Effects of growth hormone replacement on cortisol metabolism in hypopituitary patients treated with cortisone acetate

11beta-hydroxysteroid dehydrogenase activity in acromegalic patients with normal or impaired carbohydrate metabolism

The 11beta-hydroxysteroid dehydrogenase isoenzymes (11beta-HSD) catalyse the interconversion of cortisol (F) and cortisone (E). Earlier studies demonstrated that growth hormone (GH) and insulin resistance may exert opposite effects on the conversion of E to F by 11beta-HSD type 1. Therefore, in the present study we determined F and E concentrations in 562 plasma samples obtained from acromegalic patients during an active phase (76 patients) and after cure of the disease (68 patients). In addition, we examined whether type 2 diabetes mellitus or impaired glucose tolerance, which are frequently associated with active acromegaly could influence plasma F and E levels in these patients. We found that plasma F concentrations were similar in patients with active acromegaly and in those who were cured with pituitary surgery, irradiation and/or medical therapy (mean+/-S.E., 12.4+/-0.3 and 12.7+/-0.4 microg/dl, respectively). However, plasma E levels were significantly higher in patients with active compared to those with cured acromegaly (2.8+/-0.1 and 2.2+/-0.1 microg/dl, respectively; p<0.001), resulting in a lower F/E ratio in patients with active disease (4.6+/-0.1 vs. 5.9+/-0.2 in the cured group of patients; p<0.001). When the effect of altered carbohydrate homeostasis on plasma F and E was analysed, the results indicated significantly lower plasma E levels and higher F/E ratios in active acromegalic patients with type 2 diabetes mellitus or impaired glucose tolerance compared to those with normal carbohydrate metabolism (E, 2.5+/-0.1 and 3.0+/-0.1 microg/dl, respectively; F/E, 5.1+/-0.2 and 4.4+/-0.1; p<0.001), whereas plasma F concentrations were similar in these two groups (12.1+/-0.4 and 12.6+/-0.3 microg/dl, respectively). These findings indicate that disease activity exerts a significant impact on 11beta-HSD in acromegalic patients, which is further modified with altered carbohydrate homeostasis, frequently present in patients with active disease.

Anterior pituitary hormone replacement therapy--a clinical review

This clinical review summarizes current approaches to diagnosis and treatment of anterior pituitary hormone deficiency. The diagnostic value of endocrine function tests and replacement strategies for hydrocortisone, thyroxine, sex steroids, and growth hormone replacement are reviewed. Female androgen deficiency syndrome and the current role of DHEA and testosterone replacement in women are also discussed.