[Effect of xymedone on high-voltage-activated Ca2+ currents in pyramidal neurons of the entorhinal cortex].
The effect of xymedon on Ca2+ currents in entorhinal cortex LIII pyramidal neurons was studied using brain slices from 10-17-day old rats, which were analyzed by means of the infrared video assisted whole cell patch clamp recording. The sample slices were superfused with artificial cerebrospinal fluid containing tetrodotoxin, 4-aminopyridine, and tetraethylammonium for the blocking of Na+ and K+ channels, respectively. Xymedone was added to artificial cerebrospinal fluid and to all extracellular solutions. The slices were exposed to different concentrations of xymedone for 3 hours followed by patch-clamp recordings. Control recordings were run with the vehicle. Xymedone in a concentration of 0.01 mM decreased the maximum voltage-dependent Ca2+ current amplitude by 39.8 %, while 1 mM of xymedone inhibited the Ca2+ currents almost completely. The obtained data showed for the first time that xymedone exhibits a calcium channel blocker activity in neurons. Possible neuroprotective mechanisms of xymedone are discussed.
I S
IS
Raginov
G V
GV
Cherepnev
R S
RS
Garaev
D000818:Animals; D002121:Calcium Channel Blockers / Q000494:pharmacology*; D015220:Calcium Channels / Q000378:metabolism*; D004305:Dose-Response Relationship, Drug; D018728:Entorhinal Cortex / Q000166:cytology / Q000187:drug effects* / Q000378:metabolism; D066298:In Vitro Techniques; D017966:Pyramidal Cells / Q000187:drug effects* / Q000378:metabolism; D011743:Pyrimidines / Q000494:pharmacology*; D051381:Rats
D002121:Calcium Channel Blockers; D015220:Calcium Channels; D011743:Pyrimidines; C069705:xymedon