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Objective To observe the impacts of Xinnaoning capsules on the aortic intimal structure,serum levels of diponectin (APN) and calcium sensing receptor (CaSR) expression in rats with myocardial infarction,and explore the endothelial protection mechanisms of Xinnaoning.Methods 15 male Sprague Dawley (SD) rats in sham operation group were randomly selected from 60 rats,the rest 45 rats were fed with high fat diet for 6 weeks and received coronary artery ligation operation.The successful modeling rats were randomly divided into model group,western medicine group and traditional Chinese medicine (TCM) group,and fed with high fat diet for 8 weeks.The sham operation group fed with normal diet.The western medicine group and TCM group received atorvastatin and Xinnaoning capsules,respectively;the sham operation group and model group received same amount of distilled water.After treatment of 4 weeks,the aortic intimal structure was observed by hematoxylin-eosin (HE);the serum levels of triacylglycerol (TG),total cholesterol (TC),low density lipoprotein (LDL) and high density lipoprotein (HDL) were measured by microplate test;serum levels of APN and CaSR expression were determined by enzyme linked immunosorbent assay (ELISA) and Western blot,respectively.Results Compared with sham operation group,aortic intimal structure derangement and plaque formation in intima in model group,and serum levels of TG,TC,LDL and CaSR expression were increased;HDL and APN were decreased (P ＜ 0.05).Compared with model group,the endarterium was more smooth in the western medicine group and TCM group,serum levels of TG,TC,LDL and CaSR expression were decreased;HDL and APN were increased (P ＜0.05).And there were no significant differences between western medicine group and TCM group (P ＞0.05).Conclusions Xinnaoning capsules are effective for myocardial infarction.
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Objective@#To observe the impacts of Xinnaoning capsules on the aortic intimal structure, serum levels of diponectin (APN) and calcium sensing receptor (CaSR) expression in rats with myocardial infarction, and explore the endothelial protection mechanisms of Xinnaoning.@*Methods@#15 male Sprague Dawley (SD) rats in sham operation group were randomly selected from 60 rats, the rest 45 rats were fed with high fat diet for 6 weeks and received coronary artery ligation operation. The successful modeling rats were randomly divided into model group, western medicine group and traditional Chinese medicine(TCM) group, and fed with high fat diet for 8 weeks. The sham operation group fed with normal diet. The western medicine group and TCM group received atorvastatin and Xinnaoning capsules, respectively; the sham operation group and model group received same amount of distilled water. After treatment of 4 weeks, the aortic intimal structure was observed by hematoxylin-eosin (HE); the serum levels of triacylglycerol (TG), total cholesterol (TC), low density lipoprotein (LDL) and high density lipoprotein (HDL) were measured by microplate test; serum levels of APN and CaSR expression were determined by enzyme linked immunosorbent assay (ELISA) and Western blot, respectively.@*Results@#Compared with sham operation group, aortic intimal structure derangement and plaque formation in intima in model group, and serum levels of TG, TC, LDL and CaSR expression were increased; HDL and APN were decreased (P<0.05). Compared with model group, the endarterium was more smooth in the western medicine group and TCM group, serum levels of TG, TC, LDL and CaSR expression were decreased; HDL and APN were increased (P<0.05). And there were no significant differences between western medicine group and TCM group (P>0.05).@*Conclusions@#Xinnaoning capsules are effective for myocardial infarction.
