The extent of intracellular acidification during anoxia in the catch muscles of two bivalve molluscs

Abstract

AbstractIntracellular pH (pHi) changes during anoxia in in vitro preparations of the posterior adductor muscle of the blue mussel Mytilus edulis and the byssus retractor muscle of the ribbed mussel Geukensia demissa were observed using phosphorus nuclear magnetic resonance spectrometry. During 12 h of experimental anoxia, the pHi in M. edulis muscles fell from 6.96 to 6.70. Over the same time period, the pHi in G. demissa muscle fell from 6.95 to 6.56. The relatively small degree of intracellular acidification probably reflects low rates of anaerobic energy metabolism in these muscles. However, the degree of pHi change may be sufficient to have important regulatory effects on energy metabolism in catch muscle.