Studies on functional difference of blood vessels and sympathetic nerve mechanisms of them

点击翻译按钮获取中文摘要

In this project, the characteristics of the blood vessels and specificity of sympathetic nerve innervated them were studied. 1. There were differences on catecholamine contents among the blood vessels. 2. Correlation between endogenous catecholamine contents and uptake of exogenous catecholamines in each vessel was observed. 3. High level of dopamine in the rabbit pulmonary artery was found. Uptake of exogenous dopamine and release of it from nerve endings were shown. These results suggested possible dopaminergic innervation in the artery. 4. High level of adrenaline in rabbit abdominal aorta and inferior vena cava was found and the presence of adrenaline synthetase in the vessels was shown. 5. High level of adrenaline in the renal artery and vein was found and it was considered as uptake of it from blood stream. 6.Effects of vasoactive peptides such as atrial natriuretic peptide (ANP) and urotensin I (UI) on blood vessels were studied. (1) Renal artery was the most sensitive to ANP and vasodilatory effects of ANP was suggested to be mediated through the inhibition of calcium coupling contractile mechanism in the smooth muscle cells. (2) Mesenteric artery was the most sensitive to UI. Reduction of vasodilatory effect of UI in the spontaneously hypertensive rats with the development of hypertension was observed and the reduction was considered to be mediated through the stimulation of endogenous prostaglandins synthesis. Vasodilatory effect of UI was suggested to be mediated through the inhibition of calcium entry into the smooth muscle cells. 7. Effects of aging on the drug responses in the rat blood vessels were studied. Furthermore, changes with aging were studied with special reference to water and salt metabolism. 8. Reduction of the response of the blood vessels to noradrenaline by one week treatment of nicotine was observed.