[Changes in SR Ca2+-ATPase activity, Ca2+ release and uptake kinetics of diaphragm muscle after different-frequency chronic electrical stimulation of diaphragmatic nerve].
To study adaptation of rabbit diaphragm muscle after different-frequency chronic electrical stimulation, Ca(2+)-ATPase activity and Ca(2+) release-uptake kinetics of sarcoplasmic reticulum (SR) were respectively measured by detecting inorganic phosphorus ion and Furo-2 fluorescence. SR Ca(2+)-ATPase activity of the low-frequency stimulation group was significantly lower than that of the control group (P<0.0l), but it was significantly higher in the high-frequency stimulation group against control (P<0.0l). The kinetics of Ca(2+) release and Ca(2+) uptake was significantly lower in low-frequency group than that of the control (P<0.0l), but the kinetics of Ca(2+) release and Ca(2+) uptake was significantly higher than that of the control (P<0.01). It is thought that different-frequency electrical stimulation induced different adaptative changes in SR Ca(2+)-ATPase activity, and Ca(2+) release and uptake kinetics of rabbit diaphragm muscle.
Zhang
S Y
SY
Institute of Respiratory medicine of Xinqiao Hospital, Third Military Medical University, Chongqing 400037. suiyangzhang@yahoo.com
Liu
G
G
Wang
D L
DL
Guo
X J
XJ
Qian
G S
GS
D000818:Animals; D002118:Calcium / Q000378:metabolism*; D000252:Calcium-Transporting ATPases / Q000378:metabolism*; D003964:Diaphragm / Q000378:metabolism*; D004558:Electric Stimulation; D005260:Female; D008297:Male; D009130:Muscle, Smooth / Q000502:physiology; D010791:Phrenic Nerve / Q000502:physiology*; D011817:Rabbits; D012519:Sarcoplasmic Reticulum / Q000378:metabolism*
D000252:Calcium-Transporting ATPases; D002118:Calcium