Table 2.
Effect of charybdotoxin (ChTx) or activation of the 5-HT1 receptor on the concentration–response curve for U46619-induced contraction in the absence and presence of the T-type voltage-operated calcium channel blockers mibefradil and NNC550396
| pEC50 | Rmax | n | |
|---|---|---|---|
| U46619 (control) | 7.29 ± 0.07 | 135.7 ± 5.4 | 5 |
| U46619 + 5-HT + ritanserin | 7.51 ± 0.10 | 197.9 ± 10.6* | 4 |
| U46619 + 5-HT + ritanserin + mibefradil | 7.33 ± 0.10 | 126.7 ± 6.2# | 4 |
| U46619 (control) | 7.37 ± 0.09 | 129.6 ± 6.1 | 5 |
| U46619 + ChTx | 7.65 ± 0.06* | 178.2 ± 5.4* | 5 |
| U46619 + ChTx + mibefradil | 7.41 ± 0.08§ | 112.1 ± 4.4§ | 4 |
| U46619 + ChTx + NNC550396 | 7.49 ± 0.08§ | 116.7 ± 4.7§ | 4 |
Significantly different (0.00 < P < 0.05, anova with Tukey post test)
*
from U46619 control;
#
from U46619 with 5-HT1 receptor activation;
§
from U46619 in the presence of ChTx. n= number of arteries from different animals.