Summary
Behavioral and physiological studies have revealed increasing evidence in thirst, hunger, energy and water metabolism for the importance of visceral input to the brain as well as central modulation of visceral events. Recent work in our laboratory has now revealed some new information about the central course of these afferent and efferent systems. From our work and others there is now good evidence that the bed of the hepatic-portal system contains sodium and osmoreceptors. Our electrophysiological and histochemical studies show that one branch overlaps the gustatory pathway. That is, involves the vagus nerve, nucleus tractus solitarius, parabrachial nucleus and ventro-basal thalamus (VBC). Another branch goes not to VBC but to the supra-optic nucleus. At the one level so far investigated clear evidence was obtained for convergence on single cells of visceral and gustatory inputs. It may well occur at other levels. A parallel and perhaps interacting efferent system more related to energy regulation has also been explored. The major parasympathetic output to the viscera are the axons of the brain stem dorsal-motor nucleus (DMV) forming the vagus nerves. We have shown that the paraventricular nucleus, which was known to project to DMV, is the only structure above the brain stem that has a direct input to DMV. However, since the nucleus of the solitary tract and reticular formation send fibers to the DMV the neural substrate exists for considerable indirect input. The significance of these results is that it provides a central neural substrate of the 2-way pathways linking brain and viscera. Thus, we now know more about neural control mechanisms involved in several motivational and metabolic systems. The close contiguity and even convergence of gustatory and visceral afferents may help to explain taste-aversion learning and alterations in the hedonics of taste under different nutritional states. The unique place of the paraventricular nucleus in relation to parasympathetic efferents will doubtless lead to new knowledge of the role of the brain in control of energy metabolism.
Article PDF
Similar content being viewed by others
References
Adachi A, Niijima A, Jacobs HL (1976) An hepatic osmoreceptor mechanism in the rat: electrophysiological and behavioral studies. Am J Physiol 213: 1043–1049
Cabanac M, Minaire Y, Adair E (1968) Influence of internal factors on the pleasantness of a gustative sweet sensation. Comm Behav Biol Pt A1: 77–82
de Olmos JS (1978) An improved HRP method for the study of central nervous connections. Exp Brain Res 29: 541–551
Frenk H, Rogers GH (1979) The suppressant effect of naloxone on food and water intake in the rat. Behav Neural Biol 26: 23–40
Grijalva C, Novin D, Cooper P (in press) Facilitation of recovery by propanthaline bromide after lateral hypothalamic area damage. Brain Res Bull
Grill HJ, Norgren R (1978) Chronic decrebrate rats demonstrate satiation but not bait shyness. Science 201: 267–269
Haberich FJ (1968) Osmoreception in the portal circulation. Fed Proc 27: 1137–1141
Hardcastle J, Hardcastle PT, Sanford PA (1978) Effect of actively transported hexoses on afferent nerve discharge from rat small intestine. J Physiol (Lond) 285: 71–84
Hermann G, Novin D (in press) Morphine inhibition of parabrachial taste units reversed by naloxone. Brain Res Bull
Johansson O, Hokfelt RP, Elde M, Schultzberg M, Terenius L (1978) Immunohistochemical distribution of enkephalin neurons. In: Costa E, Trabucchi M (eds) Advances in biochemical pharmacology, vol 18. Raven Press, New York, p 51–70
Liebowitz SF (1978) Paraventricular nucleus: a primary site mediating adrenergic stimulation of feeding and drinking. Pharmacol Biochem Behav 8: 163–175
Matsuo Y, Seki A (1978) The coordination of gastrointestinal hormones and the autonomic nerves. Am J Gastroenterol 69: 21–50
Mesulam MM (1978) Tertramethylbenzidine for horseradish peroxidase: a noncarcinogenic blue reaction product with superior sensitivity for visualizing neural afferents and efferents. J Histochem Cytochem 26: 106–117
Niijima A (1979) Control of liver function and neuroendocrine regulation of blood glucose. In: Brooks CM, Koizumi K, Sato A (eds) Integrative functions of the autonomic nervous system. University of Tokyo Press, Tokyo, p 68–83
Norgren R, Leonard CM (1975) Ascending central gustatory pathways. J Comp Neurol 150: 217–238
Novin D, Gonzalez MF, Sanderson JD (1976) Paradoxical increased feeding following glucose infusions in recovered lateral rats. Am J Physiol 230: 1084–1089
Novin D, VanderWeele DA (1977) Visceral involvement in feeding: There is more to regulation than the hypothalamus. In: Sprague J, Epstein AN (eds) Progress in psychobiology and physiological psychology, vol 7. Academic Press, New York, p 194–241
Paintal AS (1973) Vagal sensory receptors and their reflex effects. Physiol Rev 53: 159–227
Panksepp J (1974) Hypothalamic regulation of energy balance and feeding behavior. Fed Proc 33: 1150–1165
Rogers RC, Kita H, Butcher LL, Novin D (in press) Afferent projections to the dorsal motor nucleus of the vagus. Brain Res Bull
Rogers RC, Novin D, Butcher LL (1979) Electrophysiological and neuroanatomical studies of hepatic portal osmo- and sodium-receptive afferent projections within the brain. J Autonom Nerv Syst 1: 183–202
Saper CB, Loewy AD, Swanson LW, Cowan WM (1976) Direct hypothalamic-autonomic connections. Brain Res 117: 305–312
Schmitt M (1973) Influence of hepatic portal receptors on hypothalamic feeding and satiety centers. Am J Physiol 225: 1089–1095
Sharma KN (1967) Receptor mechanisms in the alimentary tract: their excitation and functions. In: Code C (ed) Handbook of physiology, vol I. American Physiological Society, Washington DC, p 225–237
York DA, Bray GA (1972) Dependence of hypothalamic obesity on insulin, the pituitary and the adrenal gland. Endocrinology 90: 885–894
Author information
Authors and Affiliations
Rights and permissions
About this article
Cite this article
Novin, D., Rogers, R.C. & Hermann, G. Visceral afferent and efferent connections in the brain. Diabetologia 20 (Suppl 1), 331–336 (1981). https://doi.org/10.1007/BF00254500
Published:
Issue Date:
DOI: https://doi.org/10.1007/BF00254500