic liver disease. We developed a robust protocol enabling the concurrent double-humanization of mice with mature hepatocytes and human blood. Immune-deficient, fumarylacetoacetate hydrolase (Fah−/−), Rag2−/− and Il2rg−/− deficient animals on the NOD-strain background (FRGN) were simultaneously co-transplanted with adult human hepatocytes and hematopoietic stem cells after busulfan and Ad:uPA pre-conditioning. Four months after transplantation the average human liver repopulation exceeded 80% and hematopoietic chimerism also was high (40–80% in bone marrow). Importantly, human macrophages (Kupffer cells) were present in the chimeric livers. Double-chimeric FRGN mice will serve as a new model for disease processes that involve interactions between hepatocytes and hematolymphoid cells.
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Research Support, N.I.H., Extramural |
11 |
113 |
15
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Reuter S, Jensen B, Buttenschoen K, Kratzer W, Kern P. Benzimidazoles in the treatment of alveolar echinococcosis: a comparative study and review of the literature. J Antimicrob Chemother 2000; 46:451-6. [PMID: 10980173 DOI: 10.1093/jac/46.3.451] [Citation(s) in RCA: 107] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Mebendazole and albendazole are the drugs of choice for the treatment of alveolar echinococcosis. In this open-labelled observational study we present and evaluate the outcome of long-term treatment with these drugs and present results of different treatment regimens. Thirty-five patients were started on either mebendazole or albendazole at the beginning of 1992 and followed for an average of 39 months (range 12-79 months). Treatment was classed as successful if the disease had not progressed for >1 year and if there were no side-effects necessitating a change of treatment. Lack of progression was evaluated mainly using ultrasound and computed tomography and was further substantiated by laboratory tests and clinical findings. The overall success rate was 97%. An initial regimen for cases of alveolar echinococcosis was recurrence-free in 71% of those treated with mebendazole and in 78% of those treated with albendazole. Four out of five cases with progressive disease stabilized after the therapeutic regimen was changed. Seven patients received a continuous regimen with albendazole. These patients were observed over an average of 28 months (range 13-50 months) without signs of progression or significant side-effects. This open-labelled prospective study demonstrates the high therapeutic efficacy of both mebendazole and albendazole with similar response rates in the treatment of alveolar echinococcosis. Albendazole reduced costs by >40% and is easier for patients to take, further arguing in favour of its preferred use. Albendazole in alveolar echinococcosis is only licensed for intermittent application. None the less, continuous treatment is safe and well tolerated and showed promising results when applied to patients in whom other treatment regimens had failed. It should thus be strongly considered in inoperable cases or progressive disease.
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Clinical Trial |
25 |
107 |
16
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Jensen BL, Kurtz A. Differential regulation of renal cyclooxygenase mRNA by dietary salt intake. Kidney Int 1997; 52:1242-9. [PMID: 9350647 DOI: 10.1038/ki.1997.449] [Citation(s) in RCA: 103] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Experiments were done to investigate the influence of dietary salt intake on renal cyclooxygenase (COX) I and II mRNA levels. To this end rats were fed either a low NaCl diet (LS; 0.02% NaCl wt/wt) or a high NaCl diet (HS diet; 4% NaCl wt/wt) for 5, 10 and 20 days. After 10 days Na excretion differed 760-fold, plasma renin activity and renin mRNA were increased eight- and threefold in LS compared to HS animals. Total renal COX I mRNA decreased 50% following the LS diet and did not change after the HS diet. Conversely, COX II mRNA declined after HS intake and transiently increased after salt depletion. COX I and II mRNAs were unevenly distributed along the cortical-medullary axis with ratios of the cortex:outer medulla:papilla of 1:3:23 and 1:1:2, respectively. Cortical COX mRNAs were inversely regulated by salt intake with eightfold changes in COX II. Conversely, in medullary zones, COX I mRNA correlated directly with salt intake. We conclude that dietary salt intake influences renal cyclooxygenase mRNAs zone-specifically with opposite responses between cortex and medulla. Cortical COX II-mediated prostaglandin formation is probably important in low salt states whereas medullary COX I-produced prostaglandins seem to be more important for renal adaptation to a high salt intake.
