Figure 3

Effect of nifedipine on contraction force. Maximum contraction forces of GAS, RF and GLU in proportion to the cross-sectional area of the muscle (white), and the average responses to 1 μM nifedipine solution (grey) are shown. The fatigue control was performed with GAS, RF and GLU in physiological salt solution devoid of nifedipine in order to control the procedure and to rule out the possibility of fatigue. The statistical significance of differences between means of contraction forces before and after the addition of nifedipine solution is shown by levels (*, P < 0.05; ** P < 0.01, paired samples t-test).