|
|
||||||||
1 Division of Endocrinology, Department of Medicine
2 Division of Urology, Department of Surgery, Harbor-UCLA Medical Center and Los Angeles Biomedical Research Institute, David Geffen School of Medicine at UCLA, Torrance, California.
Address correspondence to Amiya P. Sinha Hikim, PhD, Division of Endocrinology, Box 446, Harbor-UCLA Medical Center, 1000 West Carson Street, Torrance, CA 90509. E-mail: hikim{at}gcrc.rei.edu
We examined, using young and old Brown-Norway rats, the involvement of the nitric oxide (NO)-mediated intrinsic pathway signaling in age-related activation of male germ-cell apoptosis. Increased apoptosis of germ cells was readily observed in the normal-looking testes of old rats. Testicular NO synthase (NOS) activity, assessed by measuring the synthesis of 3H-L-citrulline from 3H-L-arginine, and cytokine-inducible NO synthase (iNOS) levels, assessed by western blot assay, were increased significantly by 90% and 70%, respectively, in the old rats compared to that of young animals. Immunohistochemical analysis of age-related changes in the expression of iNOS in testes confirmed our findings based on western blot assay. Increased NO and germ-cell apoptosis during aging is further associated with cytosolic translocation of mitochondrial cytochrome c and poly (ADP) ribose polymerase (PARP) cleavage, thus, suggesting the involvement of NO-mediated intrinsic pathway signaling in age-related increase in germ-cell apoptosis in male Brown-Norway rats.
This article has been cited by other articles:
![]() |
Y. Jia, A. P. S. Hikim, Y.-H. Lue, R. S. Swerdloff, Y. Vera, X.-S. Zhang, Z.-Y. Hu, Y.-C. Li, Y.-X. Liu, and C. Wang Signaling Pathways for Germ Cell Death in Adult Cynomolgus Monkeys (Macaca fascicularis) Induced by Mild Testicular Hyperthermia and Exogenous Testosterone Treatment Biol Reprod, July 1, 2007; 77(1): 83 - 92. [Abstract] [Full Text] [PDF] |
||||
![]() |
B. A. Weissman, C. M. Sottas, P. Zhou, C. Iadecola, and M. P. Hardy Testosterone production in mice lacking inducible nitric oxide synthase expression is sensitive to restraint stress Am J Physiol Endocrinol Metab, February 1, 2007; 292(2): E615 - E620. [Abstract] [Full Text] [PDF] |
||||
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
|---|
| All GSA journals | The Gerontologist |
| Journals of Gerontology Series B: Psychological Sciences and Social Sciences | |