Changes in the motor response to acute L-dopa challenge after unilateral microelectrode-guided posteroventral pallidotomy.
To determine the effect of unilateral posteroventral pallidotomy (PVP) on latency and duration of response to L-dopa ipsilateral and contralateral to the side of the lesion, six severe fluctuating Hoehn-Yahr IV patients with Parkinson's disease were evaluated 2 days before and after unilateral PVP. After an overnight drug holiday in a fasting state, patients were challenged with a single dose of 200/50 mg of L-dopa/ carbidopa. Sequential tapping tests every 5 minutes in both hands were used to measure changes in motor status. Duration of L-dopa effect was significantly longer after PVP (p < 0.03). Mean latency of the effect improved by 50% without reaching statistical significance. Despite a clear, asymmetric improvement of cardinal Parkinson's disease symptoms after unilateral PVP, changes in the dose-response L-dopa profile occurred symmetrically, suggesting that mechanisms underlying the two effects are distinct.
Merello
M
M
Movement Disorders Section, Raul Carrea Institute for Neurological Research (FLENI), Buenos Aires, Argentina.
Nouzeilles
M I
MI
Cammarotta
A
A
Pikielny
R
R
Leiguarda
R
R
D000328:Adult; D000704:Analysis of Variance; D000978:Antiparkinson Agents / Q000494:pharmacology / Q000627:therapeutic use*; D003131:Combined Modality Therapy; D004305:Dose-Response Relationship, Drug; D005260:Female; D005917:Globus Pallidus / Q000601:surgery*; D006801:Humans; D007980:Levodopa / Q000494:pharmacology* / Q000627:therapeutic use; D008297:Male; D008839:Microelectrodes; D008875:Middle Aged; D009043:Motor Activity / Q000187:drug effects*; D009460:Neurologic Examination; D010300:Parkinson Disease / Q000188:drug therapy* / Q000601:surgery*; D011446:Prospective Studies
D000978:Antiparkinson Agents; D007980:Levodopa