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28 |
103 |
17
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Uhrenholt TR, Schjerning J, Hansen PB, Nørregaard R, Jensen BL, Sorensen GL, Skøtt O. Rapid Inhibition of Vasoconstriction in Renal Afferent Arterioles by Aldosterone. Circ Res 2003; 93:1258-66. [PMID: 14615288 DOI: 10.1161/01.res.0000106135.02935.e1] [Citation(s) in RCA: 103] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Aldosterone has been suggested to elicit vessel contraction via a nongenomic mechanism. We tested this proposal in microdissected, perfused rabbit renal afferent arterioles. Aldosterone had no effect on internal diameter in concentrations from 10(-10) to 10(-5) mol/L, but aldosterone abolished the ability of 100 mmol/L KCl to induce vascular contraction. The inhibitory effect of aldosterone was observed from 1 pmol/L. The inhibitory effect was significant after 5 minutes and maximal after 20 minutes and was fully reversible. Actinomycin D (10(-6) mol/L) prolonged the effect of aldosterone. The effect was abolished by the mineralocorticoid receptor antagonist spironolactone (10(-7) mol/L) but not by the glucocorticoid receptor antagonist mifepristone (10(-6) mol/L). The K+-mediated increase of intracellular calcium concentration in afferent arterioles was not affected by aldosterone. Mineralocorticoid receptor was detected by reverse transcription-polymerase chain reaction and immunohistochemistry in rat renal vasculature and rabbit endothelial cells. Inhibition of phosphatidylinositol (PI)-3 kinase with LY 294002 (3x10(-6) mol/L) restored sensitivity to K+ in the presence of aldosterone, and afferent arterioles were immunopositive for PI-3 kinase subunit p110alpha. Inhibition of NO formation by L-NAME (10(-4) mol/L) or inhibition of soluble guanylyl cyclase with 1H-(1,2,4)Oxadiazolo[4,3-a]quinoxaline-1-one restored K+-induced vasoreactivity in the presence of aldosterone. Similar to aldosterone, the NO donor sodium nitroprusside inhibited K+-induced vascular contraction. Geldanamycin (10(-6) mol/L), an inhibitor of heat shock protein 90, abolished aldosterone-induced vasorelaxation. We conclude that aldosterone inhibits depolarization-induced vasoconstriction in renal afferent arterioles by a rapid nongenomic mechanism that is initiated by mineralocorticoid receptor activation and involves PI-3 kinase, protein kinase B, and heat shock protein 90-mediated stimulation of NO generation.
