Prostaglandin F2 alpha inhibits acidification in H(+)-secreting epithelia.
The role of prostaglandins in the regulation of acidification mechanisms in H(+)-secreting epithelia has been investigated in the abdominal skin of the southern leopard frog, Rana pipiens. Exogenous administration of prostaglandin (PG) E2 and PGF1 alpha (10(-7) M) to the serosal media of paired skins mounted in modified Ussing chambers showed no significant alteration on H+ excretion rates. PGF2 alpha exhibited a dose-dependent inhibition of acidification in both the mucosal and serosal media of animals in normal acid-base states. The ED50 was determined to be 5 X 10(-8) M. Animals placed in an NH4Cl-induced chronic metabolic acidosis demonstrated enhanced H+ excretion from normal which was inhibited by PGF2 alpha (10(-8) M). Frogs treated with ibuprofen (30 mg/kg/day for 3 days) stimulated mucosal acidification to a magnitude similar to the chronic metabolic acidosis animal, and this was inhibited by PGF2 alpha (10(-8) M) during the recovery phase. PGF2 alpha produced effects on both the mucosal proton excretion system and the serosal Na+/H+ exchanger mechanism. PGF2 alpha appears to function in this H(+)-secreting epithelia to maintain a low basal H+ excretion rate and to regulate intracellular pH.
Page
R D
RD
Department of Pharmacology, Texas College of Osteopathic Medicine, Fort Worth.
Yorio
T
T
D000138:Acidosis / Q000139:chemically induced*; D000818:Animals; D015237:Dinoprost / Q000494:pharmacology*; D004347:Drug Interactions; D004848:Epithelium / Q000187:drug effects / Q000378:metabolism; D006859:Hydrogen / Q000378:metabolism*; D006863:Hydrogen-Ion Concentration; D007052:Ibuprofen / Q000494:pharmacology; D011894:Rana pipiens; D012867:Skin / Q000187:drug effects* / Q000378:metabolism
D006859:Hydrogen; D015237:Dinoprost; D007052:Ibuprofen