摘要:

SummaryThis study has compared the effect of withdrawal of testosterone (± replacement) with that of selective depletion of pachytene spermatocytes (PS) or round/elongating spermatids (RS), or both PS and RS, on the level of overall protein secretion by seminiferous tubules (ST) isolated at particular stage‐groups of the spermatogenic cycle. Testosterone withdrawal was induced by destroying the Leydig cells with a single injection of ethane‐dimethane sulphonate (EDS), with or without concomitant replacement of testosterone by injection; ST at stages II‐V, VI‐VIII or IX‐XII were then isolated from control and treated rats at 4 days after treatment. Methoxyaceticacid (MAA) was administered, in either one or two doses, to selectively destroy 80–100% of pachytene and later spermatocytes; ST at stages I‐V, VI‐VIII or IX‐XIV were then isolated at specific times after treatment such that ST were depleted selectively of either PS, RS or PS + RS. Isolated ST (5 cm) were then cultured for 22 h at 34°C with35S‐methionine and its incorporation into secreted proteins then quantified.Based on the incorporation of35S‐methionine, ST at stages VI‐VIII showed a significantly higher level of protein secretion than did ST at earlier or later stages. This difference was abolished following testosterone withdrawal but was maintained by testosterone replacement. The normal increase in protein secretion by ST at stages VI‐VIII was also prevented if either PS or RS were depleted, whereas depletion of either PS or RS alone had no significant effect on protein secretion by ST at stages I‐V, and only the depletion of RS significantly reduced protein secretion by ST at stages IX‐XIV. Depletion of both PS + RS reduced protein secretion significantly by ST at all stages. In contrast to the data for total protein secretion, the levels of sulphated glycoprotein (SGP)‐1 and SGP‐2 secreted by ST at stages VI‐VIII showed that these two Sertoli cell proteins were unaffected by germ cell depletion except after co‐depletion of PS + RS when secretion of SGP‐1 was halved. It is concluded that: (i) the increase in overall protein secretion by ST at stages VI‐VIII in the normal spermatogenic cycle is both androgen‐ and germ cell‐dependent: (ii) the modulatory effect of germ cells on ST‐protein secretion varies according to the stage of the spermatogenic cycle and the germ cell type and does not affect all secreted proteins: (iii) the changing germ cell complement is probably the trigger for the stage‐d

ISSN:0105-6263    

DOI:10.1111/j.1365-2605.1993.tb01155.x

出版商:Blackwell Publishing Ltd    

年代:1993

数据来源: WILEY

ISSN:0105-6263    

DOI:10.1111/j.1365-2605.1993.tb01156.x

出版商:Blackwell Publishing Ltd    

年代:1993

数据来源: WILEY

ISSN:0105-6263    

DOI:10.1111/j.1365-2605.1993.tb01157.x

出版商:Blackwell Publishing Ltd    

年代:1993

数据来源: WILEY