Beta endorphin selectively stimulates aldosterone secretion in hypophysectomized, nephrectomized dogs.

Abstract

A B S T R A C T We examined the effects of synthetic human /-endorphin (BEND) and a stable methionine (Met)-enkephalin analogue on aldosterone and cortisol secretion rates in anesthetized, hypophysectomized, and nephrectomized dogs and compared them to those of (1-39) ACTH. The circulation of the adrenal glands was completely isolated on the arterial and venous sides (Hilton Pouch). The peptides were infused to deliver 3 pmol/min into the aortic "pouch." Blood was collected from the vena caval pouch, which received blood only from the adrenal gland. Secretion rates of aldosterone and cortisol were calculated as the product of adrenal blood flow and venous steroid concentration. Duplicate steroid measurements were obtained during a control period, at 10, 30, and 50 min of peptide infusion and during a postcontrol period. BEND increased aldosterone secretion rate from 2.4±0.5 ng/ min (mean±SEM) to 3.2±0.9 ng/min at 10 min (N.S.), 8.2±2.5 ng/min (P < 0.05) at 30 min and 11.0±3.7 ng/ min (P < 0.05) at 50 min of infusion. Cortisol secretion rate was not affected by infusion of SEND. Infusion of the stable Met-enkephalin analogue D-alanine2; Metphenylalanine4, Met(O)-enkephalin-ol or saline alone had no effect on aldosterone or cortisol secretion rates. ACTH infusion increased mean aldosterone secretion rate by -215% and significantly stimulated cortisol secretion rate. These results indicate that BEND selectively stimulates aldosterone secretion with a potency similar to that of an equimolar dose of ACTH. INTRODUCTION There is considerable indirect evidence suggesting that an unidentified pituitary factor other than ACTH

Inappropriate Elevation of the Aldosterone/Plasma Renin Activity Ratio in Hypertensive Patients with Increases of 11-Deoxycorticosterone and 18-Hydroxy-ll-Deoxycorticosterone: A Subtype of Essential Hypertension?

“…Although an increase in serum (3-lipotropin or p-endorphin can be responsible for inappropriate aldosterone se cretion [28,29], an elevation of serum 0-lipotropin and P-endorphin in patients of group 3a was not found. The presence of an aldosterone-stimulating factor distinct from ACTH might be responsible for our findings in patients of group 3a [30][31][32], The hypoth esis is compatible with adrenal [l3lI]-cholesterol accumulation in patients with hyper plastic adrenals in groups 2 and 3a after dexamethasone administration and larger adrenal size in patients of group 3a than in patients of group 4.…”

Effects of Opioid Peptides on Aldosterone Production: Stimulatory Effect of Leu-Enkephalin*

“…The question of whether endogenous opiates have a physiological role in modulating aldosterone secretion is still unsolved. The latter has been reported either to be ineffective or to stimulate aldosterone production (4,5). 0-Lipotropin is a precursor of both jSMSH and the opioid peptide /3-endorphin.…”

Opioid peptides do not modulate atrial natriuretic peptide or aldosterone release under basal conditions in man

“…al. 1982), while in isolated dog adrenals, ß-endorphin, but not DAMME, was stimulatory (Gullner & Gill, 1983). In man, the synthetic opiate-like peptide dermorphin stimulated both plasma renin and aldosterone release, although the latter change was not statistically signifi¬ cant (Degli Uberti, Trasforini, Salvadori et al 1983).…”