Effect of the histamine-2 agonist impromidine on stem cell proliferation of rat oxyntic mucosa.
BACKGROUND
The trophic effect of gastrin on the histamine-containing enterochromaffin-like cell is pronounced but on the stem cell of the oxyntic mucosa it is only modest. In the rat, gastrin stimulates acid secretion mainly by releasing histamine from enterochromaffin-like cells. This study was designed to test the hypothesis that the trophic effect of gastrin on stem cells is also mediated by histamine released from the enterochromaffin-like cell.


METHODS
We stimulated rats with the histamine-2 agonist impromidine. Impromidine, 0.2 mg/h, was given for 2 days by subcutaneously implanted osmotic minipumps, and the trophic effect on stem cells was assessed by incorporation of tritiated thymidine.


RESULTS
The plasma gastrin concentrations were 33.9 (9.4) pM and 27.3 (6.0) pM, and the stem cell labelling index values were 5.92 (1.94) and 8.09 (3.78) in the controls and impromidine-stimulated animals, respectively (mean value (SD)). These differences were not statistically significant.


CONCLUSIONS
The present study provides no evidence that histamine-2 receptors mediate a trophic effect on the stem cell of the rat oxyntic mucosa.
Brenna
E
E
Institute of Cancer Research, University Hospital, Trondheim, Norway.
Tielemans
Y
Y
Kleveland
P M
PM
Sandvik
A K
AK
Willems
G
G
Waldum
H L
HL
D000818:Animals; D002455:Cell Division / Q000187:drug effects; D005260:Female; D005755:Gastrins / Q000097:blood; D017442:Histamine Agonists / Q000494:pharmacology*; D017446:Impromidine / Q000494:pharmacology*; D010295:Parietal Cells, Gastric / Q000166:cytology / Q000187:drug effects*; D051381:Rats; D017207:Rats, Sprague-Dawley; D011970:Receptors, Histamine H2 / Q000502:physiology; D013234:Stem Cells / Q000166:cytology / Q000187:drug effects*; D013268:Stimulation, Chemical
D005755:Gastrins; D017442:Histamine Agonists; D011970:Receptors, Histamine H2; D017446:Impromidine