Ambulatory Cardiovascular Activities in L-NAME-Treated Mice

摘要: Objective: High blood pressure (BP) is a dominant risk factor in cardiovascular diseases. An experimental model of nitric oxide synthase (NOS) inhibitor induced hypertension was developed to study some etiologic mechanisms parameters. Methods: Cardiovascular rhythm characteristics were documented mice following the N-omega-nitro-L-arginine- methyl-ester (L-NAME)-treatment (Rx). Radio-telemetered BP, heart rate (HR), and locomotor activity (LA) measured every 4 min for 5 days before 14 after Rx. Data converted into an hourly average analyzed by linear least square rhythmometry. Results: L-NAME-Rx increased systolic BP (SBP) significantly without significant changes diastolic markedly reduced HR: SBP (mm Hg) 143.4 ± 0.6 versus 148.9 0.4, P <0.0001; HR (beat/min): 552.13 2.7 vs. 481 1.8, <0.0001, with depleted amplitude. variations mainly during night time, while almost time-point comparison throughout 24-h span. Although overall LA not changed L-NAME-Rx, noted, especially when light off at 18:00 hour through midnight (P <0.0001), opposite result observed noon this nocturnal animal <0.005), decreased amplitude <0.01). Interestingly, we observe contradicted other reports. Conclusion: The results suggest that NOS blockade may impair autonomic adaptations arterial baroreflex integration, resulting vascular tone systole, but end diastole relaxed cardiac tonus.