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Objective: To investigate whether mechanical stretch stimulation affects the expression of the immediate early gene c-fos mRNA in rat Achilles-derived tendon stem cells (TSCs) in vitro ., Methods: TSCs were isolated from the Achilles tendons of 8 weeks old male Sprague Dawley rats by enzymatic digestion method and cultured for 3 passages. The TSCs were stimulated by a uniaxial cyclic stretching loading system under the condition of 1 Hz, respectively with 4% or 8% stretch intensity for 0, 5, 15, 30, 60, and 120 minutes. At each time point, TSCs were collected to detect c-fos mRNA expressions and to find the best time-point T max by real-time fluorescence quantitative PCR. Then, TSCs were simulated with 2%, 4%, 6%, 8%, or 12% stretch intensity for T max to observe the relative expressions of c-fos mRNA under different stretch intensities. Next, TSCs were stretched for 0, 5, or 15 minutes respectively and followed by incubation at relax status up to T max to observe the changes of c-fos mRNA expressions after short period stimulation. Finally, TSCs were stimulated with 4% or 8% stretch intensity respectively for 0, T max , or 120 minutes to detect the expressions of the tenogenic differentiation related genes [collagen type I, tenomodulin (TNMD)], the osteogenic differentiation related genes [runt related transcription factor 2 (Runx2), distal-less homeobox 5 (Dlx5)], and the adipogenic differentiation related gene [fatty acid binding protein 4 (FABP4)]., Results: Under 4% or 8% stretch intensity, the relative expressions of c-fos mRNA significantly increased at 15 minutes ( P <0.05), reached the maximum at 30 minutes ( P <0.05), and returned to baseline at 60 minutes ( P >0.05) when compared with expression at 0 minute. Therefore, T max was 30 minutes. The stretch intensity of 2% was enough to cause the expression of c-fos mRNA at 30 minutes, and the expression was significantly higher under the stretch intensity of 6%, 8%, and 12% than 2% and 4% ( P <0.05). Even for a short period stimulation of 5 minutes, c-fos mRNA expression could still significantly increase at 30 minutes ( P <0.05). The relative expressions of differentiation related genes at 30 and 120 minutes showed no significant difference when compared with the expression at 0 minute under 4% stretch intensity ( P >0.05); but the relative expression of Runx2 gene significantly increased at 30 minutes, and the relative expressions of collagen type I, TNMD, Dlx5, and Runx2 increased at 120 minutes under 8% stretch intensity ( P <0.05)., Conclusion: Mechanical stretch stimulation can affect the relative expression of the immediate early gene c-fos mRNA of rat Achilles-derived tendon stem cells in vitro , and there is time- and intensity-dependence. It is suggested that the mechanical stimulation with different time or intensity may affect the differentiation of TSCs at early stage. This study is meaningful for the further study on TSCs intracellular mechanical signal transfer mechanism.

As an immediate early gene, c-fos plays a critical role in stimulating the synthesis and release of pituitary FSH via GnRH. To better understanding the mechanism how c-fos works in the transcription of FSHbeta under different frequency of pulsatile GnRH stimulation, this paper reviewed the signal trans- ductions initiated by c-fos in pituitary, which include cAMP pathway, MAPK pathway, Ca2+ /calmodulin-dependent kinases pathway and nuclear factor of activated T-cells (NFAT) pathway. It will be helpful for research in molecular targeted immunotherapy and eventually effective treatment to the infertility which resulted from defection or mutation of c-fos and c-fos related signal pathway elements.

Objective: To investigate the relationship between c-fos gene and filamentous actin (F-actin) in MG-63 osteoblasts under cyclic tensile stress., Methods: MG-63 osteoblasts were subjected to cyclic tensile stress (0.5 Hz, 2 000 microstrain) for 3, 6, and 12 h. The changes of c-fos gene were investigated by fluorescent quantitation polymerase chain reaction. Then the best loading time group was screened as the experimental group compared with 0 h group. The changes of F-actin and c-fos were investigated with or without cytochalasin D treatment., Results: Cyclic tensile stress induced high expression of c-fos mRNA, and peaked at 3 h. After loading, F-actin had a structure reorganization, but had no change in expression. After cytochalasin D treatment, the formation of stress fibers and the fluorescence intensity of F-actin cytoskeleton significantly reduced, meanwhile the c-fos mRNA expression was inhibited., Conclusion: After loading, there is only structure reorganization for F-actin, and the expression has not any change. That means the remodeling F-actin is the existing one. F-actin reorganization is an important part in c-fos gene expression induced by stress.

Objective: To investigate the effects of pyrroloquinoline quinine (PQQ) on proliferation and expression of c-fos, c-jun, CREB and PCNA in cultured Schwann cells., Methods: Schwann cells were cultured and purified in vitro. The purity of Schwann cells was identified by immunofluorescence of S-100. After synchronization of cell cycle by serum-free medium, different concentration of PQQ (0,1, 10, 100, 1,000, 10,000 nmol/L) were added into culture medium for 72 h. Flow cytometry was used to determine cell cycle. The content of c-fos, c-jun, and CREB mRNA were detected by RT-PCR, and the expression of PCNA protein was detected by Western blot., Results: After PQQ treatment, the percentage of cells in G0/G1 phase decreased and the percentage of cells in S and G2/M phase increased. After treated by PQQ at concentration of 1-10,000nmol/L, content of c-fos,c-jun,CREB mRNA was increased by 0.33,0.42 and 0. 52 fold (P < 0. 05). However, at concentration of 1 000 nmol/L, there was no difference in mRNAs content when compare to control (P >0.05). And it showed a decline at concentration of 10,000 nmol/L (P < 0.05). PCNA protein expression was up-regulated at PQQ concentration of 1-100 nmol/L. At 100 nmol/L, the expression increased by 1.17 fold (P < 0.05); However, at 1,000 nmol/L, there was no difference in PCNA expression when compared to control. And 10,000 nmol/L of PQQ inhibited the expression of PCNA (P < 0.05)., Conclusions: When treated with PQQ at concentration of 10-100 nmol/L, the proliferation of Schwann cells increased and the expression of c-fos,c-jun, CREB and PCNA was up-regulated.

