Increasing mRNA levels of the Na/K pump β1 subunit in the skeletal muscles stimulated with low frequency pulse wave

Abstract

We investigated the effect of low frequency pulse wave stimulation (LFPWS) on transcription levels of Na/K pump in skeletal muscle cells. Bilateral anterior tibial muscles of an F344 rat were pierced by two needles respectively under anesthesia with isoflurane. LFPWS (5 V, 0.7 msec) was given only to the right-side muscle for 1 hour at 30 ppm or 400 ppm. Those muscles were collected followed by total RNA extraction. The mRNA levels of both α1 and β1 subunits were measured by reverse transcription-quantitative PCR. The mRNA level of α1 subunit did not change significantly between LFPWS-treated and untreated muscles either at 30 ppm (n=7) or 400 ppm (n=7). The level of β1 subunit did not change by LFPWS at 30 ppm (n=7), while that increased 1.5-fold at 400 ppm significantly (P<0.05, n=6). Our study demonstrated relatively selective upregulation of β1 subunit transcription induced by LFPWS on the skeletal muscles.