Mares P, Folbergrová J, Langmeier M, Haugvicová R, Kubová H
Institute of Physiology, Academy of Sciences of the Czech Republic, Prague.
Epilepsia. 1997 Jul;38(7):767-76. doi: 10.1111/j.1528-1157.1997.tb01463.x.
We wished to characterize the convulsant effect of homocysteic acid (HCA) in developing rats.
Seizures were induced in 7-, 12-, 18-, and 25-day-old rats by intraperitoneal (i.p.) administration of D,L-HCA and in 12-day-old rats by i.p. injection of L- and D-stereoisomers of HCA. The animals were observed for 30 min after injection. The incidence, latencies, pattern of motor seizures, and all behavioral phenomena were noted. Fifty percent convulsant dose (CD50) values were calculated by probit analysis. Electrocorticograms (ECoG) were recorded after injection.
HCA did not elicit minimal clonic seizures whereas generalized tonic-clonic seizures (GTCS) occurred in all the age groups studied. Flexion (emprosthotonic) convulsions occurred to postnatal day 18. ECoG recordings exhibited delta activity in younger pups and sharp graphoelements in older pups, but electroclinical correlation was poor. Young animals were more sensitive to the convulsant effect of D,L-HCA. In addition, D-HCA was significantly more effective than L-HCA in inducing both flexion and generalized seizures.
Our data clearly indicate that seizures induced by HCA differ from those evoked by homocysteine. There are no qualitative differences in the motor pattern of seizures induced by the two stereoisomers of HCA, but marked differences were apparent in the very first signs of their action. These differences might be due to interaction with different glutamate receptor subtypes.
我们希望描述同型半胱氨酸（HCA）对发育中大鼠的惊厥作用。
通过腹腔注射D，L - HCA诱导7日龄、12日龄、18日龄和25日龄大鼠惊厥发作，并通过腹腔注射HCA的L型和D型立体异构体诱导12日龄大鼠惊厥发作。注射后观察动物30分钟。记录发作发生率、潜伏期、运动性惊厥模式及所有行为现象。通过概率分析计算半数惊厥剂量（CD50）值。注射后记录脑电图（ECoG）。
HCA未引发最小阵挛性惊厥，而在所研究的所有年龄组中均出现全身性强直 - 阵挛性惊厥（GTCS）。屈曲（前弓反张）性惊厥持续到出生后第18天。ECoG记录显示幼鼠有δ活动，年长幼鼠有尖锐图形元素，但电临床相关性较差。幼龄动物对D，L - HCA的惊厥作用更敏感。此外，D - HCA在诱导屈曲性和全身性惊厥方面明显比L - HCA更有效。
我们的数据清楚地表明，HCA诱导的惊厥与同型半胱氨酸诱发的惊厥不同。HCA的两种立体异构体诱导的惊厥运动模式没有质的差异，但在其作用的最初迹象中明显存在显著差异。这些差异可能是由于与不同的谷氨酸受体亚型相互作用所致。