Objective: To investigate the effects of transforming growth factor beta (TGF ) on c-fos gene expression in hepatic stellate cells., Methods: Hepatic stellate cells (HSC-T6) were cultured in the medium containing different concentrations of TGF (0.2, 1, and 5 ng/ml), and cells were collected at different time points of incubation (8, 24, 48, and 72 h). The total RNA of the HSCs was isolated and c-fos gene expression level were measured by reverse transcription polymerase chain reaction., Results: c-fos gene expression levels of HSCs cultured in the presence of low (0.2 ng/ml), moderate (1 ng/ml) and high (5 ng/ml) concentrations of TGF for 8, 24, 48 and 72 h were significantly greater than those of control group. The c-fos gene expression levels of HSCs increased gradually with the increment of TGF concentration, and significant differences in c-fos gene expression were found between the 3TGF groups., Conclusion: TGF strongly up-regulates c-fos gene expression in hepatic stellate cells.

Aim: To study the protective effect of ligustrazine against photoreceptor cell injury induced by N-methyl-N-nitrosourea (MNU) in Sprague-Dawley (SD) rats., Methods: Ligustrazine injections of different doses were injected intraperitoneally into 47-day female SD rats once a day and a single intraperitoneal injection of MNU 60 mg x kg(-1) was given to 50-day rats. At different intervals after MNU treatment,the animals were sacrificed. The apoptotic index of photoreceptor cells was calculated by TUNEL labeling at 24 h following MNU treatment; peripheral retinal damage was evaluated based on retinal thickness at the d 7 after MNU treatment, and the expression of c-jun and c-fos genes was detected by RT-PCR technique., Results: Ligustrazine injection could remarkably increase total thickness of peripheral retina and decrease apoptotic index of photoreceptor cells induced by MNU in a dose-dependent manner. Compared with MNU-treated rats, the gene expression of c-jun and c-fos was time-dependently down-regulated in ligustrazine-treated group., Conclusion: Ligustrazine injection partially protects against MNU-induced retinal damage by down-modulating the expression of c-jun and c-fos genes to inhibit apoptosis of photoreceptor cells.

Objective: To explore the mechanism of electroacupuncture at "Neiguan" (PC 6) improving acute myocardial ischemia., Methods: The rats were randomly divided into a sham operation group, a myocardial ischemia model group and a myocardial ischemia model plus electroacupuncture group. The acute myocardial ischemia model was developed byligation of the descending anterior branch of the coronary artery, and electroacupuncture was given at bilateral "Neiguan" (PC 6). Serum myocardial enzymes was determined by biochemical method and the expression of c-fos mRNA in myocardium was detected by using reverse transcription polymerase chain reaction (RT-PCR)., Results: The activities of serum myocardial enzymes and the expression of c-fos mRNA in ischemic myocardium were significantly increased as compared with those in the sham operation group (P < 0.05), and after electroacupuncture they were significantly decreased (P < 0.05)., Conclusion: The mechanism of electroacupuncture at "Neiguan" (PC 6) improving acute myochadial ischemia is possibly related with down-regulation of expression of c-fos mRNA in myocardium.

Objective: To explore the dynamic changes in the expression of c-fos, proliferation cell nuclear antigen (PCNA) and Bax in the intestinal tissue of scalded rats before and after resuscitation., Methods: Wistar rats inflicted with 30% TBSA full thickness scald were employed as the model and randomly divided into four groups with 8 in each group, i.e. 2.0, 2.5, 4.0, 6.0 postscald hour (PSH) groups. Rats in each group received routine fluid infusion at 2 PSH, and were sacrificed at 2, 2.5, 4, 6 PSH, respectively. Then the intestinal tissue of the rats was harvested for the detection of the expression of c-fos, PCNA and Bax., Results: The expression of c-fos, PCNA and Bax at 2.0 PSH group (65.8 +/- 4.2%, 74.5 +/- 2.4%, 26.3 +/- 5.7%, respectively) significantly increased when compared with those in 2.5 PSH group (92.4 +/- 5.7%, 85.6 +/- 4.5%, 67.1 +/- 6.6%, respectively) (P < 0.01). The expression of 3 genes increased dramatically at 2.5 and 4.0 PSH, and reached the peak at 2.5 PSH. There was no obvious difference in the gene expression between 4 PSH and 2 PSH groups., Conclusion: The expression of apoptotic genes in the intestinal tissue of scalded rats increased significantly during early resuscitation stage after burn injury.

Objective: It was reported previously that genistein could inhibit proliferation of human ovarian carcinoma cell line SKOV(3), but mechanism was not clear. There is a close relationship between EGFR mediated signal transduction pathway and the development of ovarian tumor. This study aimed to investigate the effects of genistein on the EGFR mediated signal transduction pathway and to clarify its mechanisms of proliferation inhibition on human ovarian carcinoma cell line SKOV(3) and its xenograft in nude mice., Methods: The expression of c-erbB-2 protein was determined using immunocytochemistry. The expressions of c-jun and c-fos protein were determined using Western blotting. The expression of c-erbB-2, c-raf-1, c-jun and c-fos mRNA were tested by reverse transcription-polymerase chain reaction (RT-PCR)., Results: The expression of c-erbB-2, c-raf-1 and its downstream gene c-jun and c-fos were decreased at mRNA level in the 20 micromol/L genistein group. The expression of c-erbB-2 protein were decreased, its average absorbency (A) were decreased after treatment of SKOV(3) with 20 micromol/L genistein for 48 h, reached at 0.42 +/- 0.02 (P < 0.05). Western blotting demonstrated that the expressions of c-jun and c-fos protein were decreased gradually after being treated with 20 micromol/L genistein for 12 - 72 h., Conclusions: Genistein could down-regulate the expression of two key genes, c-erbB-2 and c-raf-1 at mRNA and protein level in the EGFR mediated signal transduction pathway, and down-regulate the expression of its downstream nuclear transcription factors c-jun and c-fos at mRNA and protein level. It is suggested that interfering the expressions of some key signal molecules in EGFR mediated signal transduction system by genistein may account for its molecular foundation of proliferation inhibition in ovarian carcinoma.

