Collecting and paramuscular venules in glandular mucosa of rat stomach.
Blood from the rat gastric mucosa is drained by collecting venules running from the subepithelial layer towards the lamina muscularis mucosae. Details of their structure were studied in translucent, flat strips of the glandular stomach, in thick sections of glandular mucosa cleared in mineral oil and in semi-thin plastic sections. The number and dimensions of collecting venule outlets revealed in flat strips of gastric mucosa increased after administration of atropine and papaverine and intravital ligation of the portal vein in comparison with that of intact animals or animals with intravitally ligated portal vein but without administration of relaxing agents. In hyperemic mucosa short venules running parallel to the lamina muscularis mucosae (paramuscular venules) and draining collecting venules were distinctly visible. Saccular outlets equipped with triangular protrusions usually intervened between these vessels, probably directing blood flow. Collecting venules were straight, curved, extended or two-armed. Furthermore, numerous collecting venules contained circumscribed dilatations (sacculi) connected with the lumen of the collecting venule. Connection of paramuscular and submucosal veins occurred within the muscularis mucosae. Thus, contraction of the muscularis mucosae might control the outflow of venous blood from the gastric mucosa. Conceivably, alternate contraction and relaxation of muscularis mucosae could cause expansion and collapse of collecting venules which, in turn, would facilitate the movement of glandular content to the surface of the stomach and/or movement of interstitial fluid between cells.
Moskalewski
Stanislaw
S
Department of Histology, Medical University of Warsaw, Poland. smosk@ib.amwaw.edu.pl
Biernacka-Wawrzonek
Dorota
D
Klimkiewicz
Justyna
J
Zdun
Rafal
R
D000818:Animals; D001285:Atropine / Q000494:pharmacology; D005260:Female; D005753:Gastric Mucosa / Q000098:blood supply*; D008297:Male; D009130:Muscle, Smooth / Q000098:blood supply; D010208:Papaverine / Q000494:pharmacology; D011169:Portal Vein / Q000502:physiology; D051381:Rats; D017208:Rats, Wistar; D013270:Stomach / Q000098:blood supply*; D014665:Vasodilator Agents / Q000494:pharmacology; D014699:Venules / Q000166:cytology* / Q000187:drug effects
D014665:Vasodilator Agents; D001285:Atropine; D010208:Papaverine