Cycloheximide prevents production of arresting, a fraction of 30-50 kDa obtained from seminiferous tubule conditioned medium.
OBJECTIVE
To evaluate the effect of a protein synthesis inhibitor cycloheximide on arresting activity in spermatogenesis and sperm count in male rats.


METHODS
The study used seminiferous tubule (ST) segments from adult rats cultured in vitro with or without cycloheximide to condition culture media, which have been concentrated, size fractioned (30-50 kDa) and administered 7 days to adult rats by intraperitoneal injections. The effects on testicular and epididymal weights, spermatogenesis and epididymal sperm count were determined.


RESULTS
The fraction (30-50 kDa), named arresting, obtained from the culture without cycloheximide decreased testicular and epididymal weights (P<0.01) and reduced the epididymal sperm count significantly. Study of the spermatogenic cycle by transillumination showed spermatogenic arrest at stage VII in rats treated with arresting compared to that observed in controls. The length of stage VII in the group receiving the seminiferous tubules culture media with cycloheximide (30-50 KDa CHX-STCM fraction) was similar to control.


CONCLUSIONS
The difference in the effect may be the result of the presence or absence of arresting, a protein secreted by the tubules.
Gonzales
Gustavo F
GF
Instituto de Investigaciones de la Altura, Universidad Peruana Cayetano Heredia, Lima, Peru. iiad@upch.edu.pe.
Hartinger
Stella
S
Flores
Yetssy
Y
Zarate
Kelly
K
Yi
Pedro
P
D000818:Animals; D019393:Arrestin / Q000096:biosynthesis*; D017077:Culture Media, Conditioned; D003513:Cycloheximide / Q000494:pharmacology*; D004822:Epididymis / Q000166:cytology / Q000187:drug effects / Q000254:growth & development; D008297:Male; D011500:Protein Synthesis Inhibitors / Q000494:pharmacology*; D051381:Rats; D012670:Seminiferous Epithelium / Q000166:cytology / Q000187:drug effects / Q000502:physiology; D012671:Seminiferous Tubules / Q000378:metabolism*; D013076:Sperm Count; D013737:Testis / Q000187:drug effects / Q000254:growth & development
D019393:Arrestin; D017077:Culture Media, Conditioned; D011500:Protein Synthesis Inhibitors; D003513:Cycloheximide