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Objective To study the changes of intracellular calcium ion concentration in pulmonary artery smooth muscle cells (PASMCs) of hypoxic-induced persistent pulmonary hypertension (PPH) induced by calcium-sensitive receptor (CaSR) in a newborn mouse model.Method Ninety-six newbom C57BL/6 mice were randomly divided into control group,PPH group,PPH + agonist group and PPH + inhibitor group,with 24 mice in each group.The PPH model was induced by 12％ oxygen for 14 days.In the beginning,intraperitoneal injection of CaSR agonist (GdCl3) and CaSR inhibitor (NPS2390) were performed to mice in PPH + agonist group and PPH + inhibitor group respectively daily.After 14 days of modeling,pulmonary artery smooth muscle cells (PASMCs) of all four groups were cultured in vitro.Changes of Ca2+ fluorescence intensity in PASMCs of the four groups were detected by laser confocal microscope continuously.Result The ratio of pulmonary small vascular wall thickness to the vascular diameter and right ventricle/left ventricular thickness in PPH group were greater than those in the control group [(21.1％ ±1.8％) vs.(27.0％ ±0.9％),(0.62 ±0.22) vs.(0.83±0.45)],the differences were statistically significant (P ＜ 0.05),which imply that PPH mouse model was constructed successfully.The average Ca2+ fluorescence intensity in PASMCs of control group,PPH group,PPH + agonist group and PPH+ antagonist group were 122.5 ± 3.0,2 058.8 ±46.3,2 286.6 ±51.4 and 1 134.8 ± 8.5,respectively.The average Ca2+ fluorescence intensity in PASMCs of the PPH group,PPH + agonist group and PPH + antagonist group was higher than that of the control group respectively,the average Ca2+ fluorescence intensity in PASMCs of PPH group was higher than that of PPH + antagonist group,the differences were statistically significant (P ＜ 0.05).Whereas the difference of average Ca2 + fluorescence intensity in PASMCs of PPH group and PPH + agonist group was of no statistical significance (P ＞ 0.05).Conclusion CaSR may be involved in the occurrence and development of hypoxic-induced PPH in neonatal mice by affecting the intracellular Ca2+ concentration in pulmonary artery smooth muscle cells.
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Objective@#To investigate the interaction of Ca2+ protein TRPC1 and STIM1 in extracellular Ca2+ -sensing receptor (CaR)-induced extracellular Ca2+ influx and the production of nitric oxide (NO).@*Methods@#Human umbilical vein endothelial cells (HUVECs) were cultured and incubated with CaR agonist spermine (activating store-operates cation channels (SOC) and receptor-operated channels (ROC)), CaR negative allosteric modulator Calhex231 (blocking SOC, activating ROC) and ROC analogue TPA (activating ROC, blocking SOC), protein kinase C (PKC) inhibitor Ro31-8220, PKCs and PKCμ inhibitor Go6967(activate SOC, blocking ROC), respectively. The interaction of TRPC1 and STIM1 was determined using the immunofluorescence methods. The interaction between TRPC1 and STIM1 were examined by Co-immuno precipitation. The HUVECs were divided into: TRPC1 and STIM1 short hairpin RNA group (shTRPC1+ shSTIM1 group), vehicle-TRPC1+ vehicle-STIM1 group and control group. The cells were incubated with four different treatments under the action of above mentioned interventions, intracellular Ca2+ concentration ([Ca2+ ]i) was detected using the fluorescence Ca2+ indicator Fura-2/AM, the production of NO was determined by DAF-FM.@*Results@#(1) The expression of TRPC1 and STIM1 proteins levels in HUVECs: Under the confocal microscope, TRPC1 and STIM1 protein expression showed masculine gender, both located in cytoplasm in the normal control group. Post incubation with Calhex231+ TPA, Ro31-8220 and Go6967, TRPC1 and STIM1 positioned in cytoplasm was significantly reduced, and the combined TRPC1 and STIM1 was also significantly reduced. (2) The interaction of TRPC1 and STIM1 in HUVECs: The relative ratios of Calhex231+ TPA+ Spermine+ Ca2+ group, Ro31-8220+ Spermine+ Ca2+ group and Go6976+ Spermine+ Ca2+ group STIM1/TRPC1 and TRPC1/STIM1 were as follows: (25.98±2.17)% and (44.10±4.01)%, (20.85±1.01)% and (46.31±3.47)%, (23.88±2.05)% and (39.65±2.91)%, which were significantly lower than those in the control group (100.00±4.66)% and (100.00±6.40)% and in the Spermine+ Ca2+ group (106.04±2.45)% and (107.78±2.66)% (all P<0.05). (3) The influence of joint TRPC1 and STIM1 transfection to four different drugs treated HUVECs on [Ca2+ ]i and NO generation: The changes of two excitation fluorescence intensity ratio and NO net fluorescence intensity values were consistent, [Ca2+ ]i and NO net fluorescence intensity values were significantly lower in the experimental group than the control group and the vehicle group (all P<0.05), while which were similar between the vehicle group and control group (all P>0.05).@*Conclusions@#Our results indicate that TRPC1 and STIM1 jointly regulate CaR-mediated Ca2+ influx and nitric oxide generation in HUVECs in the form of binary complex.
