Structure, function, and long-term maintenance of the isolated turtle colon.
We describe the 5-day maintenance of sacs of turtle colonic mucosa in enriched bathing solutions. The mean maximum transepithelial potential difference (PD) developed by the sacs in Ringer solution enriched with tissue-culture medium and gassed with 95% air-5% CO2 was 126 mV at 24 hours. Lower values were observed in other solutions. The PD of 24-hour sacs was partially or totally inhibited by ouabain, replacement of Na by choline in mucosal bathing fluids, or removal of Ca from serosal bathing fluids. The sacs transported Na in excess of H2O forming a dilute mucosal solution. The response of four different sac preparations (normally oriented or everted, and stripped normally oriented or everted) to long incubation were compared. Stripped normally oriented tissue developed the highest PD and maintained the lowest water content. The morphology of fresh and long-incubated tissue was examined. This investigation demonstrates that the turtle colon can be maintained in vitro for long periods, and it provides information on the morphology and physiology of this tissue.
D000818:Animals; D003106:Colon / Q000166:cytology / Q000502:physiology*; D066298:In Vitro Techniques; D007413:Intestinal Mucosa / Q000166:cytology / Q000378:metabolism; D010042:Ouabain / Q000494:pharmacology; D011188:Potassium / Q000494:pharmacology*; D012964:Sodium / Q000494:pharmacology; D014021:Tissue Preservation / Q000379:methods; D014426:Turtles / Q000033:anatomy & histology / Q000502:physiology*
D010042:Ouabain; D012964:Sodium; D011188:Potassium