title: Resveratrol inhibits neuronal discharges in rat hippocampal CA1 area.
abstract: The effects of resveratrol on the discharges of neurons in CA1 area of rat hippocampal slices were examined by using extracellular recording technique. The results are as follows: (1) In response to the application of resveratrol (0.05, 0.5, 5.0 micromol/L, n=52) into the superfusate for 2 min, the spontaneous discharge rate of 46/52 (88.5%) neurons was significantly decreased in a dose-dependent manner; (2) Application of L-glutamate (0.2 mmol/L) into the superfusate led to a marked increase in discharge rate of all 8 (100%) slices in an epileptiform pattern. The increased discharges were suppressed by application of resveratrol (5.0 micromol/L); (3) In 7 slices, perfusion of the selective L-type calcium channel agonist, Bay K8644 (0.1 micromol/L), induced a significant increase in the discharge rate of 6/7 (85.7%) slices. The increased discharges were suppressed by application of resveratrol (5.0 micromol/L); (4) In 9 slices, perfusion of nitric oxide synthase (NOS) inhibitor N(G)-nitro-L-arginine methyl ester (L-NAME, 50 micromol/L) into the superfusate significantly augmented the discharge rate of 7/9 (77.8%) slices. Resveratrol (5.0 micromol/L) applied into the superfusate reduced the increased discharges of all 7/7 (100%) neurons; (5) In 10 units, the large-conductance Ca(2+)-activated K(+) channel blocker (tetraethylammonium chloride, TEA, 1 mmol/L) significantly increased the discharge rate of 9/10 (90%) slices. Resveratrol (5.0 micromol/L) applied into the superfusate inhibited the discharges of 8/9 (88.9%) slices. These results suggest that resveratrol inhibits the electrical activity of CA1 neurons. This effect may be related to the blockade of L-type calcium channel and a subsequent reduction of calcium influx, and probably has no association with large-conductance Ca(2+)-activated K(+) channel.
authors.affiliation: Department of Physiology, Institute of Basic Medicine, Hebei Medical University, Shijiazhuang 050017, China.
authors.forename: Ming
authors.initials: M
authors.lastname: Li
authors.forename: Qing-Shan
authors.initials: QS
authors.lastname: Wang
authors.forename: Yi
authors.initials: Y
authors.lastname: Chen
authors.forename: Ze-Min
authors.initials: ZM
authors.lastname: Wang
authors.forename: Zheng
authors.initials: Z
authors.lastname: Liu
authors.forename: Shu-Mei
authors.initials: SM
authors.lastname: Guo
mesh_terms: D001498:3-Pyridinecarboxylic acid, 1,4-dihydro-2,6-dimethyl-5-nitro-4-(2-(trifluoromethyl)phenyl)-, Methyl ester / Q000494:pharmacology; D000818:Animals; D002120:Calcium Channel Agonists / Q000494:pharmacology; D002121:Calcium Channel Blockers / Q000494:pharmacology*; D020746:Calcium Channels, L-Type; D004594:Electrophysiology; D018698:Glutamic Acid / Q000494:pharmacology; D006624:Hippocampus / Q000166:cytology / Q000502:physiology*; D008297:Male; D009474:Neurons / Q000502:physiology*; D051381:Rats; D017207:Rats, Sprague-Dawley; D000077185:Resveratrol; D013267:Stilbenes / Q000494:pharmacology*
chemical_list: D002120:Calcium Channel Agonists; D002121:Calcium Channel Blockers; D020746:Calcium Channels, L-Type; D013267:Stilbenes; D018698:Glutamic Acid; D001498:3-Pyridinecarboxylic acid, 1,4-dihydro-2,6-dimethyl-5-nitro-4-(2-(trifluoromethyl)phenyl)-, Methyl ester; D000077185:Resveratrol