Document Detail

Spermatogonial apoptosis has three morphologically recognizable phases and shows no circadian rhythm during normal spermatogenesis in the rat.
MedLine Citation:
PMID:  1596537     Owner:  NLM     Status:  MEDLINE    
In this study we examined the possibility that regular or circadian fluctuations occur in the frequency of spontaneous spermatogonial apoptosis. Apoptosis of A2, A3 and A4 type spermatogonia occurring spontaneously in the normal rat testis was studied by light and electron microscopy. Normal and apoptotic A3 spermatogonia were quantified in 36 animals killed at two-hourly intervals over a 24 h period. Three sequential phases of spermatogonial apoptosis were defined and quantified separately: (i) an early phase in which cells showed margination of nuclear chromatin, (ii) an intermediate phase in which phagocytosed apoptotic bodies were partly degraded and (iii) a late phase in which only debris of degraded apoptotic bodies was evident. Groups of spermatogonia linked by intercellular bridges underwent apoptosis synchronously. Normal and apoptotic A3 spermatogonia occurred at a mean frequency of 33.4 and 9.6 per 10 seminiferous tubule profiles respectively; there was a large variation in these frequencies between animals, but no peaks or circadian periodicity were detected. Progressive degradation of apoptotic bodies was evident, the average ratios of intermediate and late bodies to early bodies being 1.5 and 3.5, respectively. Absence of a circadian rhythm in these data does not exclude the possibility that initiation of apoptosis in susceptible spermatogonial clones is synchronous, and that affected clones undergo lag periods of differing duration before expressing morphological apoptosis.
D J Allan; B V Harmon; S A Roberts
Related Documents :
7889527 - Induction of apoptotic cell dna fragmentation in human cells after treatment with hyper...
12210057 - In vitro model for the study of necrosis and apoptosis in native cartilage.
14615277 - Hexarelin protects rat cardiomyocytes from angiotensin ii-induced apoptosis in vitro.
15993557 - Apoptosis and nitric oxide in an experimental model of osteoarthritis in rabbit after h...
21477797 - Thalidomide inhibits interferon-γ-mediated nitric oxide production in mouse vascular en...
22665947 - Epigenetic regulation of cytokine production in human amnion and villous placenta.
Publication Detail:
Type:  Journal Article; Research Support, Non-U.S. Gov't    
Journal Detail:
Title:  Cell proliferation     Volume:  25     ISSN:  0960-7722     ISO Abbreviation:  Cell Prolif.     Publication Date:  1992 May 
Date Detail:
Created Date:  1992-07-08     Completed Date:  1992-07-08     Revised Date:  2006-11-15    
Medline Journal Info:
Nlm Unique ID:  9105195     Medline TA:  Cell Prolif     Country:  ENGLAND    
Other Details:
Languages:  eng     Pagination:  241-50     Citation Subset:  IM    
Centre for Molecular Biotechnology, Queensland University of Technology, Brisbane, Australia.
Export Citation:
APA/MLA Format     Download EndNote     Download BibTex
MeSH Terms
Cell Death
Circadian Rhythm
Rats, Inbred Strains
Spermatogonia / cytology*

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine

Previous Document:  Kinetics of the calcium induced stratification of human keratinocytes in vitro.
Next Document:  G1 shortening following unbalanced growth: a specific v. nonspecific effect.