M. Mayhew et al., EFFECTIVENESS OF CALORIC RESTRICTION IN PREVENTING AGE-RELATED-CHANGES IN RAT SKELETAL-MUSCLE, Biochemical and biophysical research communications (Print), 251(1), 1998, pp. 95-99
The dihydropyridine receptor (DHPR) and ryanodine receptor (RYR1) are
needed for excitation-contraction coupling in skeletal muscle. Previou
s studies from this laboratory have shown DHPR-RYR1 uncoupling in SS-m
onth-old Fischer 344 x Brown Norway F1 (F344BNF1) rats fed ad libitum.
The purpose of the present study is to determine whether caloric rest
riction prevents age-related impairments in skeletal muscle function a
nd expression of DHPR and RyR1. Bundles of soleus and extensor digitor
um longus (EDL) were studied from rats fed ad libitum and on 60 percen
t caloric restriction. Significant differences were found in peak twit
ch or tetanic tension between the ad libitum and calorie-restricted gr
oups in soleus and EDL muscles. A significant increase in the expressi
on of DHPR and RyR1 was observed in caloric restricted rats. These res
ults show that calorie restriction preserves the mechanical properties
of aging hind-limb skeletal muscle and maintains the level of DHPR an
d RyR1 in aged F344BNF1 rats fed ad libitum. (C) 1998 Academic Press.