Muscle fiber conduction velocity and muscle fiber composition of rat hindlimb muscle.
- VernacularTitle:ラット下肢筋の筋線維伝導速度と筋線維組成
- Author:
SATOSHI MATSUNAGA
;
TSUGUTAKE SADOYAMA
;
TOMOHIRO NAKAMURA
;
SHIGERU KATSUTA
- Publication Type:Journal Article
- Keywords:
Muscle fiber conduction velocity;
Fiber composition;
Rat;
Electrostimulation
- From:Japanese Journal of Physical Fitness and Sports Medicine
1992;41(1):63-69
- CountryJapan
- Language:Japanese
-
Abstract:
To investigate whether muscle fiber conduction velocity reflects muscle fiber type, we studied the extensor digitorum longus (EDL) and soleus (SOL) muscle in 7 male rats aged 12 weeks. Muscle fiber conduction velocity was measured with a surface electrode array during stimulated contraction and calculated from the delay between two action potentials along muscle fibers for a given inter-electrode distance. Conduction velocity in the EDL (2.71±0.50 m/s) was significantly higher (p<0.05) than that in the SOL (2.14±0.34 m/s) . Fiber type, fiber area and fiber diameter were determinated by myosin ATPase staining and NADH-tetrazolium reductase staining. Muscle fiber composition of the EDL and SOL was 94.6±1.8 and 14.8±4.3% FT fibers, respectively, and mean muscle fiber diameter was 62.7±6.2 pm and 79.2±7.8pm, respectively, that of the EDL being significantly smaller (p<0.01) than that of the SOL. It was suggested that individual differences in conduction velocity were caused by differences in muscle fiber composition rather than differences in muscle diameter.
