The Effect of Shenqi Jianxin Formula （参芪健心方） on Cardiomyocyte Pyroptosis in Chronic Heart Failure Model Rats Based on the NLRP3/Caspase-1 Signaling Pathway / 中医杂志

ObjectiveTo investigate the possible mechanism of Shenqi Jianxin Formula （参芪健心方） in the treatment of chronic heart failure （CHF） from the perspective of pyroptosis. MethodsFifty-two rats were randomly divided into sham operation group （n=8） and modeling group （n=44）. In the modeling group， the anterior descending branch of the left coronary artery was ligated to construct CHF rat model. Forty successfully-modelled rats were randomly divided into model group， Entresto group， Shenqi Jianxin Formula group， MCC950 group and the combination group （Shenqi Jianxin Formula plus MCC950）， with 8 rats in each group. In Shenqi Jianxin Formula group， 7.4 g/（kg·d） of Shenqi Jianxin Formula was given by gavage， while in Entresto group， 68 mg/（kg·d） of Entresto suspension was given by gavage； in MCC950 group， MCC950 was injected intraperitoneally with 10 mg/kg once every other day， and in the combination group， 7.4 g/（kg·d） of Shenqi Jianxin Formula was given by gavage， and MCC950 was injected intraperitoneally with 10 mg/kg once every other day； 10 ml/（kg·d） of saline was given by gavage in the sham operation group and the model group. After 3 weeks of continuous intervention， serum brain B-type natriuretic peptide （BNP）， creatine kinase isoenzyme MB （CK-MB）， interleukin 1β （IL-1β）， and interleukin 18 （IL-18） levels were detected by ELISA； HE staining and MASSON staining were used to observe pathological changes in rat myocardium. Except for the Entresto group， western blot technique was used to detect the expression of NOD-like receptor protein 3 （NLRP3）， caspase-1， and apoptosis-associated speck-like protein possessing a caspase-recruiting domain （ASC）； RT-PCR was used to detect the expression of NLRP3 and caspase-1 mRNA. ResultsCompared with the sham operation group， HE staining of rats in the model group showed obvious myocardial injury， while MASSON staining showed increased area of collagen fibrosis， and serum BNP， CK-MB， IL-1β， IL-18， myocardial tissue NLRP3， caspase-1， ASC protein expression and NLRP3， caspase-1 mRNA expression were all elevated （P＜0.05）. Compared with those in the model group， cardiomyocyte injury of rats and collagen fibrosis area were reduced， and serum BNP， CK-MB， IL-1β， and IL-18 contents were all reduced in Shenqi Jianxin Formula group， Entresto group， MCC950 group， and the combination group； except for Entresto group， myocardial tissue NLRP3， caspase-1， ASC protein expression and NLRP3， caspase-1 mRNA expression were reduced in the remaining three medication group （P＜0.05）. Compared with Shenqi Jianxin Formula group， the MCC950 group and the combination group showed decreased serum IL-1β and IL-18 content， collagen fibrosis area， myocardial tissue NLPR3， caspase-1 protein expression， and caspase-1 mRNA expression， and decreased ASC and NLRP3 mRNA expression was shown in the combination group （P＜0.05）. Compared with MCC950 group， collagen fibrosis area was reduced， and serum IL-18 content， NLRP3， caspase-1 mRNA expression were reduced in the combination group （P＜0.05）. ConclusionShenqi Jianxin Formula can effectively improve the myocardial injury and heart failure in rats with CHF， and its mechanism may be related to the inhibition of cardiomyocyte pyroptosis through NLPR3/Caspase-1 pathway to reduce the level of intramyocardial inflammation. The combined use of MCC950 with Shenqi Jianxin Formula could more effectively inhibite myocardial pyroptosis， with better therapeutic result than single use of each part.

Effects of MCC950 on nerve injury in rats with intracerebral hemorrhage / 中国应用生理学杂志