Aim: To observe the behavior in learning and memory and the expression of c-fos gene from the brain of rats induced by beta-AP25-35, and the intervention of ecdysterone, in order to explore the protective mechanism of ecdysterone on the dysfunction of learning and memory of the rat induced by beta-AP25-35., Methods: Microinjection of beta-AP25-35 into hippocampus induced learning and memory dysfunction of rats. The learning and memory of rats were observed by Morris Water Maze. The expression of c-fos gene in the brain was detected by immunohistochemistry., Results: The results of Morris Water Maze showed that after rats were microinjected beta-AP25-35 into hippocampus, the rats in model group took longer latency and searching distance compared with the ones in control group (P < 0.01), and the rats in treated group (ECR 4 mg x kg(-1), ECR 8 mg x kg(-1) and nimodipine 7.2 mg x kg(-1)) took shorter latency and searching distance, especially the ECR 8 mg kg(-1) group (P < 0.01). At the same time, after the 5 days training, there was a higher expression of c-fos in hippocampus and cortex from the rats in control group than that in model group (P < 0.01), but in the treated group, there was a relatively higher expression of c-fos, especially the ECR 8 mg x kg(-1) group (P < 0.01)., Conclusion: Microinjection of beta-AP25-35 into the rat hippocampus resulted in dysfunction of learning and memory. Ecdysterone was shown to improve the learning and memory of the rats and increase the expression of c-fos. Increasing the expression of c-fos is probably one of the most molecular mechanism of its protection.

Objectives: To analyze the expression of transforming growth factor-beta1 (TGF-beta1), cyclin dependent kinase inhibitor (p27) and c-fos in human middle ear cholesteatomas and to investigate the correlation between their expression and the ability of erosion of cholesteatoma., Methods: Immunohistochemical staining (SP method) of 31 cholesteatomas and 11 external ear canal skin samples from patients and 10 external ear canal skin samples from healthful men which were taken intraoperatively, was performed for c-fos, TGF-beta1 and p27 positivity. The signals representing the expression of c-fos, TGF-beta1 and p27 were observed under microscope and scanned into a computer by an image scanner. The gray-scale of positive signals were quantitated by image processing computer., Results: The percentage of positive expression of TGF-beta1 and c-fos in cholesteatoma were 87.1% and 83.9%, respectively. Their expression tended to be increased greatly compared with which in the skins of the control groups. Positive p27 signals were not observed in cholesteatomas and external ear skin tissues. It showed statistically significant correlation between expression of c-fos and the ability of erosion of cholesteatoma. There was correlation between the express ion of TGF-beta1 and the ability of erosion of cholesteatoma too. But there was no correlation between the expression of c-fos and TGF-beta1., Conclusion: The expression of c-fos in cholesteatoma was significally higher compared with which in the skin of external auditory of cholesteatoma patients and healthful men, which indicate that c-fos plays an important role in the hyperproliferative of cholesteatoma. The expression of TGF-beta1 was significant higher in cholesteatoma, which indicate that cytokines such as TGF-beta1 play a great role in the etiology of cholesteatoma.

To observe the effects of Panax Notoginosides (PNS) on up-regulation of AP-1 family transcription factors NF-E2, c-jun and c-fos for exploring intracellular signal pathway of PNS in hematopoietic cells, four human hematopoietic cells lines including myeloid HL-60, erythroid K562, megakaryoid CHRF-288 and Meg-01 were incubated in the presence of PNS for 14 days. The nuclear protein of cells were extracted and analyzed by Western blot with antibodies against NF-E2, c-fos and c-jun. Electrophoretic mobility shift assay (EMSA) was performed by using (32)P labeled AP-1 consensus oligonucleotide which contains binding site for NF-E2, c-jun and c-fos. The results showed that the transcription factors NF-E2, c-jun and c-fos of AP-1 family could be induced by PNS. Western blot demonstrated that the nuclear protein of both NF-E2 and c-jun in four cell lines treated by PNS were increased by 1.5-2.5- and 2.0-3.0-fold over untreated cells respectively. The c-fos protein in three cell lines of K562, CHRF-288 and Meg-01 was also elevated by 2.0-3.0-fold respectively, while c-fos protein in HL-60 cells was no detectable difference after PNS treatment. EMSA results in four cell lines indicated that AP-1 binding activity initiated by PNS was apparently elevated to form higher density band of AP-1-DNA complex. In conclusion, the intracellular transcription regulation initiated by PNS was involved in transcription factors NF-E2, c-jun and c-fos of AP-1 family members, which could play an important role in the up-regulation of genes expression related to proliferation and differentiation of hematopoietic cells.

Objective: To investigate the inhibitory effect of 8-chloroadenodine (8-CLA) on tumor necrosis factor-alpha (TNF-alpha)-induced proto-oncogene expression in retinal pigment epithelial (RPE) cells., Methods: Primary culture and subculture of health bovine RPE cells were established in vitro. RPE cells were treated with tumor necrosis factor TNF-alpha (13.3 mmol/L) with or without 8-CLA (16 micro mol/L) for 30 minutes or 3 hours, respectively. C-fos and c-myc mRNA expression in RPE cells was detected by Northern blot analysis., Results: Normal RPE cells expressed c-fos and c-myc mRNA at a low level. After treatment with TNF-alpha, the expression of c-fos and c-myc mRNA was increased by 3.13 and 1.5 fold, respectively, as compared to untreated cells. 8-CLA decreased TNF-alpha-induced c-fos and c-myc mRNA expression by 25.0% and 29.0%, respectively., Conclusions: 8-CLA can inhibit TNF-alpha-induced c-fos and c-myc mRNA expression in RPE cells. These findings may be useful for exploring new drugs for inhibiting the growth-induced proliferation of RPE.

