Table 1.
Basal cardiovascular parameters and effects of the first injection (S1) of anandamide and methanandamide on basal cardiovascular parameters in anaesthetized and pithed rats
| Group | Agonist | Parameter | Units | Basal |
Changes in cardiovascular parameters noticed in |
||
|---|---|---|---|---|---|---|---|
| Phase I | Phase II | Phase III | |||||
| Anaesthetized rats (anaesthesia with urethane, basal DBP brought to 60–70 mmHg when necessary) | Anandamide (n= 32) | MBP | mmHg | 79.8 ± 1.7 | −4.2 ± 1.9 | 21.5 ± 1.4 | −14.1 ± 1.1 |
| SBP | mmHg | 112.0 ± 2.5 | −2.7 ± 0.9 | 17.3 ± 1.3 | −16.6 ± 1.7 | ||
| DBP | mmHg | 62.8 ± 1.5 | −10.5 ± 2.3 | 24.3 ± 1.0 | −15.8 ± 1.0 | ||
| MBF | mL·min−1 | 4.84 ± 0.23 | −0.11 ± 0.04 | 2.82 ± 0.23 | −0.80 ± 0.14 | ||
| RBF | mL·min−1 | 2.86 ± 0.18 | −0.09 ± 0.06 | 1.00 ± 0.09 | −0.50 ± 0.06 | ||
| HR | beats·min−1 | 367.8 ± 9.2 | −56.8 ± 13.1 | NA | NA | ||
| Methanandamide (n= 13) | MBP | mmHg | 78.6 ± 2.8 | −1.2 ± 0.9 | 14.8 ± 1.0 | −13.5 ± 1.7 | |
| SBP | mmHg | 117.3 ± 5.3 | −1.0 ± 0.7 | 11.8 ± 1.5 | −17.3 ± 2.3 | ||
| DBP | mmHg | 61.7 ± 2.4 | −8.0 ± 1.2 | 17.1 ± 1.6 | −13.0 ± 1.4 | ||
| MBF | mL·min−1 | 4.51 ± 0.36 | −0.06 ± 0.04 | 2.21 ± 0.15 | −0.51 ± 0.06 | ||
| RBF | mL·min−1 | 2.74 ± 0.32 | −0.05 ± 0.05 | 0.88 ± 0.10 | −0.43 ± 0.10 | ||
| HR | beats·min−1 | 354.6 ± 20.6 | −29.2 ± 5.5 | NA | NA | ||
| Pithed rats (anaesthesia with urethane, basal DBP brought to 60–70 mmHg, treatment with ruthenium red 3 µmol·kg−1) | Anandamide (n= 21) | MBP | mmHg | 81.1 ± 1.3 | NA | 15.2 ± 1.0 | −12.5 ± 1.1 |
| SBP | mmHg | 95.6 ± 1.7 | NA | 16.1 ± 5.6 | −13.1 ± 1.0 | ||
| DBP | mmHg | 69.2 ± 1.0 | NA | 15.5 ± 1.0 | −12.1 ± 1.4 | ||
| HR | beats·min−1 | 372.3 ± 5.0 | NA | NA | NA | ||
| Pithed rats (anaesthesia with pentobarbitone; treatment with pancuronium 0.8 µmol·kg−1) | Methanandamide (n= 20) | DBP | mmHg | 51.6 ± 1.4 | ND | ND | ND |
| HR | beats·min−1 | 327.6 ± 3.9 | ND | ND | ND | ||
Basal parameters were determined immediately prior to the first i.v. administration (S1) of anandamide or methanandamide. In pentobarbitone-anaesthetized rats basal cardiovascular parameters immediately before the first electrical stimulation are given. Mean ± SEM of the number of rats given in the second column.
DBP, diastolic blood pressure; HR, heart rate; MBF, mesenteric blood flow; MBP, mean blood pressure; NA, not applicable; ND, not determined; RBF, renal blood flow; SBP, systolic blood pressure.