Effects of Prazosin
نویسندگان
چکیده
The left ventricular (LV) and coronary vascular effects of prazosin, a drug that reduces peripheral vascular resistance by blocking postsynaptic a receptors, were examined in conscious dogs. Prazosin, 0.07 mg/kg/mmn i.v. for 7 minutes, induced sustained hypotensive effects for more than 12 hours. The peak effects occurred 3045 minutes after administration. Prazosin increased heart rate by 28 ± 9%, did not change mean coronary blood flow significantly, decreased mean arterial pressure by 15 i 4%, LV enddiastolic diameter by 10 + 2%, LV end-systolic diameter by 8 ± 2%, late diastolic coronary resistance by 22 : 7%, and---LV dP/dt by 9 i 4%. These effects of prazosin were not altered substantially by maintaining heart rate constant with electrical pacing or by pretreatment with ,B-adrenergic blockade. However, after chronic reserpine treatment, prazosin did not reduce either mean arterial pressure or late diastolic coronary resistance. The a-blocking properties of the drug were established when prazosin attenuated pressor responses to
منابع مشابه
Effects of prazosin on coronary and left ventricular dynamics in conscious dogs.
The left ventricular (LV) and coronary vascular effects of prazosin, a drug that reduces peripheral vascular resistance by blocking postsynaptic alpha receptors, were examined in conscious dogs. Prazosin, 0.07 mg/kg/min i.v. for 7 minutes, induced sustained hypotensive effects for more than 12 hours. The peak effects occurred 30-45 minutes after administration. Prazosin increased heart rate by ...
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