By means of Fos immunocytochemistry, nicotinamide adenine dinucleotide phosphate-diaphorase (NADPH-d) histochemistry and microinjection methods, the role of nitric oxide synthase (NOS) of dorsal raphe (DR) neurons in the modulation of rats sigmoid pain was studied. The results showed: (1) Rats exhibited aversive behavioral responses related to visceral pain after injecting formalin into the sigmoid wall. NOS neurons in DR were up-regulated, in addition, about 8% of NOS-labeled neurons were Fos positive. By contrast, there were no Fos/NOS double-labeled neurons in the control group. (2) Formalin-induced sigmoid pain scores and the expression of Fos in the spinal cord at S1 segment were decreased after microinjecting L-NAME into the DR. These findings suggest that NOS neurons are involved in the modulation of formalin-induced sigmoid pain and that NO may play an important role in the transmission of visceral nociceptive message in the midbrain.

Objective: To observe the effect of lead on the expression of c-fos mRNA in hippocampus and cerebellum and the ability of learning and memory in rat, and to observe the antagonistic action of Gastrodia elata and E-gelatin on the effect mentioned above., Methods: Rats were exposed to lead acetate (0.2 g x kg(-1) x d(-1) and 0.1 g x kg(-1) x d(-1)). The single and combined administration of Gastrodia elata (4 g x kg(-1) x d(-1)) and E-gelatin (1 g x kg(-1) x d(-1)) were conducted at the same time. Blood lead concentration in rats were measured. The ability of learning and memory by Y-maze test were examined. The expression of c-fos mRNA in hippocampus and cerebellum during Y-maze test were observed by in situ hybridization (ISH)., Results: (1) Blood lead concentrations were significantly increased in both high and low doses of lead-exposed rats (P < 0.01). But there were no differences among high dose groups or low dose groups (P > 0.05). (2) In Y-maze test, the number of electric stroke during learning in lead-exposed group was significantly increased (P < 0.01) while that in Gastrodia elata and E-gelatin groups was significantly decreased (P < 0.05), and that in combined use group was more significantly decreased (P < 0.01). (3) There were much more deep-colored c-fos positive cells in CA3 area of hippocampus in low dose of Pb-exposed with Gastrodia elata + E-gelatin group. These cells were also found in high Pb with combined use or single use group, but which were not so densely distributed as the former. And they were hardly found in high and low doses of Pb alone groups. The changes of expression of c-fos cells in cerebellam were similar to those in hippocampus., Conclusion: The down regulation of c-fos expression may be one of the molecular mechanism of lead-induced impairment of learning and memory. Gastrodia elata and E-gelatin may antagonize the effect of lead on c-fos expression, and combined use of both drugs may potentiate the antagonism.

Objective: To study the mechanism of Shu Di-huang in improving the function of learning and memory., Method: On the rats model with thalamic arcuate nucleus dameged by MSG, the improving function of Shu Di-huang on learning and memory was observed by step down task and Morris water maze task, and the expression of c-fos and NGF in hippocampi was observed by immunohistochemical means., Result: Shu Di-huang could decrease the times of mistakes and prolong the incubation period in step down task, and shorten the incubation period of seeking the platform, and improve the percentage rate through the platform position in Morris water maze task. Shu Di-huang also increase the expression of hippocampal NGF, c-fos., Conclusion: Shu Di-huang can improve the function of learning and memory of MSG rats, and its mechanism may be related with the increase of the expression of hippocampal c-fos and NGF.

Objective: To determine the effects of Varglaucocalyx on c-fos gene expression during global myocardial ischemia-reperfusion., Method: Forty Wistar rats were divided into 5 groups: group N as control; group CN as ischemia-reperfusion control and group XH, XM and XL treated with Varglaucocalyx 5%, 1%, 0.5% respectively prior to ischemia-reperfusion. The isolated rat hearts were perfused in condition of constant temperature and pressure, and then the left ventricular myocardiums were extracted for use. The expression of c-fos protein was detected by immunochemical method. The expression of c-fos protein were quantified by using computer image analysis system., Result: Compared with the values of group N, protein expressions relative area of c-fos gene (PERA) were increased significantly in group CN, XH, XM, XL(P < 0.01), but decreased significantly in group XH, XM, XL, compared with those of group CN (P < 0.05). The PERA of c-fos gene in group XM, XL were significantly lower than in group XH (P < 0.01), and the PERA of c-fos gene in group XM were lower than in group XL(P < 0.05)., Conclusion: Varglaucocalyx can effectively depress the expression of c-fos gene in myocardium which may account for its protection against myocardial ischemia-reperfusion injury, and the middle and the low concentrations of Varglaucocalyx are more effective than the high concentrations.

Aim: To investigate the effects of anoxia/reoxygenation on Fos and Jun expression and apoptosis in cultured rat hippocampal neurons., Methods: The hippocampal neurons cultured for 12 d were exposed to anoxia environment (90% N2 + 10% CO2) for 4 h and then reoxygenated for 24 h and 72 h. The neurons were immunocytochemically stained using the antiserum against Fos and Jun, and the apoptosis were detected by using the terminal deoxynucleotidyl transferase mediated biotinylated deoxyuridine triphosphate nickel end labeling (TUNEL) method and flow cytometric analysis., Results: The percentage of Fos and Jun positive neurons and apoptosis neurons in cultured hippocampal neurons after anoxia/reoxygenation increased than those in control., Conclusion: The occurrence of neurons apoptosis is related to the increase in Fos and Jun expression in cultured hippocampal neurons after anoxia/reoxygenation.

