The role of aldosterone in water and electrolyte transport across the colonic epithelium of the lizard, Gallotia galloti.
1. The effects of D-aldosterone on the electrical properties and ionic transport have been analysed (in vitro) in the colonic epithelium of the lizard, Gallotia galloti. 2. The injection of 30 g of D-aldosterone induced a significant rise of plasma aldosterone concentration, sustained for 4 hr after administration. 3. Intraperitoneal injections of D-aldosterone caused a slight reduction of transmural potential difference (PD) and short-circuit current (Isc). 4. Net absorption of Na+ across the colon from aldosterone-treated lizards did not increase when compared to colon from normal lizards. Cl- absorption was increased in treated lizards. 5. Addition of mucosal barium to treated tissues brought about a sustained increase of PD and Isc. 6. The absorption of fluid in normal lizards was reversed to fluid secretion in treated lizards. 7. The effects of D-aldosterone on lizard colon are compared with those reported for the colon of mammals and birds.
Diaz
M
M
Departamento de Fisiologia Animal, Facultad de Biologia, Universidad de la Laguna, Canary Islands, Spain.
Lorenzo
A
A
Badia
P
P
Gomez
T
T
D000450:Aldosterone / Q000097:blood / Q000494:pharmacology*; D000818:Animals; D001693:Biological Transport, Active / Q000187:drug effects; D002712:Chlorides / Q000378:metabolism; D003106:Colon / Q000187:drug effects* / Q000378:metabolism; D004594:Electrophysiology; D004848:Epithelium / Q000187:drug effects / Q000378:metabolism; D005260:Female; D066298:In Vitro Techniques; D008116:Lizards / Q000378:metabolism*; D008297:Male; D012964:Sodium / Q000378:metabolism; D014882:Water-Electrolyte Balance / Q000187:drug effects*
D002712:Chlorides; D000450:Aldosterone; D012964:Sodium