Impaired long-term potentiation-like plasticity of the trigeminal blink reflex circuit in Parkinson's disease.
We investigated the hypothesis that Parkinsons's disease (PD) is associated with abnormal plasticity of the neuronal circuits mediating blink reflex. We induced long-term potentiation (LTP)-like plasticity in trigeminal wide dynamic range neurons of the blink reflex circuit by pairing an high-frequency train of electrical stimuli over the right supraorbital nerve (SO) coincident with the R2 response elicited by a preceding SO stimulus. The facilitation of the R2 response after the induction protocol was markedly decreased in patients relative to controls. Treatment with dopaminergic drugs normalized the LTP-like plasticity of the R2 response. We conclude that nigrostriatal denervation disrupts LTP-like plasticity in the trigeminal reflex circuit.
Battaglia
Fortunato
F
Department of Physiology and Pharmacology, CUNY School of Medicine, New York, New York 10031, USA. fb@med.cuny.edu
Ghilardi
Maria Felice
MF
Quartarone
Angelo
A
Bagnato
Sergio
S
Girlanda
Paolo
P
Hallett
Mark
M
D000368:Aged; D000704:Analysis of Variance; D001767:Blinking / Q000502:physiology*; D004307:Dose-Response Relationship, Radiation; D004558:Electric Stimulation / Q000379:methods; D005260:Female; D007839:Functional Laterality; D006801:Humans; D017774:Long-Term Potentiation / Q000502:physiology*; D008297:Male; D008875:Middle Aged; D010300:Parkinson Disease / Q000473:pathology / Q000503:physiopathology*; D011930:Reaction Time / Q000502:physiology / Q000528:radiation effects; D014276:Trigeminal Nerve / Q000503:physiopathology* / Q000528:radiation effects