The neuronal reactions of the perinuclear zone of the hypothalamic supraoptic nucleus in rats to stimulation of the hypophyseal stalk and the hippocampus

: The orthodromically activated neurons (OAN) were recorded in the hypothalamic supraoptic area under the hypophysial stalk stimulation. They were distinguished by the pattern of the orthodromic activation and the recording sites. More than a half of OAN responded to the stimulation of ventral hippocampus and the responses were primary excitatory in all cases. The similarity in most OAN responses to the hippocampal and the hypophysial stalk stimulation was found. The peculiar influence of the hippocampus on OAN was analyzed, their location in the supraoptic nucleus or perinuclear zone and the supposed morphofunctional connections with the antidromically identified neurosecretory cells being taken into account.