HETEROGENEITY OF GONADOTROPINS AND LEVELS OF UNCOMBINED LUTEINIZING-HORMONE SUBUNITS IN PITUITARIES OF CRYPTORCHID RAMS

Pituitaries were collected from intact rams and rams that had been ren dered bilaterally cryptorchid by surgery to examine the effects of cry ptorchidism on gonadotropin heterogeneity, levels of uncombined lutein izing hormone (LH) subunits, and the apparent molecular sizes of LH an d follicle-stimulating hormone (FSH). Cryptorchid rams had higher pitu itary contents of LH and FSH as well as reduced testicular weights. Th e levels of uncombined LH subunits, their apparent molecular weights, and the apparent molecular weights of intrapituitary LH were similar i n control and cryptorchid rams. However, the apparent molecular weight of intrapituitary FSH was slightly larger in cryptorchid rams. Crypto rchidism altered the pattern of gonadotropin heterogeneity by shifting the distribution of LH isoforms towards basic components and shifting the distribution of FSH isoforms towards acidic components. Thus, it appears that the altered gonadal feedback mechanisms resulting from cr yptorchidism modify the pattern of both LH and FSH heterogeneity by sh ifting the distribution of isoforms in opposite directions.