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Objective To evaluate the efficacy and safety of cinacalcet on secondary hyperparathyroidism (SHPT) in patients with end-stage renal disease (ESRD). Methods Patients with ESRD and SHPT for the treatment with calcimimetic agents were included in this study. MEDLINE (1996.1-2014.9), OVID (1963.1-2014.9), Chinese Wanfang database (1996.1-2014.9), CNKI (1996.1-2014.9) and the clinical control test database of Cochrane Library were searched . Related literature, including published or unpublished papers, and meeting procedding were hand-searched. Quality assessment and data extraction were conducted by two independent investigators. Meta-analysis was conducted by RevMan 5.2. Results Nineteen randomized controlled trials involving 7 702 patients were included. The meta-analysis showed that compared with conventional therapy,cinacalcet can significantly decrease serum parathyroid hormone in dialysis patients [WMD=-301.54 μg/L, 95%CI:(-344.38)-(-258.7)μg/L, P0.05). Cinacalcet increased nausea (RR =2.05, 95%CI :1.53-2.75, P0.05). Conclusion Results confirm that cinacalcet suppresses parathyroid hormone and decreases calcium and phosphorus in secondary hyperparathyroidism patients receiving dialysis. Cinacalcet increases risks of nausea, vomiting, diarrhea and hypocalcaemia,without increasing mortality.
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Objective To evaluate the effect of sevoflurane on the expression of calcium-sensing receptor (CaSR) in the myocardium of rats with high-level spinal cord injury (SCI).Methods Thirty healthy male Wistar rats, weighing 250-300 g, were randomly divided into 3 groups using a random number table: sham operation group (group S, n = 6) , SCI group (n =12) and sevoflurane group (group Sev).SCI was induced in anesthetized rats by dropping a l0-g weight onto C7 spinal cord from 5.0 cm height falling freely inside a vertical hollow glass tube.Group SCI inhaled 2 L/min pure oxygen for 30 min, and group Sev inhaled 2％ sevoflurane for 30 min starting from 30 min after SCI.At 12 and 24 h after SCI (T1,2) , 6 rats were selected randomly, and blood samples from the abdominal aorta were drawn for determination of serum cardiac troponin I (cTnI) concentrations.The rats were then sacrificed, and myocardial specimens were obtained for determination of CaSR protein and mRNA expression (using fluorescent quantitative real-time reverse transcriptase-polymerase chain reaction or Western blot) and for examination of myocardial ultrastructure (with transmission electron microscope).Results Compared with group S, the serum cTnI concentrations and CaSR protein and mRNA expression were significantly increased at T1,2 in SCI and Sev groups.Compared with group SCI, the serum cTnI concentrations and CaSR protein and mRNA expression were significantly decreased at T1,2 in Sev group.The damage to myocardial cells was significantly reduced in group SCI compared with group Sev.Conclusion Sevoflurane reduces myocardial damage through inhibiting CaSR expression in the myocardium of rats with high-level SCI.
