Effects of isoflurane and sevoflurane anesthesia on arteriovenous shunt flow in the lower limb of diabetic patients without autonomic neuropathy.

Background: Failure of sympathetic nerve control caused by diabetic neuropathy results in vasodilation of arteriovenous shunts. The aim of this study was to test the hypothesis that the function of arteriovenous anastomoses was disordered in mild diabetic patients without apparent neuropathy, and that volatile anesthetics opened arteriovenous shunts more greatly in nondiabetic patients than diabetic patients.

Methods: Autonomic system function was assessed by cardiovascular reflex tests.

Augmented activity of adenosine triphosphate-sensitive K+ channels induced by droperidol in the rat aorta.

Droperidol produces the inhibition of K+ channels in cardiac myocytes. However, the effects of droperidol on K+ channels have not been studied in blood vessels. Therefore, we designed the present study to determine whether droperidol modulates the activity of adenosine triphosphate (ATP)-sensitive K+ channels in vascular smooth muscle cells.

Sevoflurane enhances nitroglycerin tolerance in rat aorta: implications for the desensitization of soluble guanylate cyclase possibly through the additive generation of superoxide anions and/or hydroxyl radicals within vascular smooth muscle.

Unlabelled: Nitroglycerin (TNG) tolerance, defined as an impaired vasodilation response to TNG, has been recently demonstrated to be associated with increased production of reactive species. We designed this study to investigate the mechanisms that mediate TNG tolerance and to compare the effects of sevoflurane and isoflurane on the development of TNG tolerance. Tension changes in rat aortic rings without endothelium were recorded.

The inhibitory effects of isoflurane on protein tyrosine phosphorylation-modulated contraction of rat aortic smooth muscle.

Background: Tyrosine kinase-catalyzed protein tyrosine phosphorylation plays an important role in initiating and modulating vascular smooth muscle contraction. The aim of the current study was to examine the effects of isoflurane on sodium orthovanadate (Na3VO4), a potent protein tyrosine phosphatase inhibitor-induced, tyrosine phosphorylation-mediated contraction of rat aortic smooth muscle.

Methods: The Na3VO4-induced contraction of rat aortic smooth muscle and tyrosine phosphorylation of proteins including phospholipase Cgamma-1 (PLCgamma-1) and p44/p42 mitogen-activated protein kinase (MAPK) were assessed in the presence of different concentrations of isoflurane, using isometric force measurement and Western blotting methods, respectively.