BIOLOGICAL FEATURES OF DORSAL VAGAL NUCLE US

Stereological, histochemical, and electron microscopic approaches were applied to study the cellular and synaptic structure of the rat dorsa l vagal nucleus (DVN). The cellular organization of the DNV does not a llow one to distinguish any subnuclei, but the conspicious population of mostly small neurons in the lateral nucleus' rostral stretch lackin g AChE activity. DVN neurons with high and moderate AChE activities we re evident on the 5th postnatal day. Their number increased on day 7. In this critical period of brain sex differentiation, sex dimorphism w as observed in the activity of DVN cholinergic neurons. Electron micro scopic studies showed a great variety of DVN patterns. The fact that i n the rat DVN there are complicated synaptic structures resembling glo merules is described in the paper. Two types of synaptic glomerules we re identified. The results suggest that DVN can be seen as a sex-depen dent brain region involved in sufficiently high information processing .