Presence of glutamate receptor subtypes on barosensitive neurons in the nucleus tractus solitarius of the dog

Afferent baroreceptor information is transmitted to the nucleus tractus sol itarius (NTS) in the dorsal medulla where glutamate is thought to be the pr imary neurotransmitter. However, the subtypes of glutamate receptors involv ed in the baroreflex remain to be established, The present study compared t he distribution of immunohistochemically labeled ionotropic receptor subtyp es to the distribution of physiologically stimulated barosensitive neurons in the NTS of the dog and also identified ionotropic receptor subtypes loca ted on barosensitive neurons. Both NMDA and non-NMDA receptors were located in barosensitive areas and on barosensitive neurons, suggesting that both may be involved in the baroreflex. (C) 1999 Elsevier Science Ireland Ltd. A ll rights reserved.