Melatonin protects 6-OHDA-induced neuronal death of nigrostriatal dopaminergic system.
In vivo neuroprotective effects of melatonin on the nigrostriatal dopaminergic system in rats unilateral 6-hydroxydopamine (6-OHDA) lesions were tested. Two weeks after lesioning the dopamine receptor agonist, apomorphine produced rotational asymmetry. In contrast, melatonin treatment significantly reduced the motor deficit following apomorphine challenge. Analysis by tyrosine hydroxylase (TH) immunocytochemistry revealed the loss of cell bodies in the substantia nigra (SN) and absence of terminals in the dorsolateral striatum ipsilaterally. Melatonin treatment also resulted in the survival of dopaminergic neurons in SN and TH-immuoreactive terminals in the dorsolateral striatum. These behavioral and histochemical results may indicate a neuroprotective action of melatonin and suggest a potential pharmacological role in the treatment of Parkinson's disease.
Department of Pharmacology, College of Medicine and Neuroscience Research Institute Medical Research Center, Seoul National University, Korea.
Y S
YS
Kim
W S
WS
Joo
B K
BK
Jin
Y H
YH
Cho
H H
HH
Baik
C W
CW
Park
D000818:Animals; D000975:Antioxidants / Q000494:pharmacology; D016923:Cell Death / Q000187:drug effects; D003342:Corpus Striatum / Q000166:cytology* / Q000187:drug effects; D004298:Dopamine / Q000502:physiology*; D007150:Immunohistochemistry; D008297:Male; D008550:Melatonin / Q000494:pharmacology*; D008845:Microinjections; D009474:Neurons / Q000187:drug effects* / Q000201:enzymology; D018696:Neuroprotective Agents / Q000494:pharmacology*; D016627:Oxidopamine / Q000008:administration & dosage / Q000037:antagonists & inhibitors* / Q000633:toxicity; D051381:Rats; D017207:Rats, Sprague-Dawley; D013378:Substantia Nigra / Q000166:cytology* / Q000187:drug effects; D013565:Sympatholytics / Q000008:administration & dosage / Q000633:toxicity*; D014446:Tyrosine 3-Monooxygenase / Q000378:metabolism
D000975:Antioxidants; D018696:Neuroprotective Agents; D013565:Sympatholytics; D016627:Oxidopamine; D014446:Tyrosine 3-Monooxygenase; D008550:Melatonin; D004298:Dopamine