Responses of heat shock proteins hsp27, alpha B-crystallin, and hsp70 in rat brain after kainic acid-induced seizure activity

Citation
K. Kato et al., Responses of heat shock proteins hsp27, alpha B-crystallin, and hsp70 in rat brain after kainic acid-induced seizure activity, J NEUROCHEM, 73(1), 1999, pp. 229-236
Citations number
31
Language
INGLESE
art.tipo
Article
Categorie Soggetti
Neurosciences & Behavoir
Journal title
JOURNAL OF NEUROCHEMISTRY
ISSN journal
0022-3042 → ACNP
Volume
73
Issue
1
Year of publication
1999
Pages
229 - 236
Database
ISI
SICI code
0022-3042(199907)73:1<229:ROHSPH>2.0.ZU;2-1
Abstract
We determined the changes in the levels of the mammalian small heat shock p rotein of 25-28 kDa (hsp27) and the hsp alpha B-crystallin in various regio ns of rat brain after kainic acid-induced seizure activity by means of spec ific immunoassays. The levels of hsp27 in the hippocampus and entorhinal co rtex were markedly increased and reached a maximum (1.5-2 mu g/mg of protei n) 2-4 days after the seizure. The levels of hsp27 in these regions were co nsiderably high even 10 days after the seizure. A marked increase in levels of mRNA for hsp27 was also observed in the hippocampus of rats 1-2 days af ter the seizure. A severalfold increase in the levels of alpha B-crystallin was observed in the hippocampus and entorhinal cortex of rats 2 days after the seizure. However, the maximum levels were <50 ng/mg of protein. The le vels of protein sulfhydryl group and glutathione were significantly reduced in the hippocampus of rats at 24 h after the seizure, which might have enh anced the expressions of hsp27 and alpha B-crystallin. The expression of in ducible mammalian hsp of 70 kDa (hsp70) was also enhanced in the hippocampu s of rats after the seizure, as detected by western and northern blotting a nalyses. Immunohistochemically, an intensive staining of hsp27 was observed in both glial cells and neurons in the hippocampus, piriform cortex, and e ntorhinal cortex of rats with kainic acid-induced seizure. However, in the cerebellum, where the receptors for kainic acid are also rich, hsp27 was ba rely induced in the same rats. This might be due to high levels of the cere bellar calcium-binding proteins parvalbumin and 28-kDa calbindin-D, which m ight have a protective effect against the kainic acid-inducible damage.