Objective: To observe the time course and tissue distribution of c-fos, c-myc and basic fibroblast growth factor(bFGF) genes and their proteins in burned skin, and explore the possible network regulation mechanisms of c-fos, c-myc and bFGF in wound healing and the role of the protein kinase C pathway involved in signal transduction among these growth-related factors., Methods: The study was carried out on 188 Wistar rats. Animal model with 30% partial thickness scald injury was made and all rats were randomly divided into several groups: normal control (n = 8), injured control (n = 36), anti-c-fos (n = 36), bFGF (n = 36), 1-5-Isoquinolinyl-sulfony-2methylpiperazine (H7), and 2, 3-Butanedione monoxime (BDM) (n = 36). In situ hybridization, reverse transcription polymerase chain reaction (RT-PCR) and streptavidin peroxidase (SP) immunohistochemistry methods were used to detect the gene and protein expression of c-fos, c-myc and bFGF in the wounded tissues., Results: (1) The first appeared induction of growth-related gene was c-fos, the second bFGF, and the last c-myc. They were peaked at 3 h, 1 d and 3 d postburn with values of 14.5 +/- 1.3, t = 13.306; 0.15 +/- 0.04, t = 3.460 and 0.11 +/- 0.05, t = 2.292, respectively (P < 0.05). (2) Treatment with c-fos antibody decreased the expression of these three growth-related factors when compared with that in the controls. There were a 80% decrease in c-myc and a 85% decrease in bFGF. (3) Treatment with H7 inhibited the gene and protein expression of c-fos and bFGF. The peak times of c-myc gene and protein were delayed to 6 hours post injury. Treatment with BDM induced an earlier expression of c-myc mRNA at 6 hours, and increased the gene and protein expressions of c-fos and bFGF. The total amount of their values was increased to 0.23 +/- 0.07, t = 2.942 and 0.69 +/- 0.07, t = 5.134 (P < 0.01)., Conclusions: Thermal injury can induce a series of growth-related gene expression showing a phasic control and regional distribution. c-fos plays an important role in wound healing process. Protein kinase C pathway may repair wound.

Changes in behaviour relevant to the vestibular system were studied in Long-Evans rats which were fertilized, born and housed in 2 acceleration of gravity for 4 months and thereafter exposed to 1 acceleration of gravity, and expression of Fos protein in the brain stem was examined. Data from the hypergravity rats were compared respectively with those from the rotation group and the labyrinthectomized group. Static and locomotion modes of the hypergravity rats were changed, tension of extensor was enhanced and the abilities in locomotion equalization and orientation in swimming and air-righting response were reduced. The adaptation process varied with different behaviours. The time for recovery of the ability of orientating in swimming was the longest, taking more than 1 month. The Fos protein expression provides a useful tool for mapping brain functional activities after sensory stimulation, showing a low basal level in normal and labyrinthectomized groups. The hypergravity rats, on the other hand, exhibited more Fos-positive cells in the superior colliculus, inferior colliculus, periaqueductal gray, raphe dorsal nucleus and solitary nucleus. In contrast, the inferior olivary nuclei, locus coeruleus and vestibular nuclei were not strongly labeled. These spatial patterns of Fos expression suggest that a decrease in gravity-inertial force may activate a neural pathway different from the vestibulo-olivar pathways activated by an increase in gravity-inertial force.

Objective: This paper is aimed to explore the mechanisms of brain development abnormality induced by alcohol., Methods: Astrocytes and oligodendrocytes of 19-day rat embryo were exploited and cultured in vitro, and alcohol and its metabolite product (acetaldehyde) were added to DMEMF(12) medium. After different exposure times, c-fos expression of astrocytes and oligodendrocytes was measured by the immunocytochemistry technique., Results: Changes in c-fos gene expression induced by alcohol and acetaldehyde was time and dose dependent. After 1 hr exposure, alcohol and acetaldehyde affected c-fos gene expression in two kinds of neuralglia. C-fos positive expression reached peak value after 2 hr, but recovered after 72 hr and showed special time phase expression., Conclusions: Alcohol and acetaldehyde cause abnormal increase of c-fos gene expression in astrocytes and oligodendrocytes. This abnormal expression may play an important role in abnormal brain development induced by alcohol.

Objective: To explore the characteristics and regularity of the expression of c-fos and c-jun genes in hypertrophic scar and chronic ulcer tissues and their relationship to different tissue restoration., Methods: Tissue samples of hypertrophic scars were harvested from 16 cases of patients after burns and chronic cutaneous ulcers during operation together with the normal skin (n = 5) of the same patients as control. ABC method was employed to detect the gene expression of both c- fos and c-jun in above samples., Results: The positive expression of c-fos and c-jun gene was found in epithelial basal cells and some subcutaneous fibroblasts in normal skin. But the expression of c-jun was weaker than that of c-fos in above tissues. A strong positive expression of c-fos and c-jun genes was found mainly in fibroblasts in the hypertrophic scar. But the combined expression of both tumor genes was most often found in the capillary endothelium, some inflammatory cells and the cytoplasm of fibroblasts in ulcer tissue., Conclusion: The results indicated that the amount and location of the expression of c-fos and c-jun genes were different in the three kinds of tissues, suggesting that these two tumor genes may play important roles in wound healing modulation.

mRNA isolated from 2/3 partially hepatectomied rats was used as a tester for representational difference analysis (RDA). The subtracted tester cDNA was cloned into a T vector and a rat regeneration liver specific EST pool was constructed, which contained about 30000 independent clones. A sequence analysis of 52 clones randomly picked up from this pool indicated that the liver regeneration specific sequences were enriched, and the results of RNA blots revealed some novel genes in association with liver regeneration.

The present study was to investigate the effects of angiotensin II on c-fos mRNA expression and protein synthesis in cultured neonatal rat myocardial cells. The results showed that angiotensin II induced c-fos mRNA expression, increased protein content in a dose-dependent manner and stimulated 3H-leucine incorporation rate. All these effects were blocked by angiotensin II receptor antagonist saralasin. The angiotensin II-induced expression of c-fos gene was also blocked by Ca2+ channel antagonist nicardipine.

The effects of endothelin-1 (ET-1) on pulmonary surfactant (PS) synthesis of cultured alveolar type II cells (AT II) were observed. The role of c-fos gene in cellular signal transduction of ET-1 was studied by antisense technology. The results showed that: (1) ET-1 enhanced [3H] choline incorporation into AT II cells in a dose-dependent manner. (2) Protein kinase (PKC) activator PMA increased [3H] choline incorporation into AT II cells, while PKC inhibitor H7 inhibited the stimulating effect of ET-1. (3) Both ET-1 and PMA could increase the level of c-Fos protein, and H7 and c-fos antisense oligonucleotides (AS ODN) could inhibit the effects induced by ET-1 on Fos protein expression and [3H] choline incorporation. (4) The release of lactic dehydrogenase (LDH) was not different among control, ET-1, antisense oligonucleotides and sense oligonucleotides groups. The above results demonstrated that ET-1 can enhance PS synthesis of AT II cells and ET-1 stimulating the expression of c-fos gene mediated by PKC is a major signal transduction pathway of modulating PS synthesis.

