Hyperexcitability and changes in activities of Ca2+/calmodulin-dependent kinase II and mitogen-activated protein kinase in the hippocampus of rats exposed to 1-bromopropane

Fueta, Y; Fukunaga, K; Ishidao, T; Hori, H

HERO ID

1717488

Reference Type

Journal Article

Year

2002

Language

English

PMID

12467892

HERO ID 1717488
In Press No
Year 2002
Title Hyperexcitability and changes in activities of Ca2+/calmodulin-dependent kinase II and mitogen-activated protein kinase in the hippocampus of rats exposed to 1-bromopropane
Authors Fueta, Y; Fukunaga, K; Ishidao, T; Hori, H
Journal Life Sciences
Volume 72
Issue 4-5
Page Numbers 521-529
Abstract Chronic inhalation of 1-bromopropane (1-BP), a substitute of ozone-depleting chlorofluorocarbons, has been suspected of having central neurotoxicity (Clinical Neurology and Neurosurgery 101 (1999) 199; Journal of Occupational Health 44 (2002) 1) for humans. In animal experiments, 1-BP inhalation (1500 ppm) caused hyperexcitability in the CA1 and the dentate gyrus (DG) [Journal of Occupational Health 42 (2000) 149, Journal of Occupational Health 44 (2002) 156]. We studied whether the hyperexcitability is associated with changes of Ca2+/calmodulin-dependent kinase II (CaMKII), mitogen-activated protein kinase (MAPK), and protein kinase C (PKC). Male Wistar rats were exposed to 1-BP for 6 hours in a day in an exposure chamber with a concentration of 700 ppm for 8 weeks. After the inhalation, paired-pulse ratios of field excitatory postsynaptic potentials and population spikes (PSs) were analyzed in the CA1 and DG of hippocampal slices. Control rats were then given fresh air in the inhalation chamber. Semiquantitative immunoblotting analyses of protein kinases using antibodies against active and conventional protein kinases were done using the whole hippocampus. A paired-pulse ratio of PS was increased at the 5 ms interpulse interval in the CA1 and at the 10-20 ms interpulse intervals in the DG. The amount of active MAPK and total amount of CaMKIIalpha and beta were significantly increased by 28, 29, and 46% compared to control, respectively, without any change in PKC activity. In contrast, the amount of active CaMKIIbeta was decreased to 78%. These results suggest that modifications of intracellular signaling cascades are associated with hyperexcitability that occurred in the hippocampal formation of rats exposed to the chronic inhalation of 1-BP.
Doi 10.1016/S0024-3205(02)02247-6
Pmid 12467892
Wosid WOS:000180261300019
Url http://www.sciencedirect.com/science/article/pii/S0024320502022476
Is Certified Translation No
Dupe Override No
Comments Source: Web of Science WOS:000180261300019
Is Public Yes
Language Text English
Keyword hyperexcitability; CaMKIII; MAPK; inhalation; 1-bromopropane; rat hippocampus