Second messengers in Parkinson’s disease
The second messenger systems coupled to phosphoinositide turnover, diacylglycerol (DG)-protein kinase C (PKC) and inositol 1,4,5-trisphosphate (IP3)-Ca2+ systems, were studied in the striatum of postmortem brains from 20 patients with Parkinson’s disease (PD) (Yahr III, IV and V), using 3H-4β phorbol 12,13-dibutyrate (3H-PDBu) and 3H-IP3 as the respective ligands. In the PD striatum, the specific bindings for 3H-PDBu and 3H-IP3 were not altered when all the patients without dementia, Yahr (III + IV) patients or Yahr V patients, without dementia were compared with control subjects. However, they were significantly decreased in the Yahr V patients with dementia (PDD) by 38% and 78%, respectively. These results suggest that the second messenger sites coupled to the phosphoinositide system are not concentrated in the nigrostriatal dopaminergic neurons and that striatal pathophysiology of PDD is different from that of PD without dementia.
KeywordsAdenylate Cyclase Neurochemical Pathology Quinuclidinyl Benzilate Phorbol Ester Receptor Phosphoinositide System
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- Birkmayer W, Riederer P (1985) Die Parkinson-Krankheit. Biochemie, Klinik, Therapie, 2. Aufl. Springer, Wien New YorkGoogle Scholar
- Yoshihara C, Saito N, Taniyama K, Tanaka C (1991) Differential localization of four subspecies of protein kinase C in the rat striatum and substantia nigra. J Neurosci (in press)Google Scholar