Male gonadal function, prolactin secretion and lactotroph population in an experimental model of cirrhosis

Liver cirrhosis, a highly prevalent chronic disease, is frequently associated with endocrine dysfunctions, notably in the gonadal axis. We evaluated lactotroph population by immunohistochemistry, gonadotropins and prolactin by immunoradiometric assay and testosterone and estradiol by radioimmunoassay in adult male Wistar rats with cirrhosis induced by carbon tetrachloride. No significant difference in mean +/- SEM percentages of lactotrophs was found between cirrhotic animals and controls (N = 12, mean 18.95 +/- 1.29%). Although there was no significant difference between groups in mean serum levels of prolactin (control: 19.2 +/- 4 ng/mL), luteinizing hormone (control: 1.58 +/- 0.43 ng/mL), follicle-stimulating hormone (control: 19.11 +/- 2.28 ng/mL), estradiol (control: 14.65 +/- 3.22 pg/mL), and total testosterone (control: 138.41 +/- 20.07 ng/dL), 5 of the cirrhotic animals presented a hormonal profile consistent with hypogonadism, all of them pointing to a central origin of this dysfunction. Four of these animals presented high levels of estradiol and/or prolactin, with a significant correlation between these two hormones in both groups (r = 0.54; P = 0.013). It was possible to detect the presence of central hypogonadism in this model of cirrhotic animals. The hyperestrogenemia and hyperprolactinemia found in some hypogonadal animals suggest a role in the genesis of hypogonadism, and in the present study they were not associated with lactotroph hyperplasia.