Published online before print March 1, 2004, doi: 10.1161/01.HYP.0000122803.91559.55
| ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
(Hypertension. 2004;43:977.)
© 2004 American Heart Association, Inc.
Scientific Contributions |
Ghrelin Acts at the Nucleus of the Solitary Tract to Decrease Arterial Pressure in Rats
From the Department of Medicine and Clinical Science, Graduate School of Medical Sciences, Kyushu University, Maidashi 3-1-1, Higashi-ku, Fukuoka 812-8582, Japan.
Correspondence to Kiyoshi Matsumura, MD, Department of Medicine and Clinical Science, Graduate School of Medical Sciences, Kyushu University, Maidashi 3-1-1, Higashi-ku, Fukuoka 812-8582, Japan. E-mail matsumk{at}intmed2.med.kyushu-u.ac.jp
Ghrelin is an orexigenic peptide originally isolated from the stomach. Intracerebroventricular administration of ghrelin has been shown to elicit decreases in arterial pressure and renal sympathetic nerve activity in conscious rabbits. The aim of the present study was to determine the role of ghrelin in the brain stem in cardiovascular responses in rats. Unilateral microinjection of ghrelin into the nucleus of the solitary tract significantly decreased the mean arterial pressure and heart rate (–17.3±0.8 mm Hg and –13.6±3.5 bpm by 20 pmol). The microinjection of ghrelin into the nucleus of the solitary tract also suppressed the renal sympathetic nerve activity (–29.5±3.4%; P<0.0001). Pretreatment with intravenous injection of pentolinium (5 mg/kg), a ganglion-blocking agent, eliminated these cardiovascular responses induced by the microinjection of ghrelin (20 pmol) into the nucleus of the solitary tract; however, pretreatment with intravenous injection of atropine sulfate (0.1 mg/kg), an antagonist of muscarinic acetylcholine receptors, failed to prevent them. In contrast, unilateral microinjection of ghrelin into the area postrema, rostral, and caudal ventrolateral medulla caused no significant changes in the mean arterial pressure and heart rate. On the other hand, immunohistochemical study revealed that the receptor for ghrelin, the growth hormone secretagogue receptor, was expressed in the neuronal cells of the nucleus of the solitary tract and the dorsal motor nucleus of the vagus, but not in the cells of the area postrema. These results suggest that ghrelin acts at the nucleus of the solitary tract to suppress sympathetic activity and to decrease arterial pressure in rats.
Key Words: blood pressure • immunohistochemistry • rats
This article has been cited by other articles:
 |
|
 |
|
  M. Kobashi, M. Yanagihara, M. Fujita, Y. Mitoh, and R. Matsuo Fourth ventricular administration of ghrelin induces relaxation of the proximal stomach in the rat Am J Physiol Regulatory Integrative Comp Physiol, February 1, 2009; 296(2): R217 - R223. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 H. Ashrafian, C. W. le Roux, A. Darzi, and T. Athanasiou Effects of Bariatric Surgery on Cardiovascular Function Circulation, November 11, 2008; 118(20): 2091 - 2102. [Full Text] [PDF]
|
|
|
|
 |
|
 D. O. Schwenke, T. Tokudome, I. Kishimoto, T. Horio, M. Shirai, P. A. Cragg, and K. Kangawa Early Ghrelin Treatment after Myocardial Infarction Prevents an Increase in Cardiac Sympathetic Tone and Reduces Mortality Endocrinology, October 1, 2008; 149(10): 5172 - 5176. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
M. Yukawa, D. S. Weigle, C. D. Davis, B. T. Marck, and T. Wolden-Hanson Peripheral ghrelin treatment stabilizes body weights of senescent male Brown Norway rats at baseline and after surgery Am J Physiol Regulatory Integrative Comp Physiol, May 1, 2008; 294(5): R1453 - R1460. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 T. Soeki, I. Kishimoto, D. O. Schwenke, T. Tokudome, T. Horio, M. Yoshida, H. Hosoda, and K. Kangawa Ghrelin suppresses cardiac sympathetic activity and prevents early left ventricular remodeling in rats with myocardial infarction Am J Physiol Heart Circ Physiol, January 1, 2008; 294(1): H426 - H432. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 R. Wu, W. Dong, M. Zhou, F. Zhang, C. P. Marini, T. S. Ravikumar, and P. Wang Ghrelin Attenuates Sepsis-induced Acute Lung Injury and Mortality in Rats Am. J. Respir. Crit. Care Med., October 15, 2007; 176(8): 805 - 813. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 A. Baessler, M. Fischer, B. Mayer, M. Koehler, S. Wiedmann, K. Stark, A. Doering, J. Erdmann, G. Riegger, H. Schunkert, et al. Epistatic interaction between haplotypes of the ghrelin ligand and receptor genes influence susceptibility to myocardial infarction and coronary artery disease Hum. Mol. Genet., April 15, 2007; 16(8): 887 - 899. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
E. Grossini, C. Molinari, D. A. S. G. Mary, E. Ghigo, G. Bona, and G. Vacca Intracoronary Ghrelin Infusion Decreases Coronary Blood Flow in Anesthetized Pigs Endocrinology, February 1, 2007; 148(2): 806 - 812. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
R. Nogueiras, P. Pfluger, S. Tovar, M. Arnold, S. Mitchell, A. Morris, D. Perez-Tilve, M. J. Vazquez, P. Wiedmer, T. R. Castaneda, et al. Effects of Obestatin on Energy Balance and Growth Hormone Secretion in Rodents Endocrinology, January 1, 2007; 148(1): 21 - 26. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 L. F. Faulconbridge, H. J. Grill, and J. M. Kaplan Distinct Forebrain and Caudal Brainstem Contributions to the Neuropeptide Y Mediation of Ghrelin Hyperphagia Diabetes, July 1, 2005; 54(7): 1985 - 1993. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 K. Rahmouni, M. L.G. Correia, W. G. Haynes, and A. L. Mark Obesity-Associated Hypertension: New Insights Into Mechanisms Hypertension, January 1, 2005; 45(1): 9 - 14. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
P. M. Pilowsky Neurotransmission in Central Cardiovascular Control: 10 Suggestions for Microinjections Hypertension, May 1, 2004; 43(5): 945 - 946. [Full Text] [PDF]
|
|