title: Metabolic requirements for anaerobic active Cl and Na transport in the bullfrog cornea.
abstract: In the bullfrog cornea, the relationships between the rates of aerobic and anaerobic glycolysis and active Cl and Na transport were studied. In NaCl Ringer (glucose-free), the short-circuit current (SCC) declined much more slowly under aerobic than under anaerobic conditions. The aerobic lactate effluxes in glucose-free and glucose-rich NaCl Ringer were 0.08 and 0.23 micromol/h.cm2, respectively. The transition to anoxia caused these values to increase significantly and was accompanied by depletion of endogenous glycogen in glucose-free Ringer. In Na2SO4 Ringer, amphotericin B (10(-5) M) stimulation of the aerobic SCC was not dependent on the presence of glucose but under anoxia, SCC stimulation required glucose. In Na2SO4 (glucose-rich) Ringer, amphotericin B stimulated the aerobic lactate efflux from 0.26 to 0.36 mumol/h.cm2 and anoxia increased it to 0.55 micromol/h.cm2. In NaCl Ringer, the addition of either 0.5 mM adenosine or 1 mM ATP with 26 mM glucose restored the anaerobic-inhibited SCC and lactate efflux of glucose-depleted corneas. The results show that the reactions of glycolysis are a sufficient energy source for supporting active Na and Cl transport.
mesh_terms: D000666:Amphotericin B / Q000494:pharmacology; D000693:Anaerobiosis; D000818:Animals; D001693:Biological Transport, Active; D002712:Chlorides / Q000378:metabolism*; D003315:Cornea / Q000378:metabolism*; D004734:Energy Metabolism; D005947:Glucose / Q000494:pharmacology; D006019:Glycolysis; D000860:Hypoxia; D066298:In Vitro Techniques; D011892:Rana catesbeiana / Q000378:metabolism; D012964:Sodium / Q000378:metabolism*
chemical_list: D002712:Chlorides; D000666:Amphotericin B; D012964:Sodium; D005947:Glucose