The locus coeruleus and dopaminergic function in rat brain: implications to parkinsonism.
Clinical and experimental evidence suggests that degeneration of the locus coeruleus (LC) may be responsible for certain symptoms of Parkinson's disease (PD). We have, therefore, studied the effects of LC lesion on dopamine (DA) metabolism in the rat striatum. Unilateral depletion of norepinephrine (NE) was obtained by stereotaxic injection of 6-hydroxydopamine (6-OHDA) into the dorsal NE bundle (DNEB). Rats were sacrificed 1 or 3 weeks after lesioning. 6-OHDA induced approximately 50% depletion of NE in the ipsilateral hippocampus at 1 week postinjection, and over 75% depletion after 3 weeks. DNEB lesions had no effect on DA or DOPAC levels in the ipsi- or contralateral striatum at either time point. Lesions also failed to affect DA synthesis or utilization in either striatum. The metabolism of exogenous levodopa in the striatum was also unaffected. It is suggested that any possible effect of the LC on DA transmission in the striatum is not mediated by the DNEB.
Reches
A
A
Department of Neurology, Hadassah University Hospital, Jerusalem, Israel.
Meiner
Z
Z
D000818:Animals; D001679:Biogenic Amines / Q000378:metabolism; D003342:Corpus Striatum / Q000378:metabolism; D004298:Dopamine / Q000378:metabolism*; D007980:Levodopa / Q000378:metabolism; D008125:Locus Coeruleus / Q000378:metabolism*; D008297:Male; D009434:Neural Pathways / Q000378:metabolism; D010300:Parkinson Disease / Q000378:metabolism*; D051381:Rats; D011919:Rats, Inbred Strains; D013238:Stereotaxic Techniques; D013378:Substantia Nigra / Q000378:metabolism
D001679:Biogenic Amines; D007980:Levodopa; D004298:Dopamine