Resveratrol inhibits electrical activity of paraventricular nucleus neurons in rat hypothalamic slices.
To study the role of resveratrol in the discharges of neurons in paraventricular nucleus (PVN) in hypothalamic slices, extracellular single-unit discharge recording technique was used. The effects of resveratrol were examined with glass microelectrodes in the rat PVN neurons at resting potential level. The results were as follows: (1) In response to the application of resveratrol (0.05, 0.5, 5.0 μmol/L, n=29) to the superfusate for 2 min, the spontaneous discharge rate (SDR) of neurons in 28/29 (96.6%) hypothalamic slices significantly decreased in a dose-dependent manner; (2) Pretreatment with L-glutamate (0.2 mmol/L) led to a marked increase in the SDR in all 8/8 (100%) slices in an epileptiform pattern. The increased discharges were suppressed by the application of resveratrol (5.0 mmol/L) in all 8 slices; (3) In 8 slices, perfusion of the selective L-type calcium channel agonist, Bay K8644 (0.1 μmol/L), induced a significant increase in the discharge rate in 8/8 (100%) slices. Resveratrol (5.0 μmol/L) significantly attenuated the increased SDR in all 8 slices; (4) Pretreatment with the nitric oxide synthase (NOS) inhibitor N(ω)-nitro-L-arginine methyl ester (L-NAME, 50 μmol/L) increased SDR in 7/8 (87.5%) slices, but did not affect the inhibitory effect of resveratrol (5.0 μmol/L). These results suggest that resveratrol inhibits the electrical activity of PVN neurons and exerts neuroprotective actions on central neurons. The inhibitory effect of resveratrol is possibly related to the blockade of L-type calcium channel, but not due to NO release.
Wang
Ru
R
Department of Physiology, Institute of Basic Medicine, Hebei Medical University, Shijiazhuang 050017, China.
Xiao
Lin
L
Ma
Hui-Juan
HJ
Zhang
Li-Hua
LH
He
Rui-Rong
RR
Wu
Yu-Ming
YM
D001498:3-Pyridinecarboxylic acid, 1,4-dihydro-2,6-dimethyl-5-nitro-4-(2-(trifluoromethyl)phenyl)-, Methyl ester / Q000494:pharmacology; D000200:Action Potentials; D000818:Animals; D002120:Calcium Channel Agonists / Q000494:pharmacology; D020746:Calcium Channels, L-Type / Q000378:metabolism; D018698:Glutamic Acid / Q000494:pharmacology; D066298:In Vitro Techniques; D008839:Microelectrodes; D019331:NG-Nitroarginine Methyl Ester / Q000494:pharmacology; D009474:Neurons / Q000187:drug effects*; D010286:Paraventricular Hypothalamic Nucleus / Q000166:cytology*; D051381:Rats; D017207:Rats, Sprague-Dawley; D000077185:Resveratrol; D013267:Stilbenes / Q000494:pharmacology*
D002120:Calcium Channel Agonists; 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; D019331:NG-Nitroarginine Methyl Ester