[Effects of chronic administration of moxonidine in hypertensive rats SHR-SP]

Study of the hemodynamic response (arterial pressure and heart rate) by radio- and telemetric techniques in stroke-prone hypertensive rats (SHR-SP) aged 6-7 months showed that a chronic oral administration of moxonidine at a daily dose of 2 and 10 mg/kg) leads to hypotension (7 +/- 3 and 21 +/- 5%, respectively) and bradycardia (5 +/- 1 and 14 +/- 5%, respectively). The moxonidine administration at a greater dose violated the circadian heart rate profile, reduced the motor activity of rats by 34 +/- 15%, and showed a drug dependence syndrome in the heart rate (but not in the arterial pressure). It is concluded that moxonidine administration at large doses may give rise to side effects.