Table 1.
Effects of anandamide on action potential parameters in normal rat papillary muscles (n= 6)
| RP (mV) | OS (mV) | APA (mV) | Vmax (Vs−1) | APD50 (ms) | APD90 (ms) | |
|---|---|---|---|---|---|---|
| Control | −82.3 ± 3.9 | 12.0 ± 2.7 | 94.5 ± 4.8 | 70.2 ± 5.8 | 24.6 ± 2.7 | 98.8 ± 5.2 |
| Anandamide (nM) | ||||||
| 1 | −84.6 ± 1.8 | 12.1 ± 3.8 | 96.7 ± 3.1 | 73.3 ± 7.1 | 23.9 ± 3.9 | 96.2 ± 6.6 |
| 10 | −84.5 ± 3.4 | 10.7 ± 2.7 | 95.2 ± 2.0 | 73.3 ± 7.1 | 19.1 ± 2.8**# | 80.7 ± 5.2***## |
| 100 | −86.7 ± 4.3 | 9.2 ± 2.7 | 95.9 ± 4.8 | 70.5 ± 5.9 | 17.5 ± 2.1**##++ | 68.9 ± 5.2***###+++ |
**
P < 0.01,
***
P < 0.001 versus control.
#
P < 0.05,
##
P < 0.01,
###
P < 0.001 versus 1 nM anandamide.
++
P < 0.01,
+++
P < 0.001 versus 10 nM anandamide.
APA, amplitude of action potential; APD50, duration of 50% repolarization; APD90, duration of 90% repolarization; OS, overshoot; RP, resting membrane potential; Vmax, maximal rising velocity of depolarization in phase 0.