Abstract
We examined that effects of thymoxamine hydrochloride (thymoxamine) on the peripheral blood vesseles, in particular cerebral circulation and cerebral metabolic function, in vitroandin vivostudies.
1) Thymoxamine was more effective in antagonizing methoxamine than clonidine-induced contractile responses in dog basiler arteries.
2) Vasodilating actions of thymoxamine were greater in basiler artery than in mesentric and femoral arteries of dogs.
3) The blood vesseles of ear were markedly vasodilated by oral administration of 120mg/ kg/day of thymoxamine, with rise of skin temperature of ear in the rabbits.
4) Pial arteries of cerebral in cats, vasodilating effects of thymoxamine (0.03-3.0mg/kg i.v.) were greater in thin blood vesseles than in thick blood vesseles.
5) Thymoxamine (0.1-3.0 mg/kg i.v.) increased dose-dependently not only the basiler artery blood flow but also the internal carotid artery blood flow in an anesthesic cats.
6) The regional blood flow of hippocampal and amygdala in cat brain were significantly increased by treated with thyoxmamine (0.03-3.0 mg/kg i.v.) and cerebral cortical and hypothalamic blood flows showed tend to increase.
7) Lowering of mitochondrial respiratory control due to the ligation of bilateral carotid arteries of spontaneously hypertensive rats showed tend to improve with treatment with thymoxamine.
These results seems to support that the clinical usefulness of thymoxamine in the patients with cerebrovascular disorders.
