Sun M K, Spyer K M
Department of Physiology, Royal Free Hospital School of Medicine, London, U.K.
J Auton Nerv Syst. 1991 Apr;33(1):79-84. doi: 10.1016/0165-1838(91)90020-4.
The activity of spinal projecting 'vasomotor' neurones of the rostroventrolateral medulla (RVL) has been recorded in anaesthetised and paralysed rats. They responded to carotid body chemoreceptor stimulation (0.208 M NaH2PO4) with an increase in discharge that preceded an evoked increase in arterial blood pressure. This initial excitatory response was followed by a fall in discharge correlated to the rise in blood pressure. RVL neurones, which had equivalent sensitivity to baroreceptor inputs but no spinal projecting axons, failed to exhibit the initial excitatory response on chemoreceptor stimulation. These observations suggest that the pressor response to chemoreceptor stimulation is mediated, at least partially, by excitation of RVL-spinal 'vasomotor' neurones.
