[Eph in the mechanism of mossy fiber axon sprouting in dentate gyrus in rats with chronic temporal lobe epilepsy].
OBJECTIVE
To investigate the relationship among mossy fiber axon sprouting(MFS), synaptic reorganization, and the alteration of expression of Eph A5 and ephrin A3 in the dentate gyrus in rats with pilocarpine-induced chronic temporal lobe epilepsy.


METHODS
Mossy fiber sprouting and synaptic formation in rats were observed by Neo-Timm staining, after the acute status epilepticus and chronic spontaneous temporal lobe epilepsy induced by lithium-chloride and pilocarpine. In situ hybridization was used to detect ephrin A3 mRNA and an immunohistochemical staining was applied to determine Eph A5 protein.


RESULTS
In entorhinal cortex, only Eph A5 mRNA and protein expressed, which significantly decreased on Day 7 after pilocarpine induced status epilepticus(P<0.01),and resumed to normal levels on Day 30 (P>0.05). In the dentate granule cells, ephrin A3 mRNA reduced obviously on Day 7 after pilocarpine-induced status epilepticus (P<0.01), and returned to normal levels on Day 30 (P>0.05).


CONCLUSIONS
The down-regulation of Eph A5 mRNA and protein in entorhinal cortex and dentate gyrus, and ephrin A3 mRNA in dentate gyrus after status epilepticus may be part of the endogenous molecular mechanism of mossy fiber sprouting to the inner molecular layer of dentate gyrus.
Liu
Wei-ping
WP
Department of Neurology, Xiangya Hospital, Central South University, Changsha 410008, China. Aliu1220@163.com
Xiao
Bo
B
Li
Shu-yu
SY
Lu
Xiao-qin
XQ
D000818:Animals; D001369:Axons / Q000502:physiology*; D023902:Chromosome Pairing / Q000502:physiology; D018891:Dentate Gyrus / Q000503:physiopathology*; D015536:Down-Regulation; D036384:Ephrin-A3 / Q000096:biosynthesis*; D004833:Epilepsy, Temporal Lobe / Q000139:chemically induced / Q000378:metabolism* / Q000503:physiopathology; D012333:RNA, Messenger / Q000096:biosynthesis / Q000235:genetics; D051381:Rats; D036123:Receptor, EphA5 / Q000096:biosynthesis*; D013226:Status Epilepticus / Q000139:chemically induced / Q000378:metabolism / Q000503:physiopathology
D036384:Ephrin-A3; D012333:RNA, Messenger; C484173:EPHA5 protein, human; D036123:Receptor, EphA5