Distribution of glutamate- and GABA-immunoreactive neurons projecting to the vasomotor center of the intermediolateral nucleus of the lower thoracic cord of Wistar rats: a double-labeling study.

The purpose of this study was to survey distribution of glutamatergic and GABAergic neurons in the brainstem with projections to the vasomotor center in the intermediolateral nucleus of the T11 segment of Wistar rats. This was done with retrograde transport of WGA-HRP and immunoreaction to glutamate and GABA. HRP/glutamate-labeled neurons were distributed in the rostral ventrolateral medulla (RVLM, 29%), A5 noradrenaline cell area (16%), paraventricular nucleus of the hypothalamus (14%) and caudal ventrolateral medulla (CVLM, 11%), while HRP/GABA-labeled neurons in the RVLM (65%) and CVLM (24%). This indicates that the glutamatergic and GABAergic neurons projecting to the spinal vasomotor center originate mainly from the RVLM and CVLM.