1H-NMR and (31)P-NMR analysis of energy metabolism of quiescent and motile turbot (Psetta maxima) spermatozoa

31P-NMR and (1)H-NMR were used to monitor changes of several compounds with high-energy bonds and metabolites prior to and after the initiation of motility of turbot spermatozoa (Psetta maxima). The obtained (31)P-NMR spectra revealed the presence of phosphomonoesters, phosphodiester, intracellular inorganic phosphate (Pi), phosphocreatine (PCr), and free nucleotide triphosphate. Following the activation of motility, the di- and tri-phosphate nucleotides, PCr, phosphomonoesters levels dropped while Pi levels increased. A significant increase of lactate was also seen at the end of the swimming phase. The compositions of seminal fluid and urine were also determined. Lipoproteins, formic acid, amino acid, and citric acid were detected in seminal fluid. Dimethyl amine, trimethylamine, and trimethylamine oxyde were found in urine. These data suggest that at least a part of the energy required during the swimming phase results from anaerobic fermentation and oxidative phosphorylation. J. Exp. Zool. 286:513-522, 2000.