[Eph in the mechanism of mossy fiber axon sprouting in dentate gyrus in rats with chronic temporal lobe epilepsy].

Abstract

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).

CONCLUSION:

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.

• Authors: Wei-ping Liu, Bo Xiao, Shu-yu Li, Xiao-qin Lu
• Journal: Zhong nan da xue xue bao. Yi xue ban = Journal of Central South University. Medical sciences (Zhong Nan Da Xue Xue Bao Yi Xue Ban) Vol. 33 Issue 8 Pg. 657-62 (Aug 2008) ISSN: 1672-7347 [Print] China
• PMID: 18772502 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)

Chemical References

• Ephrin-A3
• RNA, Messenger
• EPHA5 protein, human
• Receptor, EphA5

Topics

• Animals
• Axons (physiology)
• Chromosome Pairing (physiology)
• Dentate Gyrus (physiopathology)
• Down-Regulation
• Ephrin-A3 (biosynthesis)
• Epilepsy, Temporal Lobe (chemically induced, metabolism, physiopathology)
• RNA, Messenger (biosynthesis, genetics)
• Rats
• Receptor, EphA5 (biosynthesis)
• Status Epilepticus (chemically induced, metabolism, physiopathology)