Objective: To investigate the effects of the pyrin domain-containing protein 3 (NLRP3) inflammasome inhibitor MCC950 on nerve injury in rats with intracerebral hemorrhage(ICH). Methods: Seventy-two SD rats were randomly divided into three groups (n=24): Sham group, ICH group and MCC950 group. ICH group and MCC950 group rats were injected with autogenous non-anticoagulant blood to establish ICH model, and then the rats in MCC950 group were intraperitoneally injected with MCC950 at the dose of 10 mg/kg(2 mg/ml) for 3 days after ICH model was established. Seventy-two hours after the establishment of the model, the forelimb placement test, the corner test and mNSS score were performed to observe the neurological function of the rats with ICH. The volume of hematoma was observed in fresh brain tissue sections. HE staining was used to observe the pathological changes of brain tissue. The dry-wet weight ratio was calculated to evaluate the changes of brain tissue edema. The degeneration of neurons was observed by FJC staining. The neuronal apoptosis was observed by TUNEL staining. The protein expression and activation levels of NLRP3, ASC, caspase-1, IL-1β, IL-18 and GSDMD were determined by Western blot. Results: Compared with sham group, the percentage of successful placement of left forelimb and left turn was decreased significantly (P＜0.01, P＜0.05), mNSS score was increased significantly (P＜0.01) in ICH group. Hematoma volume was increased significantly, the number of microglial cells around the hematoma was increased, the number of neurons was decreased, nerve cell swelled, some cells showed pyknotic necrosis, and the staining was deepened. The water content of the right base was increased significantly (P＜0.05). The number of FJC positive and TUNEL positive cells around the hematoma was increased significantly (P＜0.05). The levels of NLRP3, ASC, caspase-1, pro-caspase-1, caspase-1/pro-caspase-1 ratio, GSDMD-N, GSDMD, GSDMD-N/GSDMD ratio, IL-1β and IL-18 were increased significantly (P＜0.01, P＜ 0.05). Compared with ICH group, the percentage of successful placement of left forelimb and left turn was increased significantly in MCC950 group (P＜0.05), while the mNSS score and the volume of hematoma were decreased significantly (P＜0.01), the swelling degree of nerve cells around the hematoma was reduced significantly, and the number of pyrotic necrotic cells was decreased. The water content of the right base was decreased significantly (P＜0.05), and the number of FJC positive and TUNEL positive cells around the hematoma was decreased significantly (P＜0.05). The levels of NLRP3, ASC, caspase-1, pro-caspase-1, caspase-1/pro-caspase-1 ratio, GSDMD-N, GSDMD, GSDMD-N/GSDMD ratio, IL-1β and IL-18 were decreased significantly (P＜0.05). Conclusion: MCC950 can ameliorate nerve injury after ICH by inhibiting NLRP3 inflammasome mediated inflammation and pyroptosis.

Block nucleotide-binding oligomerization domain-like receptor protein 3 inflammasome to alleviate non-alcoholic steatohepatitis and liver fibrosis / 中华消化杂志

Objective:To explore the role of nucleotide-binding oligomerization domain-like receptor protein 3 (NLRP3) inflammasome in non-alcoholic steatohepatitis (NASH).Methods:The liver tissue samples of 24 patients admitted the Second Affiliated Hospital of Fujian Medical University were selected, including 12 NASH samples from liver biopsy and 12 normal liver tissues from the margin of hepatic hemangioma. The expression of NLRP3, apoptosis-associated speck-like protein (ASC), caspase-1, interleukin (IL)-1β and the content of triglyceride (TG) were detected. Wild-type and NLRP3 -/- C57BL/6 mice were fed with normal diet or methionine-choline deficient diet (MCD) for 8 weeks. The wild-type mice were divided into MCC950 NASH, 0.9% sodium chloride (NaCl) NASH, MCC950 and 0.9% NaCl group, 8 mice in each group, and were fed with MCD diet and treated with MCC950, fed with MCD diet and treated with 0.9% NaCl, fed with normal diet and treated with MCC950, and fed with normal diet and treated with 0.9% NaCl respectively for eight weeks. After eight weeks, the pathologic changes of liver tissues were observed with hematoxylin-eosin staining and immunohistochemistry. The levels of alanine aminotransferase (ALT), aspartate aminotransferase (AST), free fatty acid (FFA), IL-1β and TG in serum were determined by enzyme linked immunosorbent assay. The expression levels of NLRP3, ASC, caspase-1 and IL-1β in liver tissues were examined by Western blotting and real-time quantitative polymerase chain reaction. Primary Kupffer cells were isolated and cultured from the livers of wild-type and NLRP3 -/- mice and divided into control group and palmitic acid group. The expression levels of related proteins in the supernatant of cells culture were detected by Western blotting. Independent sample t test and one-way ANOVA were used for statistical analysis. Results:The expression levels of NLRP3, ASC, caspase-1, IL-1β and the content of TG of the liver tissues of the NASH patients were all higher than those of healthy control group (all P<0.05). The formation of steatohepatitis in hepatocyte of MCD-fed mice was more obvious than that of nomal diet-fed mice, with more hepatocyte ballooning and inflammatory cell infiltration. The expression of NLRP3, ASC, caspase-1, IL-1β, caspase-1 activity and the content of TG in liver tissue of NASH mice were all higher than those of normal diet-fed group (all P<0.05); and serum levels of ALT, AST, IL-1β, and the content of FAA were all higher than those of normal diet-fed group (all P<0.05). The serum levels of ALT, AST, IL-1β and IL-18 of NLRP3 -/- NASH mice were all lower than those of wild-type NASH mice (all P<0.05). The serum level of ALT, the expression of ASC, caspase-1 and IL-1β in liver tissues, and the degrees of liver fibrosis of wild-type MCC950 NASH group were all lower than those of 0.9% NaCl NASH group (all P<0.05). The expression of NLRP3, ASC, caspase-1, caspase-1 activity, and secretion of IL-1β and IL-18 in Kupffer cells from wild-type mouse treated with palmitic acid were all higher than those of the negative control group (all P<0.05). However, the changes of the above indicators in Kupffer cells from NLRP3 -/- mouse were not affected by palmitic acid treatment. Conclusion:NLRP3 blockade can significantly alleviate the liver injury and fibrosis in NASH mice and prevent the development of NASH.

