Objective To explore the regulating mechanism of hepatic injury in obstructive jaundice (OJ). Methods①Rat hepatocytes were isolated by in situ collagenase perfusion and primary culture. Hepatocytes were pretreated with various concentrations of protein kinase C (PKC) agonist parsmeae (PMA) and inhibitor chelerythrine for 20 min. After pretreatment, 50 μmol/L glycochenodeoxycholate (GCDC) was added. Cells were next detected by FCM and TUNEL.②Experimental obstructive jaundice was induced by double ligation of the bile duct (BDL), BDL for 3, 7, 14, 21days.We detected apoptotic status in liver with TUNEL and PKC protein in liver with immunohistochemistry method. Results①PMA increased GCDCinduced apoptosis and chelerythrine decreased GCDCinduced apoptosis in a concentrationdependent manner. ②The apoptotic rate of liver was related to time of OJ. Apoptosis index (AI) was the highest in 14day bile duct ligation. The ber PKC expression, the more number of apoptotic cells in OJ.Conclusion PKC takes part in the regulation and the occurrence and progression of hepatic injury in OJ.
Abstract： Objective To investigate the mechanism of protein kinase C(PKC) in immature myocardial ischemic preconditioning in order to further its clinical applicability. Methods Langendorff perfusion heart models of 24 rabbits were set up and they were randomly divided into 4 groups: ischemic reperfusion group (I/R group), myocardial ischemic preconditioning group (MIP group), chelerythrine group (CLT group) and protein kinase C group (PKC group). The emodynamics, biochemistry and myocardial ultrastructure were observed. Results The heart function recovery and myocardial water content in the MIP and the PKC groups were better than those of the I/R and the CLT groups (Plt;0.01). The adenosine triphosphate (ATP) content, superoxide dismutase activity, mitochondrial Ca2+-ATPase activity and synthesizing ATP activity of mitochondria in the MIP and the PKC groups were significantly higher than those of the I/R and the CLT groups (Plt;0.01). The dehydrogenase and creatine kinase leakage, malondialdehyde content, myocardial cell Ca2+ content and mitochondrial Ca2+ content in the MIP and the PKC groups were significantly lower than those of the I/R and the CLT groups (Plt;0.01). The myocardial ultrastructure injuries in the MIP and the PKC groups were less than that of the I/R and the CLT groups. Conclusion Myocardial ischemic preconditioning plays an important role in protecting immature myocardium, which is probably realized by the activation of PKC.
Objective To investigate the alteration of protein kinase C (PKC) and endothelin system in early diabetic rats, and the effect of specific PKC inhibitor on the expression of retinal endothelin-1 (ET-1). Methods The rats model with streptozotocin(STZ)-induced diabetes were set up. The expression of retinal PKC was detected by enzyme-linked immunoabsorbent assay (ELISA). The expression of retinal ET-1, ET-3, ET-A and ET-B receptor mRNA was determined by semi-quantitative reverse transcription-polymerase chain reaction (RT-PCR). The alteration of retinal ET-1 mRNA after intravitreal injection of PKC inhibitor GF109203X in diabetic rats was also observed. Results The activities of membranous PKC were significantly increased in 2-week diabetic rats compared with that in normal rats（t=3.296 , P=0.008）, while activities of cytosolic PKC were unchangeable（t=0.138, P=0.894）. The expression of retinal ET-1 mRNA was significantly increased（P=0.008）, while no change was found in expression of ET-3, ET-A and ET-B mRNA（P=0.918，P=0.889，P=0.500）. After intravitreal in jection of 10-5、10-6、10-7 mol/L PKC inhibitor GF109203X in diabetic rats, the expression of retinal ET-1 mRNA was decreased in a dose-dependent manner compared with the control rats. Conclusion Activation of PKC and increased expression of ET-1 could be found in the retina of early diabetic rats, and PKC inhibitor could inhibit the expression of retinal ET-1. (Chin J Ocul Fundus Dis，2004，20：168-171)
PURPOSE:To evaluate the activitv of protein kinase C(PKC) in response to retinal photochemical insult in rat. Furthermore, to investigate the effect of dexamethasone(DXM ) on PKC activity. METHODS :The experiments were performed on 48 SI') rats whieh were separated into two groups,control and treated groups,and the latter received daily intraperitoneal injections of DXM (1 mg/kg)for 5 consecutive days,starting 3 days before light exposure. The animals were continually exposed to green fluorescent light (510nm~560nm) with an illuminance level of (1 900plusmn;106.9)lx for 24 hrs.The retinal enzyme activity of PKC was tested at 6 hrs,1 day,3 days,7 days,and 14 days after light exposure respectively. RESULTS:In animal models,PKC activity showed a transient increase in both groups at 6 hrs after light exposure and then decrease persistently there alter. The activity of PKC was unresponsive to DXM intervention. CONCLUSIONS :These results suggested that the persistent lower PKC activity might result in disturbance of retinal function in rat retinal photochemical injury. （Chin J Ocul Fundus Dis,1997,13: 78-80）
ObjectiveThe purpose of this study was to explore the expression of Corticotropin releasing hormone (CRH), Corticotropin releasing hormone receptor 1 (CRHR1), Protein kinase C (PKC) in epileptogenic zone of Infantile spasm (IS).MethodsCollected 17 cases of tissues of IS patients from operation and 6 cases of normal brain tissues from clinical autopsy during June 2011 to June 2014. Westen blot was used to detected the protein expression of CRH, CRHR1, PKC. PCR was used to exam the mRNA expression of CRH, CRHR1, PKC. Immunohistochemistry and fluorescenceimmuno assay were used to detect the expression of CRH, CRHR1, PKC.ResultsThe mRNA expression of CRH and CRHR1 in IS group are higher than control group, and the protein expression of CRH and CRHR1 in IS group are higher than control group. CRH are slightly expressed in the controls, medium and strong expressed in IS, CRH and NF200 both expressed in IS; CRH is negative in GFAP positive astrocyte; CRH is negative in HLA positive microglial cell. CRHR1 are slightly and medium expressed in the controls, medium and strong expressed in IS, CRHR1 and NF200 both expressed in IS; CRHR1 and GFAP are both positive in astrocyte; CRHR1 and HLA are both positive in microglial cell. PKC are slightly and medium expressed in the controls, medium and strong expressed in IS, PKC and NF200 both expressed in IS; PKC and GFAP are both positive in astrocyte; PKC and HLA are both positive in microglial cell. Spearman analysis showed positive correlation between the expression of CRH, CRHR1, PKC with epileptic spasm in IS patients, as well as positive correlation between PKC with CRHR1.ConclusionsOver expression of CRH, CRHR1, PKC with epileptic spasm in IS patients were positive related with epileptic seizure in IS patients, indicated that CRH signal pathway is related with IS pathogenesis.