Expression and motor effects of secretin in small and large intestine of the rat

• Immunocytochemistry and in situ hybridization revealed abundant secretin expressing cells on duodenal villi with a gradual decrease throughout the small intestines of the rat. They were absent in pancreas, stomach and colon. Secretin caused relaxation of rat intestinal longitudinal muscle in vitro. Studies on colon revealed that the secretin-evoked response was unaffected by apamin, tetrodotoxin, L-NAME, VIP or PACAP pretreatment; secretin itself caused desensitization. Addition of VIP or PACAP when the secretin-evoked relaxation was maximal evoked a further relaxation suggesting the presence of distinct receptors. Secretin causes relaxation via activation of secretin receptors located on the smooth muscle and not via any of the related VIP/PACAP receptors.

Subject headings

MEDICIN OCH HÄLSOVETENSKAP  -- Klinisk medicin -- Gastroenterologi (hsv//swe)

MEDICAL AND HEALTH SCIENCES  -- Clinical Medicine -- Gastroenterology and Hepatology (hsv//eng)

Keyword

Acetylcholine/pharmacology

Animals

Apamin/pharmacology

Colon/drug effects

Dose-Response Relationship, Drug

Female

Ganglia/metabolism

Gastric Mucosa/metabolism

Ileum/drug effects

Immunohistochemistry

In Situ Hybridization

Intestine, Large/drug effects

Intestine, Small/drug effects

Muscle, Smooth/drug effects

NG-Nitroarginine Methyl Ester/pharmacology

Neuropeptides/pharmacology

Neurotransmitter Agents/pharmacology

Pancreas/metabolism

Pituitary Adenylate Cyclase-Activating Polypeptide

Rats

Rats, Sprague-Dawley

Secretin/biosynthesis

Tetrodotoxin/pharmacology

Vasoactive Intestinal Peptide/pharmacology

Publication and Content Type

art (subject category)

ref (subject category)