Journal of anesthesia
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Journal of anesthesia · Jan 2003
Effects of ketamine on neostigmine-induced contractile and phosphatidylinositol responses of the rat trachea.
Neostigmine causes airway smooth muscle contraction through the direct stimulation of muscarinic receptors and the activation of phosphatidylinositol (PI) responses. Ketamine attenuates airway smooth muscle contraction. It is not clear whether ketamine attenuates neostigmine-induced airway smooth muscle contraction by inhibiting the PI response. This study was designed to examine the effects of ketamine on neostigmine-induced contractile and PI responses of the rat trachea. ⋯ The results suggest that ketamine attenuates neostigmine-induced contractile responses, at least in part, through the inhibition of phospholipase C coupled with G protein in the PI response.
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Journal of anesthesia · Jan 2003
Effects of halothane and isoflurane on acetylcholine-induced, endothelium-dependent vasodilation in perfused rat mesenteric arterial beds.
The present study was designed to examine the effects of halothane and isoflurane on acetylcholine-induced, endothelium-dependent vasodilation in rat mesenteric arterial beds perfused at a constant flow both in vitro and in situ. ⋯ These results suggest that, in resistance arteries in conditions of constant flow, halothane and isoflurane do not affect vasodilations in response to an endothelium-dependent agonist. However, in these preparations, once the enzymatic activity of nitric oxide synthase is inhibited, higher concentrations of halothane, but neither isoflurane nor the lower concentration of halothane, appear to impair endothelium-dependent relaxations, probably mediated by TEA-sensitive K+ channels.