Effects of methylphenidate and pentobarbital on the spontaneous activity levels of rats with selective hippocampal system damage.
The effects of various types of experimentally-induced neural damage involving selective areas of the hippocampal system on spontaneous non-operant activity were studied in adult male rats using stabilimeter apparatus. A hierarchy of lesion-induced activity increases relative to sham-lesioned controls was revealed in which colchicine-induced dentate granule cell lesions produced the greatest increase in activity and kainic acid-induced pyramidal cell lesions produced the least. Methylphenidate (0.2, 0.4, 2.0, 4.0, 8.0 mg/kg) tended to increase this activity in a dose-dependent manner while pentobarbital (0.5, 1.0, 5.0, 10.0 mg/kg) tended to decrease it. These results indicate that such neural damage does not sufficiently alter the responsivity of rats to these drugs to produce a "paradoxical" effect although some lesion group differences in drug responsivity were seen. All this is discussed in light of the neuro-architecture of this system.
D000818:Animals; D003078:Colchicine / Q000494:pharmacology; D006624:Hippocampus / Q000187:drug effects / Q000502:physiology*; D007608:Kainic Acid / Q000494:pharmacology; D008297:Male; D008774:Methylphenidate / Q000494:pharmacology*; D009043:Motor Activity / Q000187:drug effects*; D010424:Pentobarbital / Q000494:pharmacology*; D051381:Rats; D011919:Rats, Inbred Strains
D008774:Methylphenidate; D010424:Pentobarbital; D007608:Kainic Acid; D003078:Colchicine