The Effect of IlypoMerınia on Noradrenaline Phenylephrine and Serotonin-İnduced Contractions of Canine Saphenous Vein and Role of Calcium

Canin saphenous vein strips were suspended in an organ chambers filled with oxygenated physiological salt solution, and isometric contractions were alsa recorded. Noradrenaline, phenylephrine and serotonin caused dose-dependent contractions which were enhanced by cooling of medium from 37 to 25 C. Clonidine also caused contractions but, these responses weren't enhanced by cooling. Both the contractions induced by these agonists and their augmentations by cooling weren't inhibited by 10- M verapamil. When these procedure were repeated in the Ca2 -free solutions, the agonists-induced contractions were smaller than that of obtained in normal mediurn. However except clonidine-induced contractions, these responses were enhanced by cooling. These results were suggested that intracellular calciurn pools rnay play a functional role cooling-induced contractions of canine saphenous vein.