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Updated: Oct 12, 2026

Exploring Arterial Smooth Muscle Kv7 Potassium Channel Function using Patch Clamp Electrophysiology and Pressure Myography
Published on: September 14, 2012
Intrinsic pressor activity of midaglizole, an alpha-2 adrenoceptor antagonist, in pithed rats
M Hirohashi1, K Tamura, A Akashi
1Research Institute, Daiichi Pharmaceutical Co., Ltd., Tokyo, Japan.
Abstract:
Midaglizole (3 and 30 mg/kg, i.v.) increased blood pressure in pithed rats. The pressor response was not inhibited by intravenous prazosin (0.3 mg/kg), yohimbine (1 mg/kg), ketanserin (1 mg/kg) or diphenhydramine (5 mg/kg). Diltiazem (1 mg/kg) antagonized the hypertension. Idazoxan (10 mg/kg) also increased blood pressure, and the pressor response was inhibited by prazosin, but not by yohimbine. These results suggest that the vascular effect of midaglizole is due to a mechanism different from that of idazoxan.
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