Pediatric bacterial meningitis and meningococcal disease profile in a Brazilian General Hospital

Abstract Objective To evaluate the clinical and epidemiological profile of bacterial meningitis and meningococcal disease in pediatric patients admitted to a Brazilian Secondary Public Hospital. Methods A descriptive observational study was conducted. Microbiologically proven bacterial meningitis or meningococcal disease diagnosed from 2008 to 2018 were included. Results A total of 90 patients were diagnosed with proven bacterial meningitis. There were 64 confirmed cases of meningococcal disease. The prevalence was higher in boys (n=38), median age 30 months (1-185). The main clinical manifestations were: meningococcal meningitis (n=27), meningococcemia without meningitis (n=14), association of meningococcemia with meningitis (n=13), and fever without a known source in infants (n=7).Admissions to intensive care unit were necessary for 45 patients. Three deaths were notified. Serogroup C was the most prevalent (n=32) followed by serogroup B (n=12).Pneumococcal meningitis was identified in 21 cases; out of the total, 10 were younger than two years. The identified serotypes were: 18C, 6B, 15A, 28, 7F, 12F, 15C, 19A and 14. Pneumococcal conjugate 10-valent vaccine covered four of the nine identified serotypes.Haemophilus influenzae meningitis serotype IIa was identified in three patients, median age 4 months (4-7). All of them needed intensive care. No deaths were notified. Conclusion Morbidity and mortality rates from bacterial meningitis and meningococcal disease remain high, requiring hospitalization and leading to sequelae. Our study observed a reduced incidence of bacterial disease over the last decade, possibly reflecting the impact of vaccination.

Characterization Of Kapok Pericarpium Microcrystalline Cellulose Produced Of Enzymatic Hydrolysis Using Purified Cellulase From Termite (MACROTERMES Gilvus)

Objective: This study aimed to increase the yield of microcrystalline cellulose (MCC) from kapok pericarpium alpha-cellulose produced by enzymatic hydrolysis using purified cellulase from Termites (Macrotermes gilvus) and to compare the characteristics with the reference product. Methods: In this research, MCC was prepared from kapok pericarpium powder through the chemical isolation process of alpha-cellulose, followed by enzymatic hydrolysis with purified cellulase from Macrotermes gilvus. The yield was improved by using purified cellulase in optimized temperature, pH, and hydrolysis time. Identification was carried out by using ZnCl and infrared spectrophotometry, followed by characterization of MCC include particle size analysis (PSA) and diffracto­gram pattern (X-Ray Diffraction). The results were compared with Avicel PH 101 as the reference product. Results: Purified cellulase from Macrotermes gilvus showed high cellulose activity. Cellulose in the concentration of 11.743 U/ml formed 49 mm clear zone area with cellulolytic index 7.16 that similar to the formed clear zone area of Trichoderma reesei (50 mm), the optimum hydrolysis condition was achieved at 50 °C, pH 6.0, in 2 h, which produced 80% yield of MCC. Produced MCC was analyzed with ZnCl and FTIR spectrum resulting in positive results, similar to reference. The results of the organoleptic test, particle size analysis, and diffracto­gram pattern (X-Ray Diffraction) showed crystalline characteristics of MCC is similar to the reference (Avicel PH 101). Conclusion: Cellulase Macrotermes gilvus yielded 80% MCC and higher enzymatic activity than Trichoderma reesei. Based on the organoleptic test, particle size analysis, and diffracto­gram pattern observation, MCC from kapok pericarpium has shown similar characteristics to reference (Avicel pH 101) and might be potential to be further developed.

