EFFECT OF CHRONIC HYPOTHALAMIC STIMULATION UPON CHOLESTEROL-INDUCED ATHEROSCLEROSIS IN THE RABBIT*

Abstract

Electrodes were permanently inserted as close as possible to the ventral medial nucleus of the hypothalamus of 19 male rabbits. After healing, biphasic, 60 cycles, monitored-currents of 0.2 to 0.8 ma were administered at a strength of 1 to 6 volts in pulses of 0.2 msec duration. This stimulation was done 4 times daily, 6 days a week for 3 months. Each period of stimulation consisted of ten 30-second episodes of current application interspersed with ten 30-second intervals of pause. Fourteen of the stimulated rabbits ate a diet enriched with 1% cottonseed oil and 1% cholesterol (Series A). Series B consisted of the remaining 5 stimulated rabbits who were placed on a normal diet. Series C consisted of 16 normal rabbits who ate the oil and cholesterol enriched diet. Average serum values (in mg%) obtained after 3 months for cholesterol, phospholipid, and total lipids were 1587, 609, and 2785, respectively, for Series A; and for Series C they were 1215, 435, and 2117, respectively. Series B did not show blood lipid rises or atherosclerosis. Series A showed much greater atherosclerotic involvement of aortic and coronary vasculature than did Series C. It is concluded that central nervous system mechanisms exist which are capable of significantly influencing arterial atherogenesis.