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MESH Headings
- 11-beta-Hydroxysteroid Dehydrogenase Type 2/genetics
- 11-beta-Hydroxysteroid Dehydrogenase Type 2/metabolism
- Aldosterone/pharmacology
- Animals
- Aorta/drug effects
- Aorta/metabolism
- Arterioles/drug effects
- Arterioles/metabolism
- Arterioles/physiology
- Benzoquinones
- Calcium/metabolism
- Cells, Cultured
- Chromones/pharmacology
- Dactinomycin/pharmacology
- Dose-Response Relationship, Drug
- Endothelium, Vascular/cytology
- Endothelium, Vascular/drug effects
- Endothelium, Vascular/metabolism
- Enzyme Inhibitors/pharmacology
- Gene Expression Regulation/drug effects
- Heart Ventricles/drug effects
- Heart Ventricles/metabolism
- Humans
- In Vitro Techniques
- Kidney/blood supply
- Lactams, Macrocyclic
- Male
- Morpholines/pharmacology
- NG-Nitroarginine Methyl Ester/pharmacology
- Nitric Oxide Donors/pharmacology
- Nitric Oxide Synthase/antagonists & inhibitors
- Nitric Oxide Synthase/metabolism
- Nitroprusside/pharmacology
- Phosphatidylinositol 3-Kinases/metabolism
- Phosphoinositide-3 Kinase Inhibitors
- Potassium/pharmacology
- Protein Serine-Threonine Kinases
- Proto-Oncogene Proteins/metabolism
- Proto-Oncogene Proteins c-akt
- Quinones/pharmacology
- RNA, Messenger/drug effects
- RNA, Messenger/genetics
- RNA, Messenger/metabolism
- Rabbits
- Rats
- Rats, Sprague-Dawley
- Receptors, Mineralocorticoid/genetics
- Receptors, Mineralocorticoid/metabolism
- Spironolactone/pharmacology
- Vasoconstriction/drug effects
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Ranson H, Jensen B, Wang X, Prapanthadara L, Hemingway J, Collins FH. Genetic mapping of two loci affecting DDT resistance in the malaria vector Anopheles gambiae. INSECT MOLECULAR BIOLOGY 2000; 9:499-507. [PMID: 11029668 DOI: 10.1046/j.1365-2583.2000.00214.x] [Citation(s) in RCA: 90] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
Resistance to the insecticide DDT in the mosquito vectors of malaria has severely hampered efforts to control this disease and has contributed to the increase in prevalence of malaria cases seen in recent years. Over 90% of the 300-500 million annual cases of malaria occur in Africa, where the major vector is Anopheles gambiae. DDT resistance in the ZAN/U strain of An. gambiae is associated with an increased metabolism of the insecticide, catalysed by members of the glutathione S-transferase (GST) enzyme family, but the molecular mechanism underlying this metabolic resistance is not known. Genetic crosses show that resistance is autosomal and semidominant. We have used microsatellite markers to identify two quantitative trait loci (QTL), which together explain over 50% of the variance in susceptibility to DDT in the ZAN/U strain of An. gambiae. The first locus, rtd1, is on chromosome 3 between markers H341 and H88 and has a recessive effect with respect to susceptibility. The second locus, rtd2 is on chromosome 2L, close to marker H325 and has an additive genetic effect. The markers flanking these two QTL have been physically mapped to An. gambiae polytene chromosomes. They do not coincide with any of the GST genes that have been cloned and mapped in this species. Characterization of these QTL will lead to a clearer understanding of the mechanisms of metabolic resistance to DDT.
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Hansen PB, Jensen BL, Skott O. Chloride regulates afferent arteriolar contraction in response to depolarization. Hypertension 1998; 32:1066-70. [PMID: 9856975 DOI: 10.1161/01.hyp.32.6.1066] [Citation(s) in RCA: 87] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
-Renal vascular reactivity is influenced by the level of dietary salt intake. Recent in vitro data suggest that afferent arteriolar contractility is modulated by extracellular chloride. In the present study, we assessed the influence of chloride on K+-induced contraction in isolated perfused rabbit afferent arterioles. In 70% of vessels examined, K+-induced contraction was abolished by acute substitution of bath chloride. Consecutive addition of Cl- (30, 60, 80, 100, 110, and 117 mmol/L) restored the sensitivity to K+, and half-maximal response was observed at 82 mmol/L chloride. The calcium channel antagonist diltiazem (10(-6) mol/L) abolished K+-induced contractions. Bicarbonate did not modify the sensitivity to chloride. Norepinephrine (10(-6) mol/L) induced full contraction in depolarized vessels even in the absence of chloride. Iodide and nitrate were substituted for chloride with no inhibitory effect on K+-induced contraction. Approximately 30% of the vessels constricted in response to K+ in the absence of chloride. This response was reversibly blocked by the alpha1-blocker phentolamine (PA) (10(-5) mol/L) and, with PA present, the dependence on chloride was similar to the above series. The results show that K+-induced contraction of smooth muscle cells in the afferent arteriole is highly sensitive to chloride, whereas neurotransmitter release and ensuing contraction is not dependent on chloride. Thus, there are different activation pathways for depolarizing vasoconstrictors and for the sympathetic nervous system in renal afferent arterioles. This could be of physiological relevance for the resetting of afferent arteriolar sensitivity during changes in salt intake.