Protection of Mcc950 against H2O2-induced inflammatory injury in ARPE-19 cells / 国际眼科杂志(Guoji Yanke Zazhi)

@#AIM: To research the protection of Mcc950, the inhibitor of NLRP3, against the inflammatory injury to human retinal pigment epithelium cell line ARPE-19. <p>METHODS: Cultured cell line ARPE-19 was divided into control group, H₂O₂ treating group, Mcc950 treating group and Mcc950+H₂O₂ treating group. Different concentrations of H₂O₂ and Mcc950 were used to treat the cells. Cell activity was detected by using CKK8 and proper experimental concentration of H₂O₂ and Mcc950 were determined. After the treatment, the concentration of IL-1β were detected by using ELISA. The change of NLRP3 related proteins were detected by Western blot. And cell apoptosis was examined by TUNEL stain. <p>RESULTS: Cell ability was gradually decreased along with the increasing treating concentrations of H₂O₂. Cell ability showed statistical difference when the concentration of H₂O₂ arrived 400μmol/L. With the concentration of 0.1 and 1μmol/L, Mcc950 had no effect on cell ability. So we chose 400μmol/L H₂O₂ and 1μmol/L Mcc950 as the experimental concentrations. Compared with the normal control group, the cell viability in the H₂O₂ treating group was significantly reduced, the IL-1β in the supernatant was significantly increased, and the apoptosis rate was significantly increased, with statistically significant differences(<i>P</i><0.05). In Mcc950+H₂O₂ treating group, cell viability was significantly increased, the IL-1β in the supernatant and the apoptosis rate were significantly decreased(<i>P</i><0.05). By Western blot, after treated with 400μmol/L H₂O₂, the IL-1β, NLRP3, pro-caspase1 and caspase1 were obviously increased compared to control group. After treated with Mcc950, the NLRP3 and pro-caspase1 still were at high level, the expression of caspase1 was suppressed, which indicated that Mcc950 effectively inhibited the activation of NLRP3 inflammasome consequently disturbed the formation of caspase1.<p>CONCLUSION: Mcc950 can inhibits the function of NLRP3, leading to increasing of the cell ability and decreasing of the cell apoptosis.

Optimization of prescriptions for Yuanhu Zhitong Orally Disintegrating Tablets based on central composite design-response surface methodology / 中草药

Objective To optimize the best prescription of Yuanhu Zhitong Oral Disintegrating Tablets (YZODT). Methods Using the single factor test, the prescription of the tablets was optimized by central composite design-response surface methodology (CCD-RSM) with the tablet wetting time and the disintegration time limit as evaluation index, so as to determine the best preparation process. Results The dosages of the optimized prescription of MCC, L-HPC, and PVPP were 30%, 15%, and 5%, respectively. The average disintegration time of the optimized YZODT was 42.89 s, and the deviation from the predicted value was 3.27%. Conclusion The optimized YZODT has the advantages of fast disintegration, moderate hardness, convenient use, and simple process.

Protective effect of MCC950 against lung injury induced by mitochondrial damage-associated molecular patterns / 医学研究生学报

