Increase of XXXX -induced endothelium-dependent relaxation of @entity358 in @entity35 after chronic exposure to cold.

@entity2472 @entity358 @entity2647 @entity35 @entity1063 @entity934
The present study was designed to determine whether @entity1063 (NE) mediate endothelium-dependent relaxations in arteries of the pulmonary vasculature of cold-acclimated @entity35 . Twenty male @entity35 comprising two groups (Cold-acclimated for 12 weeks at 6  C, CA; Warm-acclimated for 12 weeks at 24   C, WA) were used. After anesthesia, the @entity358 (4 mm long) was isolated. Pulmonary artery with and without endothelium were suspended for isometric force measurements in a buffered salt solution. The doseresponse relations for the vascular responses to the isolated @entity358 to @entity1063 (NE), @entity2647 (PE) and @entity934 (Ach) were determined and compared in the CA group and the WA group. In the CA group, the vascular sensitivities to NE and PE-induced @entity2472 in the @entity358 was significantly lowered than that in the WA group. NE and PE-induced contractions were significandy greater in endotheliumdenuded compared with endothelium-intact arteries. These differences of @entity2472 responses to NE and PE between arteries with widiout endothelium were significantly greater in the CA group than in the WA group. There was no significant difference between the pulmonary arterial response to Ach in the CA group and that in the WA group. Our data suggest that chronic exposure to cold show decreased NE and PE-induced @entity2472 responses in isolated pulmonary arteries and may decrease NE-induced @entity2472 responses due to enhancing NE-induced endodielium derived relaxing factor release via up-regulating endothelial a-adrenoceptors.
