Sexually dependent changes in rat somatotropic cells following bilateral adrenalectomy

In order to elucidate the existence of gender-related variations in both growth hormone (GH) release and the activity of somatotropic cells following bilateral adrenalectomy, a morphometric analysis was performed on GH-immunoreactive cells from adult male and female rats after bilateral adrenalectomy, correlating the findings with the serum levels of the hormone. The results obtained were compared to those found in untreated animals. Bilateral adrenalectomy was seen to induce a decrease in serum GH levels (p less than 0.01) in male rats; this was accompanied by a significant decrease in cellular area (p less than 0.01), cytoplasmic area (p less than 0.05) and nuclear area (p less than 0.01) and by a decrease in the cytoplasmic immunoreaction intensity of GH cells. By contrast, the above-mentioned changes did not appear in the female rats. These results suggest that the action of glucocorticoids on the synthesis and release of GH depends on the sex of the animal.