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Olsen SF, Hansen HS, Secher NJ, Jensen B, Sandström B. Gestation length and birth weight in relation to intake of marine n-3 fatty acids. Br J Nutr 1995; 73:397-404. [PMID: 7766563 DOI: 10.1079/bjn19950042] [Citation(s) in RCA: 80] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
It has been hypothesized that marine n-3 fatty acids ingested during pregnancy prolong duration of pregnancy and increase fetal growth rate in humans. By a combined self-administered questionnaire and interview applied in the 30th week of gestation we assessed dietary intake of marine n-3 fatty acids and energy in a population-based sample of 965 pregnant Danish women; in a random 14% subsample we also measured marine n-3 fatty acids relative to arachidonic acid (FA-ratio) in erythrocytes. Mean intake of marine n-3 fatty acids was 0.25 (95% range 0-0.75) g/d. We could detect no association between n-3 fatty acid intake and FA-ratio on the one hand, and gestation length, birth weight and birth length on the other. The analyses were adjusted for maternal height, prepregnant weight, parity and smoking. The conclusion from the study was that within the intake range of this population, marine n-3 fatty acids ingested in the weeks prior to the 30th week of pregnancy seem not to be a predictor of gestation length or fetal growth rate.
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Olsen SF, Hansen HS, Sommer S, Jensen B, Sørensen TI, Secher NJ, Zachariassen P. Gestational age in relation to marine n-3 fatty acids in maternal erythrocytes: a study of women in the Faroe Islands and Denmark. Am J Obstet Gynecol 1991; 164:1203-9. [PMID: 1827949 DOI: 10.1016/0002-9378(91)90683-i] [Citation(s) in RCA: 75] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Gestation is longer in Faroese than Danish women, possibly because of the high intake of marine long-chain n-3 fatty acids that down regulates formation of prostaglandins from arachidonic acid. Polyunsaturated fatty acids were quantified in erythrocytes obtained within 2 days of delivery from randomly selected groups of 62 Faroese and 37 Danish women with an assessable gestational age. Average ratio of long-chain n-3 fatty acids to arachidonic acid [(3/6) ratio] was 0.73 (SD = 0.11) in Faroese women and 0.61 (SD = 0.12) in Danish women (p less than 0.0001), corresponding to the higher intake of marine n-3 fatty acids in the Faroes. A 20% increase in the (3/6) ratio was associated with an increase in pregnancy duration of 5.7 days in Danish women (95% confidence interval, 1.4 to 10.1 days; p = 0.02) and 0.7 days in Faroese women (95% confidence interval, -2.0 to 3.3; p = 0.6). The hypothesized exposure-effect relationship may be weaker or absent at the higher level of exposure seen in the Faroese group.
