AJP - Gastrointestinal and Liver Physiology, Vol 241, Issue 4 321-G327, Copyright © 1981 by American Physiological Society
Pyloric pressure response to insulin-induced hypoglycemia in humans
K. Phaosawasdi, R. Goppold and R. S. Fisher
The pyloric pressure response to insulin-induced hypoglycemia was studied.
Studies were performed in 102 experiments on 38 normal subjects. During
insulin-induced hypoglycemia, pyloric pressure increased from 5.5 +/- 1.2
to 10.8 +/- 1.1 mmHg (P less than 0.02). This increase in pyloric pressure
ws not due to a direct effect of insulin, duodenal acidification, or the
release of corticosteroids or growth hormone. Glucagon doses of 2 and 5
micrograms . kg-1 . h-1 increased pyloric pressure from 4.7 +/- 1.1 to 6.7
+/- 0.5 mmHg (P less than 0.05) and from 4.7 +/- 1.1 to 8.5 +/- 1.1 mmHg (P
less than 0.02), respectively. Pyloric pressures were increased to 10.8 +/-
0.9 (P less than 0.01) and 13.0 +/- 1.4 mmHg (P less than 0.01) at 0.1 and
0.2 micrograms . kg-1 . min-1 of epinephrine, respectively. Neither
cholinergic blockade nor alpha-adrenergic blockade significantly affected
the pyloric pressure response to insulin hypoglycemia. beta-Adrenergic
blockade abolished the pyloric pressure responses to both insulin
hypoglycemia and epinephrine. Neither beta- nor alpha-adrenergic
stimulation altered the basal pyloric pressure. In contrast, the
combination of isoproterenol and phenylephrine increased the pyloric
pressure significantly from 4.2 +/- 0.8 to 12.0 +/- 1.7 mmHg ( P less than
0.01). These observations suggest that insulin hypoglycemia increases
pyloric pressure by an adrenergic mechanism that requires stimulation of
both alpha- and beta-receptors.
