Abstract
The effect of temperature on submaximal vasoconstrictions to an intraluminal injection of serotonin (5-HT) and methoxamine was investigated in isolated and perfused canine lingual and mesenteric arteries, using the cannula insertion method. In both arteries cooling (from 37°C to 27°C) caused a remarkable enhancement of vasoconstriction to 5-HT, but did not to methoxamine. In lingual arteries, methoxamine-induced constrictions were strongly depressed, although those were slightly depressed in mesenteric arteries. It is assumed that 5-HT produces an important role to modulate vascular tonicity in low temperature conditions.