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Jensen BL, Schmid C, Kurtz A. Prostaglandins stimulate renin secretion and renin mRNA in mouse renal juxtaglomerular cells. THE AMERICAN JOURNAL OF PHYSIOLOGY 1996; 271:F659-69. [PMID: 8853429 DOI: 10.1152/ajprenal.1996.271.3.f659] [Citation(s) in RCA: 69] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
This study examined 1) effects of prostaglandins (PG) on renin secretion and renin gene expression from isolated juxtaglomerular granular cells and 2) expression of cyclooxygenases in juxtaglomerular structures. Incubation of granular cell cultures with PGE2, -I2, -F2 alpha, and thromboxane B2 identified PGI2 and PGE2 as stimulators of renin secretion; the effects were dose and time dependent. PGE2 also increased renin mRNA accumulation time and dose dependent. PGE2 and PGI2 activated adenylate cyclase concentration dependent in granular cells. PGE2 stimulations of renin secretion and renin mRNA were nonadditive to those of forskolin and were inhibited by endothelin. The findings are compatible with cellular actions through adenosine 3',5'-cyclic monophosphate (cAMP). On total RNA harvested from whole kidneys, from microdisected glomeruli with attached afferent arterioles and from mesangial cells in primary culture, reverse transcription-polymerase chain reaction revealed significant expression of cyclooxygenase I and II. By direct interaction with PG receptors on renal juxtaglomerular cells, PGE2 and PGI2 can act as potent and rapid stimulators of renin secretion and renin mRNA probably through cAMP-dependent pathways.
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Hommel E, Andersen P, Gall MA, Nielsen F, Jensen B, Rossing P, Dyerberg J, Parving HH. Plasma lipoproteins and renal function during simvastatin treatment in diabetic nephropathy. Diabetologia 1992; 35:447-51. [PMID: 1521727 DOI: 10.1007/bf02342442] [Citation(s) in RCA: 67] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
The aim of this study was to assess the effect of simvastatin on plasma lipoproteins and renal function in hypercholesterolaemic Type 1 (insulin-dependent) diabetic patients with diabetic nephropathy. Twenty-six hypercholesterolaemic (total cholesterol greater than or equal to 5.5 mmol/l) Type 1 diabetic patients with nephropathy were enrolled in a double-blind randomized placebo-controlled study for 12 weeks. The active treatment group (n = 14) received simvastatin (10-20 mg/day) for 12 weeks while the remaining 12 patients received treatment with placebo. The results during simvastatin treatment (baseline vs 12 weeks): total cholesterol 6.6 vs 4.8 mmol/l (p less than 0.01), LDL-cholesterol 4.25 vs 2.57 mmol/l (p less than 0.01) and apolipoprotein B 1.37 vs 1.06 mmol/l (p less than 0.01). HDL-cholesterol, and apolipoprotein A-I remained unchanged. Total cholesterol, LDL-cholesterol, HDL-cholesterol, apolipoprotein A-I, apolipoprotein B remained unchanged during placebo treatment. Albuminuria measured during the simvastatin and the placebo treatment (baseline vs 12 weeks) (the data are logarithmically transformed before analysis because of their positively skewed transformation; geometric mean (x/divided by antilog SE) is indicated) was 458 (x/divided by 1.58) vs 393 (x/divided by 1.61) and 481 (x/divided by 1.62) vs 368 (x/divided by 1.78 micrograms/min (NS). Glomerular filtration rate during simvastatin and placebo treatment (baseline vs 12 weeks) was 64 vs 63 and 72 vs 74 ml.min-1.1.73 m-2, respectively. Two patients receiving simvastatin treatment were withdrawn, one due to gastrointestinal side effects and one due to myalgia.(ABSTRACT TRUNCATED AT 250 WORDS)
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Refsgaard HH, Brockhoff PM, Jensen B. Free polyunsaturated fatty acids cause taste deterioration of salmon during frozen storage. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2000; 48:3280-3285. [PMID: 10956102 DOI: 10.1021/jf000021c] [Citation(s) in RCA: 64] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
Increased intensity of train oil taste, bitterness, and metal taste are the most pronounced sensory changes during frozen storage of salmon (Refsgaard, H. H. F.; Brockhoff, P. B.; Jensen, B. Sensory and Chemical Changes in Farmed Atlantic Salmon (Salmo salar) during Frozen Storage. J. Agric. Food Chem. 1998a, 46, 3473-3479). Addition of each of the unsaturated fatty acids: palmitoleic acid (16:1, n - 7), linoleic acid (C18:2, n - 6), eicosapentaenoic acid (EPA; C20:5, n - 3) and docosahexaenoic acid (DHA; C22:6, n - 3) to fresh minced salmon changed the sensory perception and increased the intensity of train oil taste, bitterness, and metal taste. The added level of each fatty acid ( approximately 1 mg/g salmon meat) was equivalent to the concentration of the fatty acids determined in salmon stored as fillet at -10 degrees C for 6 months. The effect of addition of the fatty acids on the intensity of train oil taste, bitterness and metal taste was in the order: DHA > palmitoleic acid > linoleic acid > EPA. Formation of free fatty acids was inhibited by cooking the salmon meat before storage. Furthermore, no changes in phospholipid level were observed during frozen storage. The results suggest that enzymatic hydrolysis of neutral lipids plays a major role in the sensory deterioration of salmon during frozen storage.
