|
|
||||||||
APPETITE, OBESITY AND METABOLISM
Institute of Veterinary Physiology, University of Zurich, 8057 Zurich, Switzerland
Submitted 17 June 2003 ; accepted in final form 27 August 2003
Amylin is a peptide hormone that is cosecreted with insulin from the pancreas during and after food intake. Peripherally injected amylin potently inhibits feeding by acting on the area postrema (AP), a circumventricular organ lacking a functional blood-brain barrier. We recently demonstrated that AP neurons are excited by a near physiological concentration of amylin. However, the subsequent neuronal mechanisms and the relevance of endogenously released amylin for the regulation of food intake are poorly understood. Therefore, we investigated 1) amylin's contribution to feeding-induced c-Fos expression in the rat AP and its ascending projection sites, and 2) amylin's ability to reverse fasting-induced c-Fos expression in the lateral hypothalamic area (LHA). Similar to amylin (20 µg/kg sc), refeeding of 24-h food-deprived rats induced c-Fos expression in the AP, the nucleus of the solitary tract, the lateral parabrachial nucleus, and the central nucleus of the amygdala. In AP-lesioned rats, the amylin-induced c-Fos expression in each of these sites was blunted, indicating an AP-mediated activation of these structures. Pretreatment with the amylin antagonist AC-187 (1 mg/kg sc) inhibited feeding-induced c-Fos expression in the AP. Food deprivation activated LHA neurons, a response known to be associated with hunger. This effect was reversed within 2 h after refeeding and also in nonrefed animals that received amylin. In summary, our data provide the first evidence that feeding-induced amylin release activates AP neurons projecting to subsequent relay stations known to transmit meal-related signals to the forebrain. Activation of this pathway seems to coincide with an inhibition of LHA neurons.
food intake; immunohistochemistry; brain stem; lateral hypothalamic area
This article has been cited by other articles:
![]() |
C. Becskei, T. A. Lutz, and T. Riediger Diet-derived nutrients mediate the inhibition of hypothalamic NPY neurons in the arcuate nucleus of mice during refeeding Am J Physiol Regulatory Integrative Comp Physiol, July 1, 2009; 297(1): R100 - R110. [Abstract] [Full Text] [PDF] |
||||
![]() |
J. D. Roth, H. Maier, S. Chen, and B. L. Roland Implications of Amylin Receptor Agonism: Integrated Neurohormonal Mechanisms and Therapeutic Applications Arch Neurol, March 1, 2009; 66(3): 306 - 310. [Full Text] [PDF] |
||||
![]() |
M. Fry and A. V. Ferguson Ghrelin modulates electrical activity of area postrema neurons Am J Physiol Regulatory Integrative Comp Physiol, March 1, 2009; 296(3): R485 - R492. [Abstract] [Full Text] [PDF] |
||||
![]() |
C. J. Price, T. D. Hoyda, and A. V. Ferguson The Area Postrema: A Brain Monitor and Integrator of Systemic Autonomic State Neuroscientist, April 1, 2008; 14(2): 182 - 194. [Abstract] [PDF] |
||||
![]() |
C. Mack, J. Wilson, J. Athanacio, J. Reynolds, K. Laugero, S. Guss, C. Vu, J. Roth, and D. Parkes Pharmacological actions of the peptide hormone amylin in the long-term regulation of food intake, food preference, and body weight Am J Physiol Regulatory Integrative Comp Physiol, November 1, 2007; 293(5): R1855 - R1863. [Abstract] [Full Text] [PDF] |
||||
![]() |
S. R. Smith, J. E. Blundell, C. Burns, C. Ellero, B. E. Schroeder, N. C. Kesty, K. S. Chen, A. E. Halseth, C. W. Lush, and C. Weyer Pramlintide treatment reduces 24-h caloric intake and meal sizes and improves control of eating in obese subjects: a 6-wk translational research study Am J Physiol Endocrinol Metab, August 1, 2007; 293(2): E620 - E627. [Abstract] [Full Text] [PDF] |
||||
![]() |
P. Kobelt, M. Goebel, A. Stengel, M. Schmidtmann, I. R. van der Voort, J. J. Tebbe, R. W. Veh, B. F. Klapp, B. Wiedenmann, L. Wang, et al. Bombesin, but not amylin, blocks the orexigenic effect of peripheral ghrelin Am J Physiol Regulatory Integrative Comp Physiol, October 1, 2006; 291(4): R903 - R913. [Abstract] [Full Text] [PDF] |
||||
![]() |
T. A. Lutz Hunger and satiety: one brain for two? Am J Physiol Regulatory Integrative Comp Physiol, October 1, 2006; 291(4): R900 - R902. [Full Text] [PDF] |
||||
![]() |
W. A. Cupples Physiological regulation of food intake Am J Physiol Regulatory Integrative Comp Physiol, June 1, 2005; 288(6): R1438 - R1443. [Full Text] [PDF] |
||||
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
| Visit Other APS Journals Online |