Michelson H B, Lothman E W
Department of Neurology, University of Virginia Health Sciences Center, Charlottesville 22908.
Brain Res Dev Brain Res. 1991 Jul 16;61(1):79-85. doi: 10.1016/0165-3806(91)90116-z.
The present study investigated the acquisition and retention of kindling in immature rats. Postnatal (PN) 7-28-day-old rats were electrically kindled in the ventral hippocampus. Ten-second, 20-Hz stimulus trains were delivered every 5 min for 6 h on one day (short interval rapidly recurring hippocampal seizures, RRHS) or every 30 min for 9 h on each of two consecutive days (long interval RRHS). Afterdischarge durations (ADD) and behavioral seizure scores (BSS) were recorded following each stimulation. Animals of all ages kindled with both short and long interval RRHS, as manifested by lengthening of ADD and increasing BSS. With short interval RRHS, the course of kindling was erratic; with long interval RRHS, kindling proceeded smoothly over both test days. In PN 14-28 rats, the degree of kindling obtained on the first day of long interval RRHS was retained at the start of the second experimental day. In contrast, PN 7 rats showed a transient decrease in ADD and BSS from day 1 to day 2. Afterdischarge thresholds declined with maturation. Among the PN 14-28 animals, younger rats exhibited longer seizures at the outset of kindling and proceeded through kindling faster. Once established, kindled motor seizures also occurred with 2-s, 50-Hz stimulus trains. We conclude that rapid kindling occurs at all ages; however, PN 7 rats are less capable of retaining the kindling effect than are older rats.
本研究调查了幼龄大鼠点燃效应的获得与维持情况。对出生后（PN）7至28日龄的大鼠进行腹侧海马区的电点燃。在一天内每隔5分钟给予10秒、20赫兹的刺激串，持续6小时（短间隔快速反复海马癫痫发作，RRHS），或在连续两天中每天每隔30分钟给予9小时（长间隔RRHS）。每次刺激后记录发作后持续时间（ADD）和行为癫痫评分（BSS）。所有年龄段的动物通过ADD延长和BSS增加表现出短间隔和长间隔RRHS点燃效应。短间隔RRHS时，点燃过程不稳定；长间隔RRHS时，在两个测试日点燃过程进展顺利。在PN 14至28日龄大鼠中，长间隔RRHS第一天获得的点燃程度在第二个实验日开始时得以维持。相比之下，PN 7日龄大鼠从第1天到第2天ADD和BSS出现短暂下降。发作后阈值随成熟而下降。在PN 14至28日龄的动物中，较年幼的大鼠在点燃开始时发作时间更长，且点燃进展更快。一旦确立，2秒、50赫兹的刺激串也会引发点燃后的运动性癫痫发作。我们得出结论，所有年龄段都能快速点燃；然而，PN 7日龄大鼠比年长大鼠更难以维持点燃效应。
