Table 6.
Effect of short-term peroral administration of vehicle, alosetron and tegaserod on MAP, HR, MBF, MVC, CBF and CVC of fasted rats at baseline (before) and after acute i.v. injection of L-NAME
| Treatment and recording period | MAP (mmHg) | HR (beats·min−1) | MBF (µL·min−1) | MVC [µL·min−1 (mmHg)−1] | CBF (PU) | CVC [PU (mmHg)−1] |
|---|---|---|---|---|---|---|
| 25–10 min before L-NAME (vehicle pretreatment) | 77.3 ± 4.23 | 316 ± 11.8 | 16.4 ± 0.74 | 215 ± 16.0 | 196 ± 47.8 | 2.68 ± 0.71 |
| 5–20 min post L-NAME (vehicle pretreatment) | 124 ± 3.41** | 350 ± 10.0** | 7.91 ± 0.81** | 64.3 ± 8.26** | 169 ± 45.7 | 1.38 ± 0.38** |
| 95–110 min post L-NAME (vehicle pretreatment) | 125 ± 2.46** | 365 ± 16.2** | 7.59 ± 0.99** | 60.2 ± 7.48** | 183 ± 43.1 | 1.44 ± 0.33** |
| 25–10 min before L-NAME (alosetron pretreatment) | 77.3 ± 5.90 | 316 ± 24.2 | 14.0 ± 1.76 | 192 ± 30.8 | 349 ± 73.9 | 5.05 ± 1.35 |
| 5–20 min post L-NAME (alosetron pretreatment) | 120 ± 2.50** | 340 ± 10.7 | 8.02 ± 1.63** | 67.3 ± 14.4** | 303 ± 64.1 | 2.57 ± 0.58** |
| 95–110 min post L-NAME (alosetron pretreatment) | 116 ± 5.95** | 328 ± 17.1 | 8.33 ± 1.41** | 73.2 ± 12.9** | 428 ± 123 | 4.01 ± 1.28 |
| 25–10 min before L-NAME (tegaserod pretreatment) | 83.1 ± 5.68 | 340 ± 20.8 | 16.0 ± 1.23 | 199 ± 21.4 | 328 ± 94.4 | 3.94 ± 1.22 |
| 5–20 min post L-NAME (tegaserod pretreatment) | 126 ± 2.88** | 331 ± 10.1 | 8.37 ± 0.68** | 66.5 ± 5.69** | 310 ± 93.2 | 2.39 ± 0.70** |
| 95–110 min post L-NAME (tegaserod pretreatment) | 125 ± 2.28** | 342 ± 9.44 | 7.41 ± 0.89** | 59.6 ± 7.51** | 221 ± 63.4 | 1.74 ± 0.48** |
Rats were pretreated for 7 days by 3 daily IG administrations of vehicle, alosetron (0.3 mg·kg−1) or tegaserod (1 mg·kg−1). The cardiovascular parameters were recorded before and after i.v. injection of L-NAME (0.02 mmol·kg−1) and averaged for the periods indicated. Means ± SEM, n= 7.
P < 0.01 versus pre-injection (one way anova for repeated measures followed by the Bonferroni test).
CBF, colonic blood flow; CVC, colonic vascular conductance; HR, heart rate; L-NAME, N-nitro-L-arginine methylester; MAP, mean arterial blood pressure; MBF, mesenteric blood flow; MVC, mesenteric vascular conductance; PU, perfusion unit.