Dose and time relationships in the endocrine response of the irradiated adult rat testis.
The dose- and time-dependent responses for the interstitial and tubular compartments in irradiated adult rat testes are described. Leydig cell dysfunction, as indicated by increased serum LH (to a maximum of 385% of control after 5 Gy) and decreased serum T (to a minimum of 30% of control after 10 Gy), was observed at 8 weeks postirradiation. Subsequent recovery of Leydig cell function was then observed, so that after 9 months serum T was normal but LH was still marginally elevated. The dysfunction, with a threshold of about 4 to 5 Gy, was associated with a loss of Leydig cells from the testis. Spermatogenic damage was observed; after doses of 3 Gy and above a marked dose-response was recorded as assessed by counts of tubule cross sections exhibiting spermatogenesis. Reduced serum levels of androgen binding protein indicated Sertoli cell dysfunction at 8 weeks after 3 Gy and above, with values of less than one half of those seen in the controls. Serum FSH also was elevated to between 150% and 200% of control, and after 9 months closely reflected androgen binding protein changes. Unlike the Leydig cell, no recovery with time was observed for this aspect of Sertoli cell function.
D000727:Androgen-Binding Protein / Q000097:blood; D000818:Animals; D004307:Dose-Response Relationship, Radiation; D005640:Follicle Stimulating Hormone / Q000097:blood*; D007700:Kinetics; D007985:Leydig Cells / Q000502:physiology; D007986:Luteinizing Hormone / Q000097:blood*; D008297:Male; D009929:Organ Size; D011832:Radiation Injuries / Q000473:pathology / Q000503:physiopathology*; D051381:Rats; D011919:Rats, Inbred Strains; D011956:Receptors, Cell Surface / Q000378:metabolism; D011974:Receptors, LH; D012038:Regeneration; D012671:Seminiferous Tubules / Q000503:physiopathology; D013733:Testicular Diseases / Q000209:etiology* / Q000473:pathology / Q000503:physiopathology; D013739:Testosterone / Q000097:blood*
D000727:Androgen-Binding Protein; D011956:Receptors, Cell Surface; D011974:Receptors, LH; D013739:Testosterone; D007986:Luteinizing Hormone; D005640:Follicle Stimulating Hormone