Objective There is still no specific immuno-therapy to acute respiratory distress syndrome induced by severe trau-ma.The article aimed to investigate the effect of MCC 950 on lung in-jury induced by mitochondrial damage-associated molecular patterns ( MTDs) and preliminarily evaluate its molecular mechanism . Methods 40 SD rats were randomly devided into control group , MTDs group, MCC950 group, MTDs+MCC950 group.The rats were were taken MCC950 (20mg/kg) by peritoneal injection pretreatment for 1 hour, followed by tail vein injection of MTDs (5%liver vol-ume) and were killed 12 hours later.ELISA were applied to detect tumor necrosis factor (TNF-α), interleukin-1β( IL-1β) and IL-18 in broncho-alveolar lavage fluid ( BALF) , and BCA method to assess the content of total protein .Lung tissues were weighed to calculate lung wet weight/body weight( LWW/BW) ratio, and stained by HE staining to observe the pathological changes through light micro -scope.Smith lung injury score was used to assess histological lung injury .Western blot was employed to evaluate the protein expression of Pro-Caspase-1 and Caspase-1. Results ①Compared with control group , TNF-α, IL-1βand IL-18 in BALF of MTDs group were significantly increased( all P<0.05), but not in MCC950 group(P>0.05), TNF-αin BALF of MTDs +MCC950 group were signifi-cantly increased( all P<0.05), IL-1βand IL-18 were not(all P>0.05).Compared with MTDs group, IL-1βand IL-18 in BALF of MTDs +MCC950 group were in serious decline (all P<0.05).Compared with control group, the LWW/BW ratio [(4.19±0.36)mg/g vs (6.32±0.54)mg/g, P<0.05] and the content of total protein [(0.12±0.03)g/L vs (0.79±0.07)g/L, P<0.05] were dramatically increased.Compared with MTDs group, the LWW/BW ratio [(4.35±0.29)mg/g, (4.47±0.0.46)mg/g, P<0.05] and the content of total protein [(0.12±0.06)g/L, (0.15±0.06)g/L, P<0.05] were in serious decline.Smith lung injury score revealed that compared with control group the score of MTDs group was elevated (1.00±0.00 vs 8.33±0.58, P<0.05), and the score of MTDs+MCC950 group was significantly decreased than MTDs group ( 8.33±0.58 vs 3.67±0.58, P<0.05) .Compared with control group , the protein expres-sion of Pro-caspase-1 and caspase-1 were markedly improved (all P<0.05).However, the expression of caspase-1 was significantly milder than that in MTDs group ( P<0.05), the protein expression of Pro-caspase-1 was comparable ( P>0.05). Conclusion MCC950 exerts protective effect against lung injury induced by MTDs probably via the inhibition of NLRP 3 inflammasome activation .

Maternal 3-methylcrotonyl-coenzyme A carboxylase deficiency with elevated 3-hydroxyisovalerylcarnitine in breast milk / 소아과

We report here a case of maternal 3-methylcrotonyl-coenzyme A carboxylase (3-MCC) deficiency in a Korean woman. Her 2 infants had elevated 3-hydroxyisovalerylcarnitine (C5-OH) on a neonatal screening test by liquid chromatography-tandem mass spectrometry (LC-MS/MS), but normal results were found on urine organic acid analysis. The patient was subjected to serial testing and we confirmed a maternal 3-MCC deficiency by blood spot and breast milk spot test by LC-MS/MS, serum amino acid analysis, urine organic acid and molecular genetic analysis that found c.838G>T (p.Asp280Tyr) homozygous mutation within exon 9 of the MCCB gene. Especially, we confirmed marked higher levels of C5-OH on breast milk spot by LC-MS/MS, in the case of maternal 3-MCC deficiency vs. controls.

TORC2 and eisosomes are spatially interdependent, requiring optimal level of phosphatidylinositol 4, 5-bisphosphate for their integrity.

The elucidation of the organization and maintenance of the plasma membrane has been sought due to its numerous roles in cellular function. In the budding yeast Saccharomyces cerevisiae, a novel paradigm has begun to emerge in the understanding of the distribution of plasma membrane microdomains and how they are regulated. We aimed to investigate the dynamic interdependence between the protein complexes eisosome and TORC2, representing microdomains MCC and MCT, respectively. In this study, we reveal that the eisosome organizer Pil1 colocalizes with the MCT marker Avo2. Furthermore, we provide evidence that the formation of MCT is dependent on both eisosome integrity and adequate levels of the plasma membrane phosphoinositide PI(4,5)P2. Taken together, our findings indicate that TORC2, eisosomes, and PI(4,5)P2 exist in an interconnected relationship, which supports the emerging model of the plasma membrane.

Design, Formulation and Tableting Properties of Aqueous Leaf Extract of Moringa oleifera.

Aim: The aim of this study is to formulate a standard dose of aqueous extract of Moringa oleifera leaves into tablets and to determine a suitable binder for the formulation. Methodology: Aqueous extract of Moringa oleifera leaves was extracted and formulated using different binders which included Maize Starch, Gelatin and Micro-crystalline Cellulose (MCC) to find out which one produce better tablets of aqueous extract of Moringa oleifera leaves. Formulations were characterized using various parameters such as physicochemical properties (bulk density, tapped density, moisture content, Hausner’s ratio, Carr’s index, ash value), strength (friability and crushing strength) and release properties (disintegration and dissolution times tests). The result showed that tablets formulated with Gelatin as a binder has lowest friability and disintegration time compared to those formulated with either MCC or maize starch. The crushing strengths were all within the acceptable limit (3 – 6 KgF) except maize starch which was higher. Conclusion: Moringa oleifera tablets were successfully formulated and based on experiments conducted, Gelatin is preferable in the formulation of Moringa oleifera tablets.

