Effects of luteolin on learning acquisition in rats: involvement of the central cholinergic system.
The study was conducted to investigate the ameliorating effects of luteolin on memory acquisition in rats. The effects of luteolin on scopolamine-induced impairment of passive avoidance response were evaluated primarily, as well as the role of the central nervous system through the use of central neurotoxins and central nervous antagonists. Luteolin was not reversed by scopolamine N-methylbromide (M-SCOP) but blocked the impairment of learning acquisition induced by cholinergic neurotoxin (ethylcholine aziridinium, AF64A) and muscarinic (scopolamine hydrobromide, SCOP) and nicotinic (mecamylamine, MECA) receptor antagonists. However, it did not block dopaminergic neurotoxin (6-hydroxydopamine, 6-OHDA)-induced and serotonergic neurotoxin (5,7-dihydroxytryptamine, 5,7-DHT)-induced impairments. From these results, we suggest that the attenuating effect of luteolin (10 mg/kg, i.p.) on the deficits of passive avoidance performance induced by SCOP may be related to the increases in the activities of central muscarinic and nicotinic receptors.
Tsai
Fan-Shiu
FS
Institute of Chinese Pharmaceutical Sciences, China Medical University, Taichung, Taiwan, ROC.
Peng
Wen-Huang
WH
Wang
Wen-Hsin
WH
Wu
Chi-Rei
CR
Hsieh
Chia-Chang
CC
Lin
Yao-Tung
YT
Feng
Ifrim-Chen
IC
Hsieh
Ming-Tsuen
MT
D000818:Animals; D001362:Avoidance Learning / Q000187:drug effects*; D047311:Luteolin / Q000494:pharmacology*; D008297:Male; D008568:Memory / Q000187:drug effects*; D009498:Neurotoxins / Q000633:toxicity; D051381:Rats; D017207:Rats, Sprague-Dawley; D011976:Receptors, Muscarinic / Q000378:metabolism; D011978:Receptors, Nicotinic / Q000378:metabolism
D009498:Neurotoxins; D011976:Receptors, Muscarinic; D011978:Receptors, Nicotinic; D047311:Luteolin