| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH |
|
|
|
|||||||
|
|||||||||
| ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
1 pharmacology, IIBR, Ness Ziona, Israel
2 cbr, population council, new york, New York, United States
3 Division of Neurobiology, Weill Medical College of Cornell University, New York, NY, United States Minor Outlying Islands
4 Neurology/Neurobiology, Weill Cornell Medical College, New York, New York, United States
5 Center for Biomedical Research, The Population Council, New York,, New York, United States; cbr, population council, new york, New York, United States
* To whom correspondence should be addressed. E-mail: baw{at}iibr.gov.il.
Immobilization stress (IMO) induces a rapid increase in glucocorticoid secretion (in rodents, corticosterone, CORT) and this is associated with decreased circulating testosterone (T) levels. Nitric oxide (NO), a reactive free radical and neurotransmitter, has been reported to be produced at higher rates in tissues such as brain during stress. The biosynthesis of T is also known to be dramatically suppressed by NO. Specifically, the inducible isoform of nitric oxide synthase (iNOS) was directly implicated in this suppression. In order to assess the respective roles of CORT and NO in stress mediated inhibition of T production, adult wild type (WT) and inducible nitric oxide synthase knockout male mice (iNOS -/-) were evaluated. Animals of each genotype were assigned to either basal control or 3 h IMO stress groups. Basal plasma and testicular T levels were equivalent in both genotypes whereas testicular weights of mutant mice were significantly higher compared to WT animals. Exposure to 3 h of IMO increased plasma CORT and decreased T concentrations in mice of both genotypes. Testicular T levels were also affected by stress in WT and mutant males, being sharply reduced in both genotypes. However, the concentrations of nitrite and nitrate, the stable metabolites of NO measured in testicular extracts did not differ between control and stressed WT and iNOS -/- mice. These results support the hypothesis that CORT, but not NO, is a plausible candidate to mediate rapid stress-induced suppression of Leydig cell steroidogenesis.
This article has been cited by other articles:
|
|
 |
|
  B. A. Weissman, C. M. Sottas, M. Holmes, P. Zhou, C. Iadecola, D. O. Hardy, R.-S. Ge, and M. P. Hardy Normal Responses to Restraint Stress in Mice Lacking the Gene for Neuronal Nitric Oxide Synthase J Androl, September 1, 2009; 30(5): 614 - 620. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
G.-X. Hu, H. Lin, C. M. Sottas, D. J. Morris, M. P. Hardy, and R.-S. Ge Inhibition of 11{beta}-Hydroxysteroid Dehydrogenase Enzymatic Activities by Glycyrrhetinic Acid In Vivo Supports Direct Glucocorticoid-Mediated Suppression of Steroidogenesis in Leydig Cells J Androl, May 1, 2008; 29(3): 345 - 351. [Abstract] [Full Text] [PDF]
|
|
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH |
| Visit Other APS Journals Online |
