Influence of the corpus striatum upon electrical potentials of the liver

Abstract

The effect of stimulation of the caudate nucleus, hypothalamus, midbrain tegmentum, splanchnic nerve, or vagus nerve upon the liver was studied in cats using d-c potentials of the liver surface (LP) as an indicator. Stimulation of these areas or of the splanchnic nerve induced a gradual increase of the positive LP. The maximum (1–2 mv) was reached about 30 sec after the beginning of the reaction. The gradually declining curve returned to or close to the resting value about 30 to 60 sec later. Vagal stimulation usually produced a fluctuation of LP to the negative side. In control experiments, stimulation of the pole and basal parts of the frontal lobe, of the sigmoid gyri and of the dura did not significantly change LP. The effect of caudate stimulation upon the liver did not depend on the corticofugal fibers originating in the sigmoid gyri and frontal lobe, in contrast to the effect upon smooth muscles. The effect of stimulation of the caudate nucleus persisted after extensive homolateral lesions of the pallidum or of the amygdala, but it was no longer demonstrable after extensive combined lesions of these ganglia. It was distinctly decreased by large hypothalamic lesions on the side of the caudate stimulation and practically abolished by extensive bilateral lesions in the caudal hypothalamus. Transection of the spinal cord above the origin of the splanchnic nerves prevented or abolished the effect of stimulation of the caudate nucleus or the hypothalamus upon LP, whereas this reaction persisted after bilateral vagotomy. In aggreement with the assumption that the influence of the caudate nucleus and of the hypothalamus upon the liver is part of the central temperature regulation, it was found that the rise in LP was accompanied by an elevation of the liver temperature.