Related Experiment Video
Updated: Jun 19, 2026
Mucin Agarose Gel Electrophoresis: Western Blotting for High-molecular-weight Glycoproteins
Published on: June 14, 2016
Spasmolytic polypeptide: a trefoil peptide secreted by rat gastric mucous cells
G P Jeffrey1, P S Oates, T C Wang
1Gastrointestinal Unit, Massachusetts General Hospital, Boston.
Background/Aims:
Spasmolytic polypeptide (SP) is a trefoil peptide expressed in the digestive tract. This study aimed to determine the structure and distribution of SP expression in the rat gastrointestinal tract.
Methods:
The structure of rat SP was determined from the sequence of complementary DNAs isolated from antral RNA. SP gene expression was localized by Northern blotting and in situ hybridization in the adult and fetal rat digestive tract. Expression of the SP peptide was localized by immunocytochemistry and Western blot analysis.
Results:
SP messenger (m)RNA was found predominantly in the stomach with highest expression in the antrum. High levels of SP mRNA were expressed in the fetal stomach before gastrin and somatostatin expression. Surprisingly, SP mRNA and peptide did not colocalize in the gastric mucosa, SP mRNA being superficial to SP peptide immunoreactivity throughout the gastric mucosa. Abundant SP immunoreactivity was seen in the lumen of the gastric glands and the mucus layer adherent to the gastric mucosa, indicating luminal secretion.
Conclusions:
In the rat, SP is a peptide secreted predominantly from antral mucous cell. The high concentrations of SP in the adherent gastric mucus layer (approximately 10 mumol/L) suggest that SP functions as a structural peptide rather than a regulatory peptide.
More Related Videos
09:16Mixed Primary Cultures of Murine Small Intestine Intended for the Study of Gut Hormone Secretion and Live Cell Imaging of Enteroendocrine Cells
Published on: April 20, 2017
04:18Enhanced Spatial Mapping of Mouse Gastric Muscle Layers Using a Modified Swiss Roll Technique
Published on: November 25, 2025
Related Concept Videos
01:40Hormonal Regulation
01:20Drugs for Peptic Ulcer Disease: Prostaglandin Analogs as Mucosal Protective Agents
Non-steroidal anti-inflammatory drugs (NSAIDs) can induce peptic ulcers by inhibiting cyclooxygenase, decreasing...
01:25Hormones Secreted by the Stomach
Each of these hormones secreted by different enteroendocrine cells plays a unique role in digestion. Here are a few examples:
01:26Gastric Phase of Digestion
When food enters the stomach, it stretches the stomach walls and activates stretch receptors. This triggers local reflexes of the enteric nervous system, mediated through the myenteric plexus. These...
01:29Intestinal Phase of Digestion
The arrival of the chyme in the small intestine distends the duodenum, which triggers the enterogastric reflex. This distension...
01:25Mucosal Barrier of the Stomach
Within parietal cells, carbonic acid is first formed through the reaction of water and carbon dioxide. The dissociation of carbonic acid releases bicarbonate and hydrogen ions. The bicarbonate...