Effect of desipramine on spontaneous arterial pressure oscillations in the rat.
There has been no previous report on the effect of the noradrenaline uptake inhibitor desipramine on short-term variability of arterial pressure. Mean arterial pressure was recorded in 9 conscious resting rats during 4 consecutive 30-min periods: (1) under baseline conditions, (2) after desipramine administration (2 mg/kg i.v., followed by 1 mg/kg every hour), then after (3) cardiac autonomic blockade with methylatropine and atenolol, and (4) alpha-adrenoceptor blockade with phentolamine. Fast Fourier transform analysis was applied to beat-to-beat data after resampling at 10 Hz of consecutive 205-s time series. Desipramine did not change the mean level and overall variability of mean arterial pressure. However, spectral power in the mid-frequency (0.3-0.5 Hz) band containing the Mayer waves was reduced by more than 80%, and power in the low-frequency (0.05-0.2 Hz) band was enhanced by approximately 50%, especially due to the appearance of a major oscillation centred at 0.095 +/- 0.005 Hz. This slow oscillation was further enhanced after cardiac autonomic blockade and was abolished after alpha-adrenoceptor blockade. In conclusion, desipramine profoundly alters short-term arterial pressure variability in resting rats, mainly by shifting vasomotor waves from 0.4 to 0.1 Hz. Desipramine may prove a valuable pharmacological tool to study the dynamic aspects of arterial pressure control.
Bertram
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Département de Physiologie et Pharmacologie Clinique, CNRS ESA 5014, Faculté de Pharmacie, Lyon, France. bertram@rockefeller.univ-lyon1.fr
Barrès
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Julien
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C
D018759:Adrenergic Uptake Inhibitors / Q000494:pharmacology*; D000317:Adrenergic alpha-Antagonists / Q000494:pharmacology; D000818:Animals; D001794:Blood Pressure / Q000187:drug effects* / Q000502:physiology; D003891:Desipramine / Q000494:pharmacology*; D005583:Fourier Analysis; D006329:Heart Conduction System / Q000187:drug effects; D006339:Heart Rate / Q000187:drug effects / Q000502:physiology; D008297:Male; D010646:Phentolamine / Q000494:pharmacology; D051381:Rats; D017207:Rats, Sprague-Dawley
D018759:Adrenergic Uptake Inhibitors; D000317:Adrenergic alpha-Antagonists; D003891:Desipramine; D010646:Phentolamine