Am J Physiol Gastrointest Liver Physiol 287: G612-G619, 2004.
First published April 23, 2004; doi:10.1152/ajpgi.00431.2003
0193-1857/04 $5.00
NEUROREGULATION AND MOTILITY
Regional gastric contractility alterations in a diabetic gastroparesis mouse model: effects of cholinergic and serotoninergic stimulation
Arlene N. James,1
James P. Ryan,2
Michael D. Crowell,3 and
Henry P. Parkman1,2
Departments of 1Medicine and 2Physiology, Temple University School of Medicine, Philadelphia, Pennsylvania 19140; and 3Department of Medicine, Mayo Clinic Scottsdale, Scottsdale, Arizona 85259
Submitted 2 October 2003
; accepted in final form 12 April 2004
The C57BLKS/J db/db mouse develops hyperglycemia and has delayed gastric emptying that is improved with tegaserod, a partial 5-HT4 agonist. Our aims here were to determine regional gastric contractility alterations in C57BLKS/J db/db mice and to determine the effects of serotonin and tegaserod. The contractile effects of bethanechol, serotonin, and tegaserod in fundic, antral, and pyloric circular muscle were compared in C57BLKS/J db/db mice and normal littermates. The effects of tetrodotoxin, atropine, and 5-HT receptor antagonists were studied. Contractions in response to bethanechol were decreased in the fundus, similar in the antrum, but increased in the pylorus in diabetic mice compared with controls. Serotonin and, to a lesser extent, tegaserod caused contractions that were more pronounced in the fundus than in the antrum and pylorus in both diabetic and normal mice. Serotonin-induced contractions were partially inhibited by atropine, the 5-HT4 antagonist GR113808, and the 5-HT2 antagonist cinanseron but not tetrodotoxin. Regional gastric contractility alterations are present in this diabetic gastroparesis mouse model. Fundic contractility was decreased, but pyloric contractility was increased in the pylorus to cholinergic stimulation in diabetic mice. Serotonin's contractile effect is mediated, in part, through muscarinic, 5-HT2, and 5-HT4 receptors. This study suggests that fundic hypomotility and pyloric hypercontractility, rather than antral hypomotility, play important roles for the gastric dysmotility that occurs in diabetes.
serotonin; tegaserod
Address for reprint requests and other correspondence: H. P. Parkman, Gastroenterology Section, Dept. of Internal Medicine, Temple Univ. School of Medicine, 3401 N. Broad St., Philadelphia, PA 19140 (E-mail: henry.parkman{at}temple.edu)
This article has been cited by other articles:

|
 |

|
 |
 
L. B Lemke, A. B Rogers, P. R Nambiar, and J. G Fox
Obesity and non-insulin-dependent diabetes mellitus in Swiss-Webster mice associated with late-onset hepatocellular carcinoma
J. Endocrinol.,
October 1, 2008;
199(1):
21 - 32.
[Abstract]
[Full Text]
[PDF]
|
 |
|

|
 |

|
 |
 
P. R. R. Gangula, W. L. Maner, M.-A. Micci, R. E. Garfield, and P. J. Pasricha
Diabetes induces sex-dependent changes in neuronal nitric oxide synthase dimerization and function in the rat gastric antrum
Am J Physiol Gastrointest Liver Physiol,
March 1, 2007;
292(3):
G725 - G733.
[Abstract]
[Full Text]
[PDF]
|
 |
|

|
 |

|
 |
 
Z. S. Li, C. Schmauss, A. Cuenca, E. Ratcliffe, and M. D. Gershon
Physiological modulation of intestinal motility by enteric dopaminergic neurons and the D2 receptor: analysis of dopamine receptor expression, location, development, and function in wild-type and knock-out mice.
J. Neurosci.,
March 8, 2006;
26(10):
2798 - 2807.
[Abstract]
[Full Text]
[PDF]
|
 |
|
Copyright © 2004 by the American Physiological Society.