C-fos mRNA In Rat Brain Research Articles

택지개발 현장 내 비위생매립지의 매립쓰레기 처리방안 연구

China is one of countries with the highest mercury production in the world. The Guizhou Province in Southwestern China is currently one of the world's most important mercury production areas. In order to study the neurotoxicity of rice from Qingzhen Chemical Plant area and probe into the signal transduction molecular mechanism of injury in rat brain stimulation by mercury contaminated rice. The rats were exposed to mercury contaminated rice for 20 d. Both of the measurements of NO and NOS were processed according to the protocol of the kit. The effect of Hg contaminated rice on the expression of c-fos mRNA in rat brain and the expression of c-FOS protein in cortex, hippocampus were observed using reverse transcription polymerase chain reaction (RT-PCR) and immunocytochemical methods. The results showed the neural transmitter NO and NOS in brain were significantly change between exposure groups and control group; the mercury polluted rice induced significantly the expression of c-fos mRNA; the c-FOS positive cells in hippocampus and cortex of exposure groups were significant different from control group (p < 0.01). It could be concluded that nitric oxide was involved in mercury contaminated rice induced immediate early gene c-fos expressions in the rat brain. Through food chain, local ecosystem and health of local people iave been deteriorated seriously by mercury. This serious situation will last a long period. In order to alleviate mercury pollution, more work needs to do.

Chronological Expression and its Significance of c-jun and c-fos mRNA in Rat Brain.

We investigated the expression of c-jun and c-fos proto-oncogenes and their distribution in the brain of newborn to adult rats to determine the relationship between protooncogene expression and brain development, by the reverse transcription-polymerase chain rection (RT-PCR) method, in situ hybridization and immunohistochemistry. In the RT-PCR analysis, the cDNA fragments of c-jun and c-fos were amplified with expected-sizes, and the expression levels were fixed through all ages examined. The in situ hybridization showed that the expression of c-jun and c-fos mRNA was located at the cytoplasm of most neurons and some glial cells of the entire portions of the cerebrum, brainstem and cerebellum until 300 days after birth. c-jun protein immunoreactivity was detected in the nucleus of neurons which demonstrated a positive signal by in situ hybridization. Our results suggest that even after neuroblasts differentiate to mature neurons, c-jun and c-fos genes may have a role in the preservation of the neuronal function of the rat central nervous system.

Involvement of gamma-aminobutyric acid and N-methyl-D-aspartate receptors in the inhibitory effect of ethanol on pentylenetetrazole-induced c-fos expression in rat brain.

The expression of c-fos mRNA in rat brain was induced by intraperitoneal administration of pentylenetetrazole (PTZ) and picrotoxin, which act on the picrotoxin binding site of the gamma-aminobutyric acid-benzodiazepine (GABA-BZ) receptor complex, by N-methyl-D-aspartate (NMDA) and kainic acid, agonists of different classes of glutamate receptors and by caffeine, an antagonist of adenosine receptors. The actions of PTZ and picrotoxin but not that of NMDA were blocked by ethanol and the NMDA-receptor antagonist, MK-801. Ro 15-4513 partially reversed the inhibitory effect of ethanol on PTZ-induced c-fos mRNA synthesis. Acute ethanol administration blocked the actions of PTZ and NMDA without affecting the response to kainic acid or caffeine. Taken together, these data suggest that ethanol blocks c-fos gene activation by noncompetitive antagonists of the GABA-BZ receptor via actions on both the NMDA and GABA receptors.

Expression of c-fos mRNA in rat brain after intracerebroventricular administration of corticotropin-releasing hormone

Expression of the proto-oncogene c-fos is known to increase in rat brain following various types of seizures. Measuring c-fos mRNA or protein levels was shown to be a good cellular marker for neurons activated during central nervous system (CNS) excitation. In this study, we used in situ hybridization analysis of c-fos mRNA to determine brain regions activated by a peptide that has been closely linked to stress responsivity and kindling-like seizure activity. Corticotropin-releasing hormone (CRH) was injected into the left lateral ventricle of rats and produced the late onset of seizures between 1.5-5 h after its administration. Rats were sacrificed at various time points after the administration of CRH or sterile water, and c-fos mRNA levels were determined. In the preseizure state, CRH increased c-fos unilaterally in several cerebral cortical structures (most prominently in the dorsal endopiriform nucleus and in the piriform and insular cortices). CRH-induced seizures increased c-fos bilaterally in the same cortical regions, and in addition, in the hippocampus and olfactory bulb. The data are congruous with the hypothesis that intracerebroventricularly (i.c.v.) administered CRH elicits a rapid kindling-like response.