Employing immunohistochemical staining for FOS protein, which is the expression product of c-fos proto-oncogene, the role of substance P receptor (SPR) in noxious information transmission at peripheral terminals of the dorsal root ganglion cells was investigated by means of a selective SPR antagonist L668, 169 and agonist Sar-SP. Unilateral injection of L668, 169 (10(-4) mol/L) into the plantar of hindpaw 10 min before injection of 4% formalin, the number of FOS-like immunoreactive (LI) neurons in the superficial laminae of dorsal horn was significantly decreased, but the changes were not obvious in the deeper laminae. Smaller doses of L668, 169 (10(-5), 10(-6) mol/L) were almost ineffective on FOS-LI neurons in both the superficial and the deeper laminae. However, Sar-SP (10(-4) mol/L) or formalin did result in the expression of c-fos gene in the superficial laminae of the dorsal horn. These results indicated that SP might contribute to the transmission of nociceptive information and induce noxious sensation, at least in part by activating SPR in peripheral terminals of the dorsal root ganglion cells.

Effects of recombinant human interleukin-1 beta (rhIL-1 beta) on the c-fos expression of cultured rat hippocampal neurons in vitro induced by anoxia were studied by using an immunohistochemical method. The results showed that the percentage and the mean optical density of the Fos-positive neuronal nuclei in cultured hippocampal neurons increased markedly as anoxia prolonged, while those in hippocampal neurons pretreated with rhIL-1 beta were significantly lower than those of control. The results indicate that anoxia can induce c-fos expression of cultured rat hippocampal neurons in vitro and this can be inhibited by rhIL-1 beta, suggesting that rhIL-1 beta may protect neurons from damage in a certain degree during anoxia.

Objective: To investigate the effect of epidermal growth factor (EGF) on cultured trabecular cells., Methods: Molecular hybridization technique was used to investigate the effect of EGF on c-fos expression and its induction of bovine trabecular cells in vitro, and 3H-TdR incorporation method was applied to study the synthesis of DNA., Results: EGF enhanced the incorporation of 3H-TdR into trabecular cells at concentrations ranging from 20-150 ng/ml (P < 0.001). Compared with control, the expression of c-fos appeared at 0.5 hour and 1 hour after stimulation, and did not exist till 2 hr. The level of c-fos expression in cells relied on the concentration of EGF., Conclusion: Our results suggest that EGF stimulate trabecular cell proliferation at least in part by the regulation of the c-fos gene and its nuclear protein.

In this study, the role of angiotensin II (Ang II) receptor, Ca2+ in the Ang II-stimulated neoeatal myocytes protein synthesis were investigated and the effect of Ang II on expression of c-fos gene was observed. The results showed that the stimulatory effect of Ang II on protein synthesis was blocked by the Ang II antagonist-[Sar1 Ile8] Ang II. When verapamil, EG-TA, dantrolene, and Fura-2/AM, were added to the medium, the 3H-leucine incorporations stimulated by Ang II were reduced by 17%, 19%, 22%, and 27%. Using calcium ionophore-A23187 did not stimulate protein synthesis, but enhanced Ang II-induced 3H-leucine incorporation. In addition, Ang II could induce expression of c-fos gene. These results indicated that the hypertrophic effect of Ang II on the myocytes was mediated by Ang II receptor and depended on increase in [Ca2+]i and may be associated with enhanced expression of c-fos.

Atherosclerosis (AS) is characterized by the proliferation of the smooth muscle cells (SMC) in the arterial wall. Its pathogenesis might be associated with overexpression of oncogenes in SMC. Gorden and Barrett et al found that sis mRNA level elevated in human atherosclerotic plaques 5-12 fold above level present in normal artery. But the transcriptional expression of c-fos, c-myc, c-jun, H-ras, v-erb-B oncogenes and Rb antioncogene in atherosclerotic lesion has not yet been reported. A study on these oncogenes and Rb gene expression in artherosclerotic lesions in rabbits fed on high cholesterol diet were assayed by the dot blot hybridization using alpha-32P-labelled oncogenes and Rb gene fragments as the probes. After fed with the high cholesterol diet for six months, the plasma cholesterol levels in AS rabbits were significantly increased (1300 +/- 240 mg/dl vs 67.1 +/- 11.5 mg/dl). The atherosclerotic plaques covered 91% +/- 11% of the intimal aortic surface of aorta thoracalis. The results showed that the atherosclerotic plaques contained 3-4 fold more v-sis, c-fos and c-myc mRNA (P < 0.01), 2 fold more c-jun and H-ras mRNA (P < 0.01), and less Rb mRNA (P < 0.05) than those in the normal aortic arteries. But the expression of v-erb-B gene in atherosclerotic plaques remained unchanged. These results indicate that the abnormal expression of v-sis, c-myc, c-fos, c-jun, and H-ras oncogenes and Rb antioncogene may play an important role in arterial SMC proliferation and pathogenesis of atherosclerosis.

Objective: This study was designed to test the hypothesis that inflammatory cells deposited on the surface of implanted intraocular lens stimulate the proliferation of residual lens epithelial cells., Methods: Immunocytochemical ABC methods with purified anti-human Fos protein serum antibody was used to stain the cultured rabbit lens epithelial cells incubated with rabbit macrophages and macrophage-conditioned medium (MCM)., Results: The lens epithelial cell growth was faster in the cultures with macrophages and MCM than in the controls. Fos protein positive staining was found in the nuclei of epithelial cells cultured with macrophages for 4 hours, and of the cells with MCM for one hour; whereas the staining was negative in the cells of control cultures., Conclusion: Macrophages promote c-fos oncogene expression in the lens epithelial cells, that might be mediated by bioactive factors secreted by macrophages.

