title: The influence of enteral obestatin administration to suckling rats on intestinal contractility.
abstract: This study investigated the effect of enteral administration of obestatin on the contractility of whole-thickness preparations of duodenum and middle jejunum, as well as on the morphology of the enteric nervous system (ENS). Suckling rats were assigned to 3 groups (n=12) treated with: C-saline solution; LO-obestatin (125nmol/kgb.wt); HO-obestatin (250nmol/kgb.wt). Saline solution or obestatin were administered twice daily, from the 14th to the 21st day of life. Sections were studied in an organ bath, for isometric recording in the presence of acetylocholine (ACh), atropine (ATR) and tetradotoxin (TTX). Thickness of intestinal muscularis layer, the number of interstitial cells of Cajal (ICC) were measured in the paraffin sections. The immunodetection of Muscarinic Acetylocholine Receptor 2 (M2 receptor) was performed in the intestinal segments. In both intestinal segments HO treatment decreased the amplitude of spontaneous contraction compared to that observed in the C group. In the middle jejunum, the LO treatment also decreased the amplitude. TTX and ATR had no effect on amplitude of spontaneous contraction in the jejunum of LO and HO-treated animals. Compared to the C group, duodenal sections from HO animals and middle jejunum sections from LO and HO groups displayed a lower amplitude in response to ACh and EFS evoked contraction. An increase in the thickness of the muscularis layer was observed in the duodenum of LO and HO groups whereas the number ICC did not change significantly after treatment with obestatin. Moreover, the enteral administration of obestatin did not effect significantly on the cytoplasmic expression of M2 receptor in the jejunum. Our study demonstrated that enteral administration of obestatin to suckling rats influences small intestine contractility in the segment specific manner.
authors.affiliation: Department of Animal Physiology, The Kielanowski Institute of Animal Physiology and Nutrition, Polish Academy of Sciences, Jabłonna, Poland. Electronic address: m.slupecka@ifzz.pl.
authors.forename: M
authors.initials: M
authors.lastname: Słupecka
authors.affiliation: Department of Animal Physiology, The Kielanowski Institute of Animal Physiology and Nutrition, Polish Academy of Sciences, Jabłonna, Poland.
authors.forename: P
authors.initials: P
authors.lastname: Grzesiak
authors.affiliation: Department of Animal Physiology, The Kielanowski Institute of Animal Physiology and Nutrition, Polish Academy of Sciences, Jabłonna, Poland.
authors.forename: J
authors.initials: J
authors.lastname: Kwiatkowski
authors.affiliation: Department of Physiological Sciences, Faculty of Veterinary Medicine, Warsaw University of Life Sciences, Warsaw, Poland.
authors.forename: M
authors.initials: M
authors.lastname: Gajewska
authors.affiliation: Laboratory of Physiology, Institute for Environmental Sciences and Graduate School of Nutritional and Enviromental Science, University of Shizuoka, Japan.
authors.forename: A
authors.initials: A
authors.lastname: Kuwahara
authors.affiliation: Department of Medical Biochemistry, Kobe Pharmaceutical University, Japan.
authors.forename: I
authors.initials: I
authors.lastname: Kato
authors.affiliation: Department of Animal Physiology, The Kielanowski Institute of Animal Physiology and Nutrition, Polish Academy of Sciences, Jabłonna, Poland.
authors.forename: J
authors.initials: J
authors.lastname: Woliński
mesh_terms: D000109:Acetylcholine / Q000494:pharmacology; D000818:Animals; D002452:Cell Count; D004558:Electric Stimulation; D004750:Enteral Nutrition; D005260:Female; D005769:Gastrointestinal Motility / Q000187:drug effects / Q000502:physiology*; D054439:Ghrelin / Q000008:administration & dosage* / Q000494:pharmacology*; D056885:Interstitial Cells of Cajal / Q000166:cytology / Q000187:drug effects; D007422:Intestines / Q000187:drug effects / Q000502:physiology*; D008297:Male; D009119:Muscle Contraction / Q000187:drug effects*; D019009:Proto-Oncogene Proteins c-kit / Q000378:metabolism; D051381:Rats; D043585:Receptor, Muscarinic M2; D013779:Tetrodotoxin / Q000494:pharmacology
chemical_list: D054439:Ghrelin; D043585:Receptor, Muscarinic M2; D013779:Tetrodotoxin; D019009:Proto-Oncogene Proteins c-kit; D000109:Acetylcholine
keywords: Contractility; Intestine; Obestatin; Rat