Interleukin 2 modifies the bioelectric activity of some neurosecretory nuclei in the rat hypothalamus

Introduction of 15-30 U of interleukin-2 (IL-2) into the 3rd ventricle of Wistar rats was followed by a marked and significant decrease in neuron discharge frequency in the ventromedial nucleus of hypothalamus and a marked increase in the supraoptic and paraventricular nuclei. The monoclonal antibody ART62 partly blocked these effects. The conventional anti-IL-2 receptor monoclonal antibody ART18 had only a non-significant influence on the effects of IL-2. Since the supraoptic and paraventricular nuclei secrete the antidiuretic hormone, their excitation may offer a partial explanation of the considerable water retention observed during IL-2 therapy against neoplasia.