Formulation and Dissolution Study of Valsartan Immediate Release Tablets.

In the present study, design of oral immediate release tablets of Valsartan by direct compression technique was carried out. The main aim and objective of the work is to formulate immediate release tablets using different direct compression vehicles (DCV’S) in different ratios. The main motive is to compare the dissolution profile of these formulations and conclude the best formulation which release drug at a faster rate. To determine the best fit dissolution profile for the dosage forms. Valsartan tablets were formulated by using microcrystalline cellulose (diluents), potato starch, acacia (binder) and magnesium stearate (lubricant). The granules were compressed into tablets and were subjected to dissolution studies. The dissolution profile of the formulation F2 was found to have better dissolution rate compared to others. The In-vitro dissolution studies of all the formulations were conducted and the results were obtained, it was concluded that formulation F2 was the best with fast release of drug compared to others.

Medicine counseling services at Tertiary care Hospital in Nepal

Background and Objectives: Patient needs specific guidelines from their pharmacist in support of better compliance of their medicine used. Counseling of the patient and patient representative is important for improving the therapeutic out comes. Counseling patients can improve their understanding regarding medication, disease and life style modifications which in turn improves compliance. Material and Methods: Patients and/or patient party were counseled as per the Omnibus Budget Reconciliation Act-1990 guidelines. The data was collected as per OBRA-90 during the period of eighteen month and was analyzed using statistical software SPSS version 17. Results: Three hundred and fifty patients were counseled during the study period. Majority of the counseled patients were females [75.9%]. Mean counseling time taken by the pharmacist was 7.43 minute. Minimum time taken to counsel the patient was 6-10 minutes in 58.41% of the counseled, followed by less than 5 minutes in 19.68% and 11-15 minutes in 8.89%. About 10.47% were counseled for more than 15 minutes by the pharmacist. Greater numbers of the patients referred to the Medicine Counseling Center (MCC) were from Obstetrics and Gynecology departments and most of them were directed by doctors [50.47%]. Conclusion: This study highlights that role of doctor is important to encourage patient to attend counseling services. Counseling is the integral part that not only help patient to understand the use of their medicine but also to improve their therapeutic out comes. The effect of counseling on compliance should be studied in future.

Morphologic studies of the retina in a new diabetic model; SHR/N:Mcc-cp rat

The pathogenesis of diabetic retinopathy has not been fully explained. The earliest histological lesion is the loss of intramural pericytes and thickening of the basement membrane. Increased activity of the polyol pathway is a probable mechanism for these two abnormalities. Investigations have suffered from the lack of an exact animal model simulating the human condition. Examination of the retina in the spontaneously diabetic SHR/N:Mcc-cp rat demonstrated degeneration and loss of intramural pericytes, a progressive increase in basement membrane thickness, and microinfarctions with an area of non-perfusion. Therefore, this model may be used to clarify the biochemical mechanisms linking the metabolic abnormalities of diabetes and retinopathy.

The role of G protein and protein kinase C mechanical signalling transduction in mandibular condylar chondrocytes / 实用口腔医学杂志

Objective: To investigate the expression and distribution of G protein and protein kinase C (PKC) under the mechanical pressure in rabbit mandibular condylar chondrocytes (MCCs) and to study the role of G protein in PKC signalling pathway. Methods:MCCs from two-week-old New Zealand rabbits were cultured. After treatment under continuous pressure of 90 kPa for 60 min or 360 min by hydraulic pressure controlled cellular strain unit, the expression of G?q/11 protein was examined by Western Blot. The expression and distribution of PKC was observed by immunocytochemical staining. Results:Gaq/11 protein in MCCs treated by 90 kPa for 60 min and 360 min was increased by 163.7% and 65.8% respectively(P0.05). PKC in control cells distributed uniformly in the cytoplasm. After been pressed under 90 kPa for 60 min,PKC translocated to the membrane and, partly,into nuclei. When the pressure prolonged to 360 min, PKC distributed uniformly again in cytoplasm. By treatment of G protein inhibitor, the translocation of PKC under 90 kPa of 60 min was not observed. Conclusion:Feasible pressure may promote G protein expression and activate PKC. The activation of PKC signalling pathway is mediated by G protein.