The role of the septal nuclei in controlling the activity of vagosensitive neurons in the solitary tract nucleus in cats.

Studies on cats anesthetized with a mixture of Nembutal and chloralose were performed to study the descending influences of single, paired, and frequent stimulation of the lateral septal nucleus (LSN) and bed nucleus of the stria terminalis (BNST) on the activity of viscerosensory neurons in the solitary tract nucleus, identified by stimulation of the cervical part of the vagus nerve. Of 70 units recorded in the solitary tract nucleus, 50 were identified as primary and secondary input vagus neurons. Single stimuli applied to the septal nuclei induced initial excitation in 30% (15 units) of vagus neurons.

Spontaneous and evoked hypothalamic unit activity in kittens during development.

Spontaneous and evoked hypothalamic unit activity in response to sensory stimuli was studied in acute experiments on anesthetized kittens. After the second day of postnatal development, spontaneous unit activity can be recorded in the posterior hypothalamus. Evoked responses to sciatic nerve stimulation were recorded on the fourth to fifth day after birth.