Adrenergic supersensitivity in parkinsonians with orthostatic hypotension.

摘要: . The adrenergic status was studied through evaluation of platelet α2-adrenoceptor number ([3H]-yohimbine binding sites), plasma catecholamine levels and blood pressure response to noradrenaline infusion in three groups subjects (1) Parkinsonians with orthostatic hypotension; (2) without (3) control subjects. In hypotension, systolic diastolic pressures significantly (P < 0.05) decreased from 144 pM 9 76 6 mmHg the lying position 95 12 60 7 after 5 min standing. these patients, were low (62 11 pg ml-1, when compared controls (219 13 ml-1) whereas no difference noticed hypotension (195 14 ml-1). dose required for a 25 increase 0.01) lower (019 0.03 μg kg-1) (0.86 0.11 or (0.68 0.l kg-1). Platelet x2-adrenoceptor higher (313 52 fmol mg-1 protein) than (168 (175 4 change Kd. This study demonstrates that patients Parkinson's disease, is associated an both vascular sensitivity number. These observations suggest existence α-adrenergic supersensitivity noradrenaline.