title: Side-effects of L-dopa on venous tone in Parkinson's disease: a leg-weighing assessment.
abstract: In the present study, the effects of L-dopa treatment on cardiovascular variables and peripheral venous tone were assessed in 13 patients with Parkinson's disease (PD) with Hoehn and Yahr stages 1-4. Patients were investigated once with their regular treatment and once after 12 h of interruption of L-dopa treatment. L-Dopa intake significantly reduced systolic and diastolic blood pressure, heart rate and plasma noradrenaline and adrenaline in both the supine and upright (60 degrees ) positions. A significant reduction in stroke volume and cardiac output was also seen with L-dopa. The vascular status of the legs was assessed through thigh compression during leg weighing, a new technique developed in our laboratory. Healthy subjects were used to demonstrate that this technique provided reproducible results, consistent with those provided by strain gauge plethysmography of the calf. When using this technique in patients with PD, L-dopa caused a significant lowering of vascular tone in the lower limbs as shown, in particular, by an increase in venous distensibility. Combined with the results of the orthostatic tilting, these findings support that the treatment-linked lowering of plasma noradrenaline in patients with PD was concomitant with a significant reduction in blood pressure, heart rate and vascular tone in the lower limbs. These pharmacological side-effects contributed to reduce venous return and arterial blood pressure which, together with a lowered heart rate, worsened the haemodynamic status.
authors.affiliation: Physiologie, Faculté de Médecine and UPRES EA 3920 - IFR 133, Université de Franche Comté, F-25030 Besançon, France.
authors.forename: Jean-Pierre
authors.initials: JP
authors.lastname: Wolf
authors.forename: Malika
authors.initials: M
authors.lastname: Bouhaddi
authors.forename: Francis
authors.initials: F
authors.lastname: Louisy
authors.forename: Andrei
authors.initials: A
authors.lastname: Mikehiev
authors.forename: Laurent
authors.initials: L
authors.lastname: Mourot
authors.forename: Sylvie
authors.initials: S
authors.lastname: Cappelle
authors.forename: Fabrice
authors.initials: F
authors.lastname: Vuillier
authors.forename: Pierre
authors.initials: P
authors.lastname: Andre
authors.forename: Lucien
authors.initials: L
authors.lastname: Rumbach
authors.forename: Jacques
authors.initials: J
authors.lastname: Regnard
mesh_terms: D000328:Adult; D000368:Aged; D000978:Antiparkinson Agents / Q000009:adverse effects*; D001794:Blood Pressure / Q000187:drug effects; D002302:Cardiac Output / Q000187:drug effects; D015259:Dopamine Agents; D004837:Epinephrine / Q000097:blood; D005260:Female; D006339:Heart Rate / Q000187:drug effects; D006801:Humans; D007866:Leg / Q000098:blood supply* / Q000473:pathology; D007980:Levodopa / Q000009:adverse effects*; D008297:Male; D008875:Middle Aged; D009638:Norepinephrine / Q000097:blood; D009929:Organ Size / Q000187:drug effects; D010300:Parkinson Disease / Q000097:blood / Q000188:drug therapy* / Q000503:physiopathology; D010991:Plethysmography; D011187:Posture; D015203:Reproducibility of Results; D018667:Tilt-Table Test
chemical_list: D000978:Antiparkinson Agents; D015259:Dopamine Agents; D007980:Levodopa; D009638:Norepinephrine; D004837:Epinephrine