AJP - Cell Physiology, Vol 253, Issue 2 C205-C209, Copyright © 1987 by American Physiological Society

ARTICLES

Actin synthesis rate and mRNA level increase during early recovery of atrophied muscle

P. R. Morrison, G. W. Muller and F. W. Booth

The purpose of this study was to correlate actin synthesis rate and alpha-actin mRNA level in the gastrocnemius-plantaris muscles of limbs during their recovery from 7 days of immobilization in 200- to 280-g female rats. The fractional synthesis rate of actin in control muscle was 1%/day. Actin synthesis rate was 33% of control level at the 7th day of hindlimb immobilization, returned to control value at the 2nd recovery day, and was three times higher than control on the 4th day of recovery. The alpha-actin mRNA was 53% of control at the 7th day of immobilization, and its increase during the 1st 2 recovery days paralleled the increase in actin synthesis rate; this suggests that pretranslational mechanisms caused the initial increase in actin synthesis. Further increases in actin synthesis from the 2nd to the 4th day appear to be under translational control, since actin synthesis was 300% of control on the 4th recovery day and alpha-actin mRNA was only 128% of control.

This article has been cited by other articles:

				X.-Y. Han, W. Wang, R. Myllyla, P. Virtanen, J. Karpakka, and T. E. S. Takala mRNA levels for alpha -subunit of prolyl 4-hydroxylase and fibrillar collagens in immobilized rat skeletal muscle J Appl Physiol, July 1, 1999; 87(1): 90 - 96. [Abstract] [Full Text] [PDF]

				S. Welle, K. Bhatt, and C. A. Thornton Stimulation of myofibrillar synthesis by exercise is mediated by more efficient translation of mRNA J Appl Physiol, April 1, 1999; 86(4): 1220 - 1225. [Abstract] [Full Text] [PDF]