Effect of atracurium, vecuronium, pancuronium and tubocurarine on renal sympathetic nerve activity in baroreceptor denervated dogs

The mechanism of arterial hypotension induced by non-depolarizing neuromuscular blocking agents may be multifactorial and differ between drugs. The purpose of this study was to evaluate the effect of high-dose atracurium and equivalent doses of other non-depolarizing neuromuscular blocking agents on haemodynamic state and sympathetic nervous activity. In studies on 24 mongrel dogs anaesthetized with alpha-chloralose, the left kidney was exposed retroperitoneally and renal sympathetic nerve activity was recorded continuously after bilateral sino-aortic denervation and cervical vagi section. The dogs were allocated to four groups; atracurium 1.5 mg kg−1, tubocurarine 0.3 mg kg−1 pancuronium 0.3 mg kg−1 or vecuronium 0.3 mg kg−1 was administered to six dogs in each group. Histamine 1 μg kg−1 was given to two dogs in each group, 1 h before administration of neuromuscular blocking agents. We observed that atracurium and tubocurarine significantly decreased arterial pressure, heart rate and renal sympathetic nerve activity (P