Takazawa A, Abraham W C, Bilkey D K
Department of Psychology, University of Otago, Dunedin, New Zealand.
Epilepsy Res. 1990 Nov;7(2):86-94. doi: 10.1016/0920-1211(90)90093-b.
The time-dependent pro- and anticonvulsant effects of cysteamine, a depletor of somatostatin, were investigated on the development and expression of amygdaloid kindled seizures. Acute administration of cysteamine (25-400 mg/kg, i.p.) produced a dose-dependent potentiation of kindled seizures when evoked 4 h after the drug. However, the seizures initiated 1 day after drug administration were dose-dependently suppressed. Furthermore, elicitation of seizures 4 h after cysteamine enhanced its anticonvulsant effects at 1 day after the drug, causing a parallel left shift of the dose-response curve. Since it has been reported that somatostatin is released during generalized seizures, the seizures given 4 h after cysteamine may encourage the somatostatin depletion by cysteamine and thereby potentiate its later anticonvulsant effects. The repeated administration of cysteamine (100 mg/kg, i.p.) during kindling development strongly retarded the development of generalized seizures but not the development of focal seizures or of afterdischarges in the amygdala. In contrast to the acute experiments, kindling stimulation given 4 h after each cysteamine treatment did not augment the blocking effect on kindling development. These data indicate that chronic cysteamine treatment has a strong inhibitory effect on the development of amygdaloid kindling.
研究了生长抑素耗竭剂半胱胺对杏仁核点燃性癫痫发作的发生和表达的时间依赖性促惊厥和抗惊厥作用。急性给予半胱胺（25 - 400毫克/千克，腹腔注射）后4小时诱发点燃性癫痫发作时，会产生剂量依赖性的癫痫发作增强作用。然而，给药1天后引发的癫痫发作则呈剂量依赖性受到抑制。此外，半胱胺给药后4小时诱发癫痫发作会增强其在给药1天后的抗惊厥作用，导致剂量反应曲线平行左移。由于已有报道称全身性癫痫发作期间会释放生长抑素，半胱胺给药后4小时给予的癫痫发作可能会促使半胱胺导致生长抑素耗竭，从而增强其后期的抗惊厥作用。在点燃发展过程中反复给予半胱胺（100毫克/千克，腹腔注射）会强烈延缓全身性癫痫发作的发展，但不会延缓局灶性癫痫发作或杏仁核后放电的发展。与急性实验不同，每次半胱胺治疗后4小时给予点燃刺激并不会增强对点燃发展的阻断作用。这些数据表明，慢性半胱胺治疗对杏仁核点燃具有强烈的抑制作用。
