title: Study using in-vivo binding of 125I-labelled hCG, light and electron microscopy of the repopulation of rat Leydig cells after destruction due to administration of ethylene-1,2-dimethanesulphonate.
abstract: Gonadotrophin binding to rat Leydig cells after a single administration of ethylene dimethanesulphonate (EDS) (75 mg/kg i.p.) was followed by using intratesticular microdoses of 125I-labelled hCG, whilst corresponding morphological changes in the testicular interstitium were studied with light and electron microscopy. No discernible effect on 125I-labelled hCG binding compared with controls was observed until 24 h after treatment. Between 24 and 32 h a sharp decline in binding occurred which was correlated with extensive Leydig cell destruction. By 48 h the 125I-labelled hCG binding was negligible and no morphologically recognizable Leydig cells were found at this time. The specific binding remained low until 21 days after treatment and then a marked increase occurred to give nearly normal levels by 49 days. This was consistent with a generalized repopulation of the interstitium with Leydig cells, seemingly the result of differentiation of fibroblast-like precursor cells.
mesh_terms: D000818:Animals; D002454:Cell Differentiation; D006063:Chorionic Gonadotropin / Q000378:metabolism; D007457:Iodine Radioisotopes; D007985:Leydig Cells / Q000187:drug effects* / Q000378:metabolism / Q000648:ultrastructure; D008297:Male; D008698:Mesylates / Q000494:pharmacology*; D008854:Microscopy, Electron; D011485:Protein Binding; D051381:Rats; D011919:Rats, Inbred Strains; D013997:Time Factors
chemical_list: D006063:Chorionic Gonadotropin; D007457:Iodine Radioisotopes; D008698:Mesylates; C002994:ethylene dimethanesulfonate