Hypersensitivity of cortical muscarinic receptors in Parkinson's disease demonstrated by PET

• Published in: Acta neurologica Scandinavica Vol. 91; no. 6; p. 437
• Main Authors: Asahina, M, Shinotoh, H, Hirayama, K, Suhara, T, Shishido, F, Inoue, O, Tateno, Y
• Format: Journal Article
• Language: English
• Published: Denmark 01.06.1995
• Subjects: Aged; Brain - diagnostic imaging; Brain - metabolism; Brain - physiopathology; Cognition Disorders - diagnosis; Cognition Disorders - etiology; Female; Humans; Male; Middle Aged; Neuropsychological Tests; Parkinson Disease - diagnostic imaging; Parkinson Disease - physiopathology; Positron-Emission Tomography; Receptors, Muscarinic - physiology; Time Factors
• ISSN: 0001-6314
• DOI: 10.1111/j.1600-0404.1995.tb00443.x

The status of muscarinic receptors (mAChRs) is not clear in Parkinson's disease (PD). We measured mAChR binding in the brain of eight patients with PD and eight, age-matched, healthy controls by positron emission tomography (PET) and [11C]N-methyl-4-piperidyl benzilate ([11C]NMPB). PD patients were not demented according to DSM III criteria but showed significant frontal lobe dysfunction in the Modified Wisconsin Card Sorting Test. A mean K3 value, which is an index of mAChR binding calculated by a graphical method, was 20% higher in the frontal cortex of PD patients than controls (p < 0.05). Hypersensitivity of mAChRs in the frontal cortex of PD patients may be a response to a loss of ascending cholinergic input to that region, and may relate to frontal lobe dysfunction in PD.