CENTRAL NEURONS AND NEUROTRANSMITTERS IN THE CONTROL OF BLOOD-PRESSURE

1. In this paper we review recent work from our laboratory on two majo r pathways important in the central control of blood pressure. 2. We r eport experiments on the sympatho-excitatory bulbospinal pathway from the rostral ventral medulla. Here we focus particularly on the role of excitatory amino acids. 3. We review studies on the short inhibitory or depressor pathway ascending from the caudal to the rostral ventral medulla, which is thought to use gamma-aminobutyric acid (GABA) as its neurotransmitter. We report on experiments with the immediate early g ene, c-fos, demonstrating that its expression in the bulbospinal press er neurons is increased by stimuli that activate these nerves, and tha t this expression can be blocked in vivo by treatment with an antisens e oligonucleotide. We also show that basal and stimulated expression o f the c-fos gene is important in the central control of blood pressure .