Structural and biochemical changes in rat cerebral cortex after neonatal 6-hydroxydopamine administration.
Newborn rats received an intracisternal injection of 6-hydroxydopamine (100 micrograms) within 16 h after birth. Treatment effects upon noradrenaline uptake (with or without desmethylimipramine pre-incubation), endogenous noradrenaline, dopamine, and serotonin were biochemically assayed. Noradrenaline uptake and endogenous noradrenaline content were permanently reduced to less than 5% of control values. Reduction of endogenous dopamine content was less marked: at day 60, values were about 40% of controls. Serotonin content remained unaffected. Cell density countings in postnatal day 15 temporal cortex revealed an about 16% reduction in layers II and III of treated animals. These modifications of cortical geometry were discussed with reference to measurements of cortical thickness and ultrastructural observations on postnatal days 2, 5 and 15. Both supranormal involution and growth processes might result from the neurotoxin treatment. Whereas some of the degeneration processes might be due o general cytotoxic effects, this is less likely for the supranormal growth processes.
D000818:Animals; D001923:Brain Chemistry; D002540:Cerebral Cortex / Q000032:analysis / Q000187:drug effects* / Q000648:ultrastructure; D004298:Dopamine / Q000032:analysis; D006892:Hydroxydopamines / Q000494:pharmacology*; D007276:Injections, Intraventricular; D008854:Microscopy, Electron; D009638:Norepinephrine / Q000032:analysis / Q000378:metabolism; D051381:Rats; D012701:Serotonin / Q000032:analysis
D006892:Hydroxydopamines; D012701:Serotonin; D004298:Dopamine; D009638:Norepinephrine