The effects of local anesthetics on intracellular Ca2+ release from ryanodine-sensitive Ca2+ stores in gerbil hippocampal neurons.
OBJECTIVE
To examine the effects of procaine and lidocaine on intracellular Ca(2+) release from sarcoplasmic reticulum ryanodine-sensitive Ca(2+) stores.


METHODS
The experiment was performed on hippocampal slices from 60-80 g male Mongolian gerbils. Levels of intracellular Ca(2+) concentration in the slices were measured by microfluorometry. The slices were perfused with 50 mmol/L KCl containing medium for 30 seconds. Then, the medium was switched to physiological medium. After 5 min of incubation, the slice was perfused with 20 mmol/L caffeine containing physiology medium for 2 min. Following incubation, the slice was superfused with physiological medium until the end of the experiment. The effects of procaine and lidocanin (100 micro mol/L) on caffeine-evoked Ca(2+) release were evaluated by adding them to the medium after high K(+) medium perfusion.


RESULTS
Caffeine induced a marked increase in intracellular Ca(2+) concentration which was then decreased 12% upon the addition of procaine (P < 0.05); however, lidocaine, did not induce a similar inhibitory reaction.


CONCLUSIONS
Procaine inhibits ryanodine-receptor mediated Ca(2+) release from intracellular Ca(2+) stores, while lidocaine may inhibit Ca(2+) release through other mechanisms.
Chen
Junfeng
J
Department of Anesthesiology, Shanghai Changning Center Hospital, Shanghai 200336, China. chenjf@81890.net
Xu
Weiren
W
Jiang
Hao
H
D000779:Anesthetics, Local / Q000494:pharmacology*; D000818:Animals; D002118:Calcium / Q000378:metabolism*; D005849:Gerbillinae; D006624:Hippocampus / Q000187:drug effects* / Q000378:metabolism; D008012:Lidocaine / Q000494:pharmacology; D008297:Male; D011343:Procaine / Q000494:pharmacology; D012433:Ryanodine / Q000494:pharmacology*; D019837:Ryanodine Receptor Calcium Release Channel / Q000502:physiology
D000779:Anesthetics, Local; D019837:Ryanodine Receptor Calcium Release Channel; D012433:Ryanodine; D011343:Procaine; D008012:Lidocaine; D002118:Calcium