title: Maturation of central autonomic control of the circulation.
abstract: Postnatal maturation of central neural regulation of cardiovascular function is being examined in developing swine. Three major types of investigations have been undertaken: 1) alterations of inputs from visceral and somatic afferents, e.g., baroreceptor manipulation, stimulation of sciatic nerves; 2) stimulation of central vasoactive sites; 3) subjecting the animals to the stresses of hemorrhage, hypoxia, or hypercapnia. Our findings indicate that cardiovascular reflexes mature at different postnatal ages. For example, the J-receptor reflex had almost the adult pattern of response at birth, whereas the Bezold-Jarisch reflex had a markedly delayed postnatal maturation. Recordings of spontaneous discharge in a major efferent sympathetic supply, i.e., the greater splanchnic nerve, have indicated that neural innervation to the adrenal medulla and splanchnic vasculature is present at birth in piglets.
mesh_terms: D000818:Animals; D000831:Animals, Newborn; D001783:Blood Flow Velocity; D002196:Capillaries / Q000294:innervation; D006321:Heart / Q000294:innervation; D006439:Hemodynamics; D006470:Hemorrhage / Q000503:physiopathology; D011311:Pressoreceptors / Q000502:physiology; D012018:Reflex / Q000502:physiology; D012212:Rheology; D013552:Swine; D013564:Sympathetic Nervous System / Q000502:physiology*; D014666:Vasomotor System / Q000502:physiology*