Atrial natriuretic factor reduces vasopressin and angiotensin II but not the ACTH response to acute hypoglycaemic stress in normal men.
OBJECTIVE
We determined the effects of physiological (non-hypotensive) increments of plasma atrial natriuretic factor (ANF) on the vasopressin and hypothalamic-pituitary-adrenal response to insulin induced hypoglycaemia.


METHODS
Single blind, placebo controlled, randomized study of the effect of vehicle alone or ANF (2.5 pmol/kg/min for 120 minutes) commencing 30 minutes before bolus administration of insulin (0.15 U/kg body weight).


RESULTS
ANF infusion raised venous plasma ANF levels four to five-fold (mean level 32 +/- 0.3 pmol/l at time of insulin injection) without affecting resting blood pressure or heart rate. After insulin, the fall in plasma glucose and rise in plasma adrenaline and noradrenaline were similar in both studies. In contrast, the responses in plasma arginine vasopressin (P < 0.02) and in plasma angiotensin II (P < 0.05) were inhibited by ANF. Plasma corticotrophin releasing factor, ACTH and cortisol responses to hypoglycaemic stress did not differ significantly in the presence and absence of ANF.


CONCLUSIONS
We conclude that four to five-fold acute increase in plasma ANF, while attenuating vasopressin and angiotensin II responses to hypoglycaemia, does not inhibit the hypothalamic, pituitary and adrenal responses or inhibit sympathetic nervous activation in normal men.
Department of Endocrinology, Christchurch Hospital, New Zealand.
G A
GA
Wittert
E A
EA
Espiner
A M
AM
Richards
R A
RA
Donald
J H
JH
Livesey
T G
TG
Yandle
D000208:Acute Disease; D000324:Adrenocorticotropic Hormone / Q000097:blood*; D000328:Adult; D000804:Angiotensin II / Q000097:blood*; D001127:Arginine Vasopressin / Q000097:blood*; D009320:Atrial Natriuretic Factor / Q000097:blood / Q000494:pharmacology*; D003346:Corticotropin-Releasing Hormone / Q000097:blood; D006801:Humans; D007003:Hypoglycemia / Q000097:blood* / Q000139:chemically induced / Q000503:physiopathology; D007030:Hypothalamo-Hypophyseal System / Q000187:drug effects / Q000503:physiopathology; D007328:Insulin / Q000494:pharmacology; D008297:Male; D010913:Pituitary-Adrenal System / Q000187:drug effects / Q000503:physiopathology; D016037:Single-Blind Method
D007328:Insulin; D000804:Angiotensin II; D001127:Arginine Vasopressin; D009320:Atrial Natriuretic Factor; D000324:Adrenocorticotropic Hormone; D003346:Corticotropin-Releasing Hormone