Mechanism of a Sympathomimetic Action of Propranolol in Dog

Effects of Propranolol on the Action of Neuromuscular Blocking Drugs

“…The effect of these appears to be related to its local anaesthetic action (Wislicki and Rosenblum, 1967) and is similar to the depression of contraction of skeletal muscle caused by quinidine (Wislicki, 1960). In contrast, the action of intravenous administration of smaller doses of propranolol may be due to its ability to release catecholamines (Kayaalp and Kiran, 1966) which in turn augment the release of acetylcholine (Krnjevic and Miledi, 1958) as indicated by acceleration by adrenaline of the discharge of miniature potentials and by the adrenaline-induced increase in the amplitude of endplate potentials in curarized rat muscle. Since the muscle response to depolarizing drugs resembles that to acetylcholine (Paton, 1951), an increased release of the latter at the neuromuscular junction after intravenous administration of propranolol would result, by a synergistic action, in an intensification of the neuromuscular blocking effect of decamethonium and suxamethonium.…”

“…After intra-arterial injection of comparatively large doses, propranolol, like the structurally related pronethalol (Tiirker and Kiran, 1965), augments the action of neuromuscular blocking agents (Wislicki and Rosenblum, 1967). It has been shown that propranolol not only blocks adrenergic beta-receptors but that it also has a sympathomimetic effect, apparently by inducing a release of catecholamines from the adrenal medulla (Kayaalp and Kiran, 1966). Since, under different conditions, sympathomimetic amines may antagonize or intensify the action of curarizing drugs (Bowman and Raper, 1966) we investigated whether smaller amounts of propranolol can modify the action of neuromuscular blocking substances.…”

PROCEEDINGS OF THE BRITISH PHARMACOLOGICAL SOCIETY: 5th‐6th JANUARY, 1970

“…The difference in the effect of piopranolol on the action of depolarizing and nondepolarizing blocking agents may be the result of a sympathomimetic action of the adrenaline f-receptor blocking agent because propranolol has been reported to release catecholamines (Kayaalp & Kiran, 1966) which in turn may augment the release of acetylcholine (Krnjevic & Miledi, 1958). An increased availability of transmitter at the neuromuscular junction during intravenous infusion of propranolol would result in an intensification of the blocking effect of depolarizing drugs but it would antagonize tubocurarine (1-utter & Loewenstein, 1955; Bowman, Goldberg & Raper, 1962).…”

Cortisol and epinephrine relationships associated with stress adaptation in swine

“…According to Kayaalp and Kiran (1966) Thus, a block would diminish heart rate, heart automaticity, and myocard ial contractility and may possibly induce bronchospasm. In the intestines, stimulation of both and ^ receptors inhibits smooth muscle contraction (Copeland, 1967).…”

“…However, propranolol given intra-arterial produced a sustained vasoconstriction in the perfused hind limb of the dog Kusakari (1965 and. Kayaalp and Kiran (1966) reported that propranolol induced a transient vasodilation by a sustained vasoconstriction in the denervated autoperfused hind limbs of dogs. These authors also found the «< adrenergic blocking agents, phentolamine and phenoxybenzamine, reduced or abolished the pressor response to propranolol.…”