Adrenal cortex — A newly recognized peripheral site of action of enkephalins

Effects of chronic administration of a methionine-enkephalin analogue on the zona glomerulosa of the rat adrenal cortex

“…However, other studies have reported neither acute effects [5] nor a notable inhibitory action of enkephalins [16] on isolated rat zona glomerulosa cells, but this discrepancy can be reasonably interpreted as due to the fact that differenct types and doses of enkephalins were employed. The notable decrease in the volume of the lipid droplet compartment may be easily explained by considering that in the lipid droplets are stored cholesterol and cholesterol esters [11,19], the main precursors in aldosterone synthesis [18].…”

“…Many lines of evidence suggest that some pro-opiomelanocortin-derived peptides are involved in the regulation of zona glomerulosa secretory activity: lipotropins [5,7,8,27], endorphins [3,15], a-melanotropin [4,5,21,[23][24][25], 13-melanotropin [5,8,9,29,30], and enkephalins [1,16]. However, studies on the effects of a long-term administration of these peptides on the growth and steroidogenic capacity of zona glomerulosa are completely lacking.…”

Morphological and functional studies of the paracrine interaction between cortex and medulla in the adrenal gland

“…1993; Heisler et al, 1989;Higuchi et al, 1986;Nawata et al, 1991;Rá cz et al, 1985;Rebuffat et al, 1988b), the calcitonin gene-related peptide (Mazzocchi et al, 1992a;Murakami et al, 1989), dynorphin , and somatostatin (Rebuffat et al, 1994). Enkephalins, produced in relevant amounts in the adrenal medulla, similarly influence the adrenal cortex (Rá cz et al, 1980). As these neuropeptides released by chromaffin cells obviously influence the steroidogenesis in the adrenal cortex in a paracrine interaction, we can assume that the basis of this interaction is formed by the extensive cellular contact zones between cortical and chromaffin cells found in mammals, including in humans.…”

Comparison of leucine enkephalin and adrenocorticotrophin effects on adrenal function in fetal and adult sheep

“…High concentrations of ß-endorphin stimulated corticosterone output from isolated rat adrenal cells, although with a potency less than 2% that of ACTH (Shanker & Sharma, 1979), whereas lower concentrations of ß-endorphin inhibited ACTH-stimulated or basal corticosterone output (Szalay & Stark, 1981). Racz et al (1980) reported that methionine-enkephalin and leucine-enkephalin suppressed corticosterone output by rat adrenal tissue in vitro.…”