In the present study the effect of pressure overload on the expression of protooncogene c-fos in the left ventricle was investigated in rats with abdominal aorta constriction. It was found that a remarkable expression of c-fos was induced by pressure overload and the expression was greatly attenuated by angiotensin converting enzyme inhibitor captopril. In the pressure overload group the angiotensinogen mRNA level was found increased. The above results suggest that angiotensin II is involved in the expression of c-fos due to pressure overload.

In this study, Sprague-Dawley (S.D.) rats were pretreated with kainic acid (KA, 10 mg/kg, i. sc.) 72 days before either deep prepyriform cortex (DPC) kindling or injection of the same dose of KA. The results showed that such pretreatment accelerated the process of kindling, and the KA-induced seizures appeared more severe in behaviours. c-Fos-immunoreactivity (c-Fos-ir) was used to demonstrate the neuronal activity in central nervous system during the provocative dose of KA-induced seizure, as comparing with the control which received normal saline of KA 72 days ago. The results indicated that, the transmission pathways in two groups were just the same; but the time courses of c-fos and c-jun expression in KA pretreated group were accelerated asynchronously; and the synthesis of the proenkephalin mRNA in the Ent was apparently up-regulated. It is suggested that, the long-lasting increase in susceptibility to seizure induced by a single administration of KA may be related to the acceleration of the expression of c-fos/jun and the early onset of the expression of proenkephalin mRNA.

The effect of alpha 1-Adrenoceptor (alpha 1-AR) and its subtypes, alpha 1A and alpha 1B, activation on the proliferation of cultured vascular smooth muscle cells (VSMC) was studied by [3H]-thymidine (3H-TdR) incorporation and in situ hybridization. Norepinephrine (NE) promotes DNA synthesis of VSMC. The action was induced by activation of alpha 1A-AR subtype and increase of c-fos gene expression. However, the DNA synthesis was inhibited by activation of alpha 1B-AR subtype. There was a synergetic effect on VSMC DNA synthesis between NE and neuropeptide Y (NPY). But only additional effect was found between NE and Ang II. More over, it was found that alpha 1B-AR subtype showed significant constitutive inhibitory effect of VSMC DNA synthesis.

Dot blot showed that the expression of proto-oncogene c-fos was inhibited in lymphocytes from old mice (20-24 months). In order to measure the effect of aging on signal transduction, we separated T cells by passage of spleen lymphocytes through long nylon fiber columns. Con A-induced [3H] TdR incorperation in cells from old mice was lower than that from young mice (2 months). The maximum level of [3H]TdR incorperation of old mouse T cells was only 22% of that of young mouse T cells. When T cells were stimulated with the combination of a phorber ester (PMA) and a calcium ionophore (ionomycin), [3H]TdR incorperation remained depressed in old mouse T cells. Further, cytosolic free calcium level was measured by monitoring fluoresence intensity in fura-2/AM loaded T cells. At 10 minutes after con A stimulation, the concentration of cytosolic free calcium ([Ca2+]) in old mouse T cells elevated to 273 x 10(-9)mol/L, while [Ca2+] in young mouse T cells markedly increased to 637 x 10(-9)mol/L. When T cells were stimulated with the combination of PMA and ionomycin, at 7 minutes, [Ca2+] in old mouse T cells elevated to 790 x 10(-9)mol/L, while [Ca2+] in young mouse T cells markedly increased up to 2190 x 10(-9)mol/L.

Using the techniques of immunohistochemistry, Northern blotting and in situ hybridization, we have found that electroacupuncture (2/15Hz) accelerated the expression of mRNA and protein synthesis of immediate early genes c-fos, c-jun as well as proenkephalin gene in rat central nervous system (CNS). Northern hybridization revealed that EA stimulation induced c-fos gene expression within 1-2 h, followed by PENK gene expression which peaked at 48h. Morphological study demonstrated that the sites of c-fos, c-jun and PENK mRNA expression and protein synthesis coincide with each other in the CNS. The results suggest that Fos/Jun may function as the transcription regulator of PENK gene.

We used well-cultured human embryo retinal pigment epithelial (RPE) cells to establish a light-damaged RPE cell model. There was no onco-gene c-fos expression in RPE cells cultured under normal condition. Immediately after 30 minutes of light exposure, onco-gene c-fos expression occurred in the RPE cells. The expression reached the highest level 1.5 hours after light exposure and disappeared 4 hours later. Taurine and gamma-interferon in different concentrations could restrain onco-gene c-fos expression in light damaged RPE cells. The restraint effects were of concentration dependence.

The modifications of gene expression by tumor promoters were analyzed in vitro and in vivo. The results of slot blot hybridizations showed that tumor promoter TPA induced c-fos and c-myc expressions in mouse fibroblast cell line BALB/3T3 and rat liver, decreased the levels of Rb RNA in BALB/3T3 cell line and of alpha 1-I3 RNA in rat liver. It was also demonstrated that tumor promoter phenobarbital influenced c-fos and c-myc expressions and decreased alpha 1I3 mRNA level in rat liver during a long term experiment. Phenobarbital was found to have no effect on c-fos and c-myc expressions in rat liver during a short experiment. Tumor promoters induced the expressions of c-fos and c-myc which were positively-related to cancer formation and inhibited the expressions of Rb and alpha 1-I3 which were negatively-related to cancer formation. This implied that tumor promotion played an important role in cancer development and tumor promoters exerted their effects selectively according to the attributes of different genes.

In the present study, the effects of angiotension II on the expression of protooncogene c-fos and c-myc in the left ventricle were investigated on Langedorff heart preparations. It was observed that angiotensin induced both c-fos and c-myc expression in a dose-dependent manner and the c-fos expression showed an earlier appearance than c-myc. All these induced expressions were blocked by a Angiotensin II receptor antagonist saralasin. The Angiotensin II induced expression of c-fos was also blocked by TTX, but the c-myc gene expression was unaffected.