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Objective To investigate the effect of creatine phosphate sodium on myocardial protection and calcium-sensitive receptor (CaSR) expression following high-level spinal cord injury.Methods Thirty healthy male SD rats weighing 250-300 g were assigned to sham operation,12-hour injury,24-hour injury,12-hour injury followed by a single intraperitoneal injection of creatine phosphate sodium,and 24-hour injury followed by a single intraperitoneal injection of creatine phosphate sodium according to the random number table,with 6 rats in each group.High-level spinal cord injury was induced at C7 segment by dropping a 10 g weight falling freely along the hollow glass tube from a 5 cm height.Level of blood troponin Ⅰ (cTnⅠ) was measured.Myocardial tissues were collected to study ultrastructure of myocardial cells under transmission electron microscope and CaSR expression using fluorescence quantitative PCR and Western blotting.Results cTnⅠ level was (0.031 ±0.002) U/L and (0.026 ± 0.001) U/L in 12-and 24-hour injury groups,but it was reduced to (0.023 ± 0.002) U/L and (0.018 ± 0.006) U/L at the same time point in treatment groups (P ＜ 0.05).Whereas either in injnry or treatment groups,cTnⅠ level was higher than (0.004 ± 0.002) U/L in sham operation group (P ＜ 0.05).CaSR mRNA level was (0.991 ±0.146) × 10-3 and (1.245 ±0.204) × 10-3 in 12-and 24-hour injury gronp and decreased to (0.880 ± 0.096) × 10-3 and (0.782 ± 0.138) × 10 3 at the same time point in treatment groups (P ＜ 0.05),but all were higher than (0.437 ± 0.065) × 10-3 in sham operation group (P ＜ 0.05).CaSR protein expressed in 12-and 24-hour injury group was (0.627 ±0.066) × 10 3 and (0.809 ±0.154) ×10 3 and lowered to (0.505 ±0.176) × 10-3 and (0.524 ±0.138) × 10-3 at the same time point in treatment groups,but all were higher than (0.331 ± 0.102) × 10-3 in sham operation group (P ＜ 0.05).Transmission electron microscopy demonstrated normal myocardial ultrastructure in sham operation group but impairment in injury groups,but the impairment was significantly improved in treatment groups.Conclusion Creatine phosphate sodium can decrease cTnⅠ level,attenuate the damage to myocardial ultrastructure and down-regulate CaSR after high-level spinal cord injury.
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Objective To investigate the expressions of calcium sensitive receptor (CaSR) and tight junction protein (Claudin)-14 in renal calcium oxalate stone rat model. Methods Thirty male SD rats were randomly divided into control group (n=15) and model group (n=15). The rat model of renal calcium oxalate stone was established by gavaging 1%glycol (2 mL/d) and 2% ammonium chloride. The expression of CaSR protein was detected using immunohistochemical assay. RT-PCR was used to detect the Claudin-14 mRNA expression. The expression levels of CaSR and Claudin-14 protein were de-tected by Western blot assay respectively. The full automatic biochemical analyzer was used to detect rat renal function and changes of blood and urine biochemical indices. Results A large stone crystallization was observed under light microscope in model group. The serum levels of Cr, BUN, 24-h urine calcium and urine volume were significantly higher in model group than those of control group (P<0.01). There were no significant differences in serum calcium level and urinary pH value be-tween two groups. The expression levels of Claudin-14 mRNA and CaSR protein were significantly higher in model group than those of control group (P<0.01). The Claudin-14 protein expression was specifically higher in renal tissues of model group. There was no Claudin-14 protein expression in control group. There was a positive correlation between CaSR and Claudin-14 protein expression in renal tissues of model group. Also, CaSR and Claudin-14 protein expressions were posi-tively correlated with the 24-h urine volume. Conclusion The increased expressions of CaSR and Claudin-14 involved in the formation of kidney stone by increasing the urinary calcium excretion.
