Experimental evidence for hypothalamic paraventricular nucleus involvement in the regulation of carbohydrate homeostasis.

An attempt was made to elucidate whether the hypothalamic paraventricular nucleus (PVN) is involved in carbohydrate homeostasis regulation in rats. The cellular responses to various disturbances of homeostasis were studied in the neuronal subdivisions (subnuclei) of the PVN. The responses were assessed in terms of changes in the sizes of the cell nuclei, nucleoli, and cytoplasm, and by the ultrastructural changes evident in cellular organelles. Significant cellular responses were observed in several subnuclei, with the nature of the responses being determined by the type of homeostatic alteration. The results indicate the possible involvement of the PVN subnuclei in the regulation of carbohydrate homeostasis.