To explore the mechanisms by which angiotensin converting enzyme inhibitor (ACEI) prevents the development of left ventricular hypertrophy (LVH), captopril (Cap 100 mg.kg-1/d was administered orally to male spontaneously hypertensive rats from intrauterine period to 16 weeks of age. Male and age-matched untreated WKY rats and SHR were used as controls. Experiments were performed at 40 weeks of age. SBP, left ventricular weight to body weight ratio (LVW/BW), myocardial hydroxyproline (Hypro) and norepinephrine (NE) were determined. The levels of c-myc and c-fos mRNA in the left ventricle were measured by Northern blot. Early-onset Cap therapy significantly decreased SBP at 16 weeks of age. After discontinuance of treatment for 24 weeks, SBP of SHRcap was still maintained at a level lower than that of untreated SHR. LVW/BW and Hypro in SHR cap were markedly reduced. The expression of myocardial c-myc mRNA (n = 5) was decreased by 72% in SHRcap compared with that in the untreated SHR, but the expression of c-fos mRNA (n = 7) and NE was not different between the untreated SHR, SHRcap and WKY rats. These results indicate that early Cap treatment may permanently prevent the development of hypertension, inhibit myocardial hypertrophy (MH), and interstitial fibrosis. Furthermore, the prevention of MH is associated with a decrease in myocardial c-myc mRNA levels, and the development and regression of MH may be irrelevant to proto-oncogene c-fos expression.

4-hydroxycarbophenyl retiamide (R II) is a new synthetic analogue of retinol, but with lower toxicity than retinoic acid. We studied its induction effects and its effects on some malignant phenotypes of the MFC cell line. The mechanism of these effects was also explored. MFC cells were grown in complete RPMI 1640 medium supplemented with 10(-5) mol/L R II for five passages. By then the cell growth rate slowed down; the rate of 3H-TdR incorporation and the colony-forming capacity of MFC cells decreased; morphologically, the cells became epithelial rather than fibroblastic with various degrees of polarization. Further investigation about the mechanism of these changes was also undergone. First by flow cytometry, it was shown that the R II-treated cells were retained in G1 phase. Second, dot blot hybridization showed a decrease of more than 61% of c-myc mRNA and an increase of more than 52% of v-fos mRNA. The major chromosome distribution changed from 54-56 to 46-54 with an increase in diploid. Scanning microscopic examination showed that the R II-treated cells were covered by numerous microvilli and pseudopodia with round terminal expansion in contrast to the ruffle protrusions and leaf-like pseudopodia of control cells. All the results suggested that R II could reverse some malignant phenotypes of MFC cells.

The promyelocytic leukemic cell line HL-60 with 20-200U/ml of low-dose rhTNF-a cultured in liquid culture system in vitro was used to observe the effect on HL-60 by TNF. TNF within dose of 50-200 U/ml can induce HL-60 cell differentiation along the monocytic-macrophage pathway, and inhibit HL-60 cell proliferation. The total RNA of HL-60 cell was used to hybrize to v-myc or v-fos probe by dot blot. We detected the expression changes of c-myc or c-fos proto-oncogene by 1-100U/ml of TNF inducing HL-60 cell for 1-12 hours. TNF could regulate the level of c-myc or c-fos mRNA, the transcription of c-myc was inhibited remarkdly, and the expression of c-fos was increased early. The results indicated that TNF in low-dose have effect on inducing HL-60 cell differentiation and regulating expression of multioncogene.

We use NMDA to induce expression of c-fos mRNA as a marker to observe the activity of NMDA receptor in neurons during development, and compare the activity of NMDA receptor between audiogenic epilepsy -prone (P77PMC) and audiogenic epilepsy resistant rats brain. In primary culture of rats cerebral cortical neurons NMDA induced c-fos mRNA expression exhibits dose and time-dependent changes, which can be prevented by antagonists. During the development of neurons, the NMDA -induced c-fos mRNA expression reaches a maximum at day 24. NMDA-induced c-fos mRNA expression of P77PMC rats is higher than that of controls during 6 to 24 days in vitro with significant difference (P < 0.05) at day 18. To present changes in c-fos mRNA expression induced by NMDA in cultured P77PMC rat cortical neurons may be one of the factors related to susceptibility of epilepsy in P77PMC rats.

The model of balloon angioplasty (BA) was founded in rabbit abdominal aorta. In situ hybridization was used with the probes of oncogenes c-fos, c-myc and N-ras labeled by digoxin in vessel segments after BA and with the probes of oncogenes c-fos, c-myc, and N-ras labeled by biotin in smooth muscle cell (SMC) irritated by cultured medium of vessel segments after BA. Overexpression of c-fos, c-myc and N-ras oncogenes occurred in vessel segments after BA mainly in atherosclerotic plaques. There was expression of oncogene in normal vessel segments. Overexpression appeared in the over-proliferative SMC irritated by cultured medium of vessel segments after BA. A expression of N-ras occurred on the membrane of cellular nucleus. There was no expression of oncogenes in the normal SMC of control group. Overexpression could be partly inhibited by interferon-gamma.

After the experimental kitten eyes were exposed to stimulation by the moving sinusoidal grating, the fos proteins, products of c-fos genetic expression in the nuclei of excited neurons in layer IV of the visual cortex area 17, were stained with the immunocytochemical ABC technique. The changes in number and grey scale of the c-fos immunopositive neurons of normal, monocular strabismic and monocular deprived eyes were processed by the computer image analysis system. The results indicated that (1) the PVEP of amblyopic cats was consistent with the dysplasia of visual cortex; and (2) the pathophysiologic defects in visual cortex of the amblyopic cats did have a molecular chemoneurological basis.

Using dot blot methods to identify the relationship between the oncogene expression and monosomy of chromosome No 15 in BHLB4 and their changes after induced differentiation, the results indicated that in Clone-1 (high frequency of chromosome No 15 monosomy) C-myc, H-ras, K-ras, N-ras and C-fos expression was higher than that in BHLB4. In Clone-4 (low frequency of chromosome No 15 monosomy), N-ras expression was lower than that in BHLB4. Decreased expression of C-myc, H-ras, and N-ras oncogenes could also be observed during cell differentiation induced by buta acid. It is possible that an antioncogene located on chromosome No 15 regulates oncogene expression, and differentiation agents would have obvious effects on it.