INTRACELLULAR PH OF MUSCLE AND TEMPERATURE - INSIGHT FROM IN-VIVO P-31 NMR MEASUREMENTS IN A STENOTHERMAL ANTARCTIC TELEOST (HARPAGIFER ANTARCTICUS)

1. Intracellular pH (pH(i)) of white (fast, glycolytic) muscle in the Antarctic teleost Harpagifer antarcticus at 1 degrees C was 7.36 +/- 0 .07 (mean +/- s.e., n = 6), as measured by P-31 NMR. 2. H. antarcticus pH(i) and a compilation of published data indicate that the overall r elationship between pH(i) and temperature in glycolytic muscle is biph asic, with pH(i) relatively independent of temperature in the range 0- 17 degrees C and inversely proportional to temperature above 17 degree s C. 3. The data do not support the suggestion that pH(i)approximate t o pN across temperatures, nor is the data consistent with alphastat re gulation of pH(i). (C) 1998 Elsevier Science Ltd. All rights reserved.