Effect of ghrelin administration on phagocytic activity in acute cold-restraint stress exposed rats

• Published in: Regulatory peptides 2007-02, Vol.138 (2), p.113-117
• Main Authors: Tümer, Cemil, Bilgin, Hakkı Murat, Obay, Basra Deniz, Diken, Hüda, Taşdemir, Ezel, Şermet, Abdurrahman
• Format: Article
• Language: English
• Subjects: Acute cold-restraint stress; Animals; Biological and medical sciences; Cold Temperature; Fundamental and applied biological sciences. Psychology; Ghrelin; Inducible nitric oxide synthase; Injections, Intraperitoneal; Macrophages, Peritoneal - drug effects; Macrophages, Peritoneal - physiology; Male; Nitrites - blood; Peptide Hormones - administration & dosage; Peptide Hormones - blood; Peptide Hormones - pharmacology; Phagocytic activity; Phagocytosis - drug effects; Rats; Rats, Wistar; Restraint, Physical; Vertebrates: endocrinology
• ISSN: 0167-0115; 1873-1686
• DOI: 10.1016/j.regpep.2006.08.010

Ghrelin, an endogenous ligand for growth hormone secretagogue receptor, was identified in the rat stomach. This peptide acts through nitric oxide (NO) by expressing endothelial nitric oxide synthase (eNOS) and down regulating inducible nitric oxide synthase (iNOS) at its gastroproprotective effect against restraint stress induced damage. Recently the ghrelin receptor has also been detected in peripheral systems including immune tissue. We have investigated the possible effect of ghrelin on phagocytic activity of peritoneal macrophages in acute cold-restraint stress (ACRS) exposed rats. The rats were divided into control, stress and ghrelin groups. In ghrelin groups, single dose and three days consecutive dose of ghrelin (20 μg/kg. i.p.) were applied to rats that were exposed to ACRS for 4 h. 1 ml of saline was injected i.p. after ACRS for 3 consecutive days to the rats of the stress groups. Ghrelin administration reduced the increased phagocytic activity induced by ACRS. We conclude that ghrelin exerts an important role at macrophage phagocytic activity in ACRS exposed rats.