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Hansen PB, Jensen BL, Andreasen D, Friis UG, Skøtt O. Vascular smooth muscle cells express the alpha(1A) subunit of a P-/Q-type voltage-dependent Ca(2+)Channel, and It is functionally important in renal afferent arterioles. Circ Res 2000; 87:896-902. [PMID: 11073885 DOI: 10.1161/01.res.87.10.896] [Citation(s) in RCA: 64] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
In the present study, we tested whether the alpha(1A) subunit, which encodes a neuronal isoform of voltage-dependent Ca(2+) channels (VDCCs) (P-/Q-type), was present and functional in vascular smooth muscle and renal resistance vessels. By reverse transcription-polymerase chain reaction and Southern blotting analysis, mRNA encoding the alpha(1A) subunit was detected in microdissected rat preglomerular vessels and vasa recta, in cultures of rat preglomerular vascular smooth muscle cells (VSMCs), and in cultured rat mesangial cells. With immunoblots, alpha(1A) subunit protein was demonstrated in rat aorta, brain, aortic smooth muscle cells (A7r5), VSMCs, and mesangial cells. Immunolabeling with an anti-alpha(1A) antibody was positive in acid-macerated, microdissected preglomerular vessels and in A7r5 cells. Patch-clamp experiments on aortic A7r5 cells showed 22+/-4% (n=6) inhibition of inward Ca(2+) current by omega-Agatoxin IVA (10(-8) mol/L), which in this concentration is a specific inhibitor of P-type VDCCs. Measurements of intracellular Ca(2+) in afferent arterioles with fluorescence-imaging microscopy showed 32+/-9% (n=10) inhibition of the K(+)-induced rise in Ca(2+) in the presence of 10(-8) mol/L omega-Agatoxin IVA. In microperfused rabbit afferent arterioles, omega-Agatoxin IVA inhibited depolarization-mediated contraction with an EC(50) of 10(-17) mol/L and complete blockade at 10(-14) mol/L. We conclude that the alpha(1A) subunit is expressed in VSMCs from renal preglomerular resistance vessels and aorta, as well as mesangial cells, and that P-type VDCCs contribute to Ca(2+) influx in aortic and renal VSMCs and are involved in depolarization-mediated contraction in renal afferent arterioles.
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MESH Headings
- Animals
- Arterioles/cytology
- Arterioles/metabolism
- Blotting, Western
- Calcium/metabolism
- Calcium Channel Blockers/pharmacology
- Calcium Channels, P-Type/biosynthesis
- Calcium Channels, P-Type/genetics
- Calcium Channels, Q-Type/biosynthesis
- Calcium Channels, Q-Type/genetics
- Cells, Cultured
- In Vitro Techniques
- Ion Transport/drug effects
- Kidney/blood supply
- Kidney/cytology
- Muscle, Smooth, Vascular/cytology
- Muscle, Smooth, Vascular/metabolism
- Patch-Clamp Techniques
- Perfusion
- Protein Subunits
- Rabbits
- Rats
- Sequence Analysis, DNA
- Vascular Resistance/genetics
- omega-Agatoxin IVA/pharmacology
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