Specificity in mineralocorticoid versus glucocorticoid action.

The mineralocorticoid receptor (MR) and the glucocorticoid receptor (GR) share considerable structural and functional homology. Overlapping effects on epithelial sodium transport are observed in vivo; in vitro, both are able to bind and transactivate through a common hormone response element. This has led several investigators to suggest that specificity is conferred primarily by prereceptor mechanisms, and we have addressed this question using both in vitro and in vivo approaches.

Intracellular signaling pathways confer specificity of transactivation by mineralocorticoid and glucocorticoid receptors.

The glucocorticoid receptor (GR) and the mineralocorticoid receptor (MR) bind similar ligands and target genes in vitro yet have distinct roles in vivo. With a single exception, known mechanisms conferring specificity have been limited to prereceptor mechanisms. These alone cannot account for specificity, particularly at a transcriptional level.

The Australian Multicenter Trial of Growth Hormone (GH) Treatment in GH-Deficient Adults.

GH treatment in adults with GH deficiency has numerous beneficial effects, but most studies have been small. We report the results of an Australian multicenter, randomized, double-blind, placebo-controlled trial of the effects of recombinant human GH treatment in adults with GH deficiency. GH deficiency was defined as a peak serum GH of < 5 mU/liter in response to insulin-induced hypoglycemia.

Differential expression of nuclear 11beta-hydroxysteroid dehydrogenase type 2 in mineralocorticoid receptor positive and negative tissues.

Corticosteroid hormone action is controlled at a pre-receptor level by the activity of two isoforms of 11beta-hydroxysteroid dehydrogenase (11beta-HSD), catalyzing the interconversion of hormonally active cortisol to inactive cortisone. In particular 11beta-HSD2 protects the mineralocorticoid receptor (MR) from glucocorticoid excess, enabling aldosterone to interact with the MR. We have analyzed the subcellular localization of 11beta-HSD2 in relation to the expression of the MR in human colon and placenta.

Determinants of specificity of transactivation by the mineralocorticoid or glucocorticoid receptor.

Glucocorticoids and mineralocorticoids have distinct in vivo roles despite close structural homology and similarities in vitro. Known mechanisms of specificity focus on factors extrinsic to the receptor; interactions that directly regulate the receptor to confer specificity are less well understood, particularly for the mineralocorticoid receptor (MR). To examine relative MR vs.