Glycolytic, pentose-phosphate shunt and transaminase enzymes in gastrocnemius muscle, liver, heart, and brain of two mouse mutants, 129 J-dy and A2g-adr, with abnormal muscle function.

Aldolase and phosphoglycerate kinase activity were markedly reduced in muscle from two mouse mutants, 129 J-dy and A2G-adr, with abnormal muscle development. The pentose-phosphate shunt enzymes, glucose-6-phosphate dehydrogenase and 6-phosphogluconate dehydrogenase, were both greatly increased in the gastrocnemius of 129 J-dy mice, but only the former was slightly increased in A2G-adr muscle. Alanine and aspartate aminotransferase activities were normal or low in 129 J-dy muscle but increased to approximately 200% in A2G-adr muscle. Liver from 129 J-dy mice showed increased activity of glucose-6-phosphate dehydrogenase. These findings are compatible with the well-recognised lipid involvement in the 129 J-dy mutant but indicate that an abnormality of amino acid metabolism in relation to energy supply is probably more important in the A2G-adr mutant.