EFFECTS OF INTRA-VENTRICULAR AND INTRA-SPINAL 6-HYDROXYDOPAMINE ON BLOOD-PRESSURE OF DOCA-SALINE HYPERTENSIVE RATS

  • 1 January 1979
    • journal article
    • research article
    • Vol. 238  (1) , 50-59
Abstract
The effects of intraventricular (brain) and intraspinal adminsitration of 6-hydroxydopamine (6-OH-DA) on the development and maintenance of DOCA[deoxycorticosterone acetate]-saline hypertension in rats were studied. Intraventricular administration of 6-OH-DA prevented the development of DOCA-saline hypertension in rats but was ineffective in developed DOCA-saline hypertension. Treatment with intraventricular 6-OH-DA caused a deficit of saline intake. The preventive effect of intraventricular 6-OH-DA on rise in blood pressure was not secondary to a reduction in salt intake since vehicle-treated rats given a similar reduced salt intake became fully hypertensive. The development of DOCA-saline hypertension was unaffected by pretreatment with intraspinal administration of 6-OH-DA, which produced a virtually complete loss of noradrenaline [norepinephrine] only in the spinal cord. Apparently brain adrenergic neurons may participate in the production of DOCA-saline hypertension but the noradrenergic projections in the spinal cords are not essential for this process.