<Originals>Alpha-1 adrenergic function in hemodynamic control of stroke-prone spontaneously hypertensive rats (SHRSP)

概要

論文の詳細を見る
At the initial stage of hypertension in spontaneously hypertensive rat (SHR) strains, hyperactivity in the sympathetic nervous system, an increase of norepinephrine release into the blood, decreases of norepinephrine and dopamine contents in the brain stem, hyperresponses to α_1-adrenergic agents in the aorta, femoral artery, and portal vein were reported. To elucidate the mechanisms to develop hypertension, α_1-adrenergic vasocontractile function in SHR strains was parformed by a radiolabeled microsphere method on the stimulation of α_1-agonist, methoxamine, or inhibition by α_1-blocker, bunazosin, in 6-month-old SHRSP. The results were as follows. 1) There was no difference in the response of the central and peripheral hemodynamics to α_1-agonist, methoxamine, and in the activities of the intrinsic α_1-adrenergic system estimated by the administration of bunazosin between SHRSP and normotensive Wistar Kyoto rats (WKY). 2) Blood pressure elevated by α_1-agonist largely contributed to the increase of brain blood flow. 3) Lower circulation in the brain of SHRSP than in WKY was observed. 4) The effect of α_1-agonist such as methoxamine on the kidney, gastrointestinal tract, spleen, muscle, and skin of SHRSP was insignificant. The above suggests that intrinsic α_1-agonistsuch as norepinephrine in the peripheral tissues was not a main factor for the cause or continuance of hypertension in 6-month-old SHRSP.
近畿大学の論文