title: Role of sodium on H+ excretion in the integument of the leopard frog Rana pipiens.
abstract: 1. The northern leopard frog, Rana pipiens, pipiens, in contrast to the southern leopard frog, Rana pipiens, berlandieri, did not demonstrate any significant H+ excretion across its integument even during a challenge of chronic metabolic acidosis. Likewise, no increase in the number of H+ secreting mitochondria-rich cells were observed in the northern frogs. 2. Under normal acid-base conditions in the southern frogs, H+ excretion was found to be dependent on mucosal sodium concentrations, whereas during chronic metabolic acidosis, H+ excretion was independent of mucosal sodium concentrations, but was amiloride sensitive. 3. High salinity adapted southern frogs, under normal and acidotic conditions, had enhanced H+ excretion rates as compared to the control non-salt adapted frogs. 4. Blood analyses demonstrated that significant acid-base changes were the result of systemic acidosis and not due to salt adaptations. Blood Na+ and K+ concentrations were also efficiently maintained during salt adaptations or chronic metabolic acidosis. 5. The results suggest that H+ excretion in epithelia can be influenced by the sodium transport state of the cell and the systemic acid-base profile. Models are proposed explaining these relationships.
authors.affiliation: Department of Pharmacology, Texas College of Osteopathic Medicine, Fort Worth 76107.
authors.forename: R
authors.initials: R
authors.lastname: Page
authors.forename: L W
authors.initials: LW
authors.lastname: Frazier
authors.forename: T
authors.initials: T
authors.lastname: Yorio
mesh_terms: D000222:Adaptation, Physiological; D000584:Amiloride / Q000494:pharmacology; D000818:Animals; D006863:Hydrogen-Ion Concentration; D066298:In Vitro Techniques; D007474:Ion Exchange; D011522:Protons; D011894:Rana pipiens / Q000097:blood / Q000378:metabolism*; D012867:Skin / Q000187:drug effects / Q000378:metabolism*; D012964:Sodium / Q000378:metabolism*; D012965:Sodium Chloride / Q000008:administration & dosage
chemical_list: D011522:Protons; D012965:Sodium Chloride; D000584:Amiloride; D012964:Sodium