ROLE OF THE MEMBRANE EXCITABILITY IN MUSCLE FATIGUE
PART I
OBJECTIVES (I and II)• Methodology:
• Electrophysiology: resting Em and action potential • Measurement of ion channel activity
• Control of membrane excitability during muscle activity:
• Role of ions (Na+, K+ and Cl-)• Role of Cl- and K+ channels
INTRODUCTION
Lännergren and Westerblad, 1991
Lännergren and Westerblad, 1991
CAFFEINE
Lännergren and Westerblad, 1991
PLA: placeboCIT: ingestion of sodium citrate to create an alkalosis
PLA: placebo
CIT: ingestion of sodium citrate to create an alkalosis
PLA: placebo
CIT: ingestion of sodium citrate to create an alkalosis
DISCUSSION
y = yo e-bx
yo= V/I = Rin (input resistance, from intercept)
= 1/b (length constant, from slope)
rm = 2 Rin
EDL
SOLEUS