The effect of branched chain amino acids on proteosynthesis in skeletal muscles of japanese quail during ontogenesis

Abstract

We studied the influence of branched chain amino acids on the muscle proteosynthesis of Japanese quail during ontogenesis. We used in vitro incubation of these muscles: musculus extensor metacarpalis radialis (EMR) – wing muscle, musculus ambiens (MA) – leg muscle. The incorporation of ¹⁴C-tyrosine into the individual protein fractions was evaluated. Influences of valine, leucine and isoleucine on proteosynthesis on day 14, 28 and 53 of life of Japanese quails were compared. Different patterns of individual protein fractions were detected. During ontogenesis, in the MA the number of fractions remained unchanged while in the EMR it differed. Four fractions with molecular weight 200–1 000 kDa present on day 14 and 28 were absent on day 53. A new fraction over 200 kDa was detected on day 53. The ¹⁴C-tyrosine incorporation after leucine treatment was enhanced only in the MA of 28 days old quails. The protein content in the EMR decreased (50%) in several fractions. The addition of valine had no effect in the MA while in the EMR the protein content decreased in 14 and 28 days old quails. The incorporation of ¹⁴C-tyrosine was decreased by the influence of isoleucine in the EMR of 28 and 53 days old quails, in the MA only in 28 days old birds. We assume that the effect of regulatory amino acids on proteosynthesis depends both on muscle type and on the age of Japanese quail.