.alpha. Adrenergic agonist (noradrenaline [norepinephrine, NE] 2, 20 and 200 .mu.g) and antagonist (phenoxybenzamine, 15 mg), and .beta. adrenergic agonist (isoproterenol, 2, 20 and 200 .mu.g) and antagonist (propranolol, 6 mg) were tested on isolated perfused canine pancreas under basal conditions and under stimulation by secretin (0.5 clinical unit/h) or cerulein (600-1200 ng/h). NE induced a strong vasoconstriction (inhibited by phenoxybenzamine) followed by a moderate vasodilation (possibly mechanical). NE did not stimulate a resting pancreas and inhibited a pancreas from secreting in response to secretin or cerulein. After phenoxybenzamine, in the absence of vasoconstriction, this latter effect was reversed into a dose-dependent stimulation of hydrelatic secretion, suggesting that NE had a direct action on the secretory cell. There was no stimulation of protein and no acinar degranulation. Propranolol and atropine did not modify effectiveness of NE. Isoprenaline had a weak vasodilatory effect but no effect on secretion. Adrenergic blocking agents did not alter response to secretin or cerulein.