Quantification of myosin heavy chain isoform in porcine muscle using an enzyme-linked immunosorbent assay

The objective of this study was to develop an indirect enzyme-linked immunosorbent assay (ELISA) to quantify the relative abundance of the myosin heavy chain (MyHC) isoforms in porcine muscle. Longissimus muscle samples were taken from halothane positive (HAL+) and negative (HAL-) pigs and subjected to ELISA using newly generated and commercially available myosin monclonal antibodies (mAbs). Muscle of HAL+ pigs possessed less type I (P <0.01) and IIA (P<0.1), and more type IIB MyHC (P <0.01) than muscle of HAL- pigs. Abundance of IIX MyHC content was negatively correlated (P < 0.0001) to the amount of IIB MyHC in porcine muscle. These data show indirect ELISA can be used to detect genotype differences in muscle MyHC content, and it provides a rapid, sensitive method for determining muscle fiber type in porcine skeletal muscle. Furthermore, these data suggest that the proportion of glycolytic muscle fibers increases at the expense of oxidative fibers.