Distribution of Myosin Attachment Times Predicted from Viscoelastic Mechanics of Striated Muscle

作者：Palmer Bradley M^*; Wang Yuan; Miller Mark S

来源：Journal of Biomedicine and Biotechnology, 2011, 592343.

DOI：10.1155/2011/592343

We demonstrate that viscoelastic mechanics of striated muscle, measured as elastic and viscous moduli, emerge directly from the myosin crossbridge attachment time, t(att), also called time-on. The distribution of tatt was modeled using a gamma distribution with shape parameter, p, and scale parameter, beta. At 5mM MgATP, beta was similar between mouse alpha-MyHC (16.0 +/- 3.7ms) and beta-MyHC (17.9 +/- 2.0ms), and p was higher (P < 0.05) for beta-MyHC (5.6 +/- 0.4 no units) compared to alpha-MyHC (3.2 +/- 0.9). At 1mM MgATP, p approached a value of 10 in both isoforms, but beta rose only in the beta-MyHC (34.8 +/- 5.8ms). The estimated mean t(att) (i.e., p beta product) was longer in the beta-MyHC compared to alpha-MyHC, and became prolonged in both isoforms as MgATP was reduced as expected. The application of our viscoelastic model to these isoforms and varying MgATP conditions suggest that l(att) is better modeled as a gamma distribution due to its representing multiple temporal events occurring within t(att) compared to a single exponential distribution which assumes only one temporal event within t(att).

• 出版日期2011