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ObjectiveTo explore the relationship among 25-hydroxyvitamin D,serum calcium,calcium-sensing receptor,and breast cancer. Methods The expressions of calcium-sensing receptor (CaSR) in primary breast cancer,breast benign tumors,and normal breast tissue beside tumors were determined by immunohistochemistry S-P method as well as the concentration of serum 25 (OH) D and serum calcium in breast cancer and breast benign tumors by Enzyme-linked immunosorbent assay (ELISA),Tribromoarsenazo Ⅲ method.ResultsSerum 25 (OH) D level of breast cancer was significantly lower than the breast benign tumors [ (34.13 ± 14.14) nmol/L vs (50.29 ± 25.65 ) nmol/L,t =2.870,P =0.001 ].Serum level of 25 ( OH ) D in lymph node metastasis positive patient was lower than that in negative group [ (30.8 ± 9.71 ) nmol/L vs (43.7 ± 23.59) nmol/L,t =2.467,P =0.021 ].The positive expression of CaSR in breast cancer(88.9％ )was higher than breast benign tumors(60％,x2 =6.717,P ＜ 0.01 ) and normal breast tissue beside tumors (60％,x2 =5.628,P ＜ 0.05 ).ConclusionsConcentration of serum 25 (OH)D and expression of calcium-sensing receptor in the tissues may be associated with occurrence,development and prognosis of breast cancer.
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Objective To explore the roles and possible mechanism of calcium-sensing receptor(CaSR) in cell cardiac hypertrophy model using angiotensin Ⅱ (Ang Ⅱ ).Methods The cultured neonatal rat ventricular myocytes were treated with Ang Ⅱ as cell cardiac hypertrophy model.Hypertrophic neonatal rat cardiomyocytes were treated with GdCl3(a specific agonist of CaSR) and/or with Ro318220(a specific inhibitor of PKC pathway).To evaluate the status of cardiac hypertrophy,cell diameter was observed by HE dyeing,and protein content was determined through coomassie brilliant blue protein kit.The intracellular calcium concentration( [ Ca2+]i) was determined by laser scanning confocal microscope.The protein expression of CaSR and PKC pathway were analyzed using Western blotting.Results ①Compared to the control group(0.1263 ± 0.0443),the protein expression of CaSR was increased in Ang Ⅱ group and in GdCl3 group(0.1963 ± 0.0375,0.2778 ± 0.0564,all P＜ 0.05).Moreover,compared with Ang Ⅱ alone,the increase was significant in GdCl3 group(P ＜ 0.05).②Compared to control group(222.70 ± 22.09),AngⅡ group(392.16 ± 36.85) remarkably increased [Ca2+]i(P＜ 0.05),and this increase of [Ca2+]i was further enhanced in GdCl3 group (502.60 ± 44.21) versus Ang Ⅱ group (P ＜ 0.05).③Compared to control group,Ang Ⅱ could induce cardiomyocyte hypertrophy,and GdCl3 enhanced the effect.Moreover,this enhancement was attenuated by Ro318220.④Compared to control group(0.27 ± 0.07,0.69 ± 0.06,0.87 ± 0.04),the protein expression of PKCα,PKCε and PKCδ was increased in Ang Ⅱ group(0.60 ± 0.16,1.02 ± 0.13,1.20 ± 0.18,all P＜ 0.05) and the protein expression of PKCα,PKCε was increased in GdCl3 group(0.82 ± 0.16,1.34 ± 0.12,all P ＜ 0.05).Moreover,compared with Ang Ⅱ group,the protein expression of PKCα,PKCε was obviously increased in GdCl3 group (all P ＜ 0.05);compared with GdCl3 group,the protein expression of PKCα,PKCε(0.41 ± 0.10,0.85 ± 0.14) was obviously decreased in Ro318220 group(all P ＜ 0.05).Conclusions CaSR is involved in cardiac hypertrophy induced by Ang Ⅱ through PKC pathway in cultured neonatal rat cardiomyocytes.
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ObjectiveTo investigate the role of myocardial calcium-sensing receptor (CaSR) in a rat model of high-level spinal cord injury (SCI).MethodsEighteen healthy male SD rats weighing 250-300 g were randomly divided into 2 groups:sham operation group(group S,n ＝6) and SCI group(n ＝ 12).SCI model was induced by dropping a 10 g weight onto spinal cord (C7) in freely vertical falling along the hollow glass tube from 5 cm height.The blood samples were taken 12 and 24 h after SCI in group SCI and 12 h after SCI in group S,and serum activity of creatine kinase(CK) and MB isoenzyme of creatine kinsse(CK-MB) were measured.Then myocardium specimens were obtained for uhrastructure examination and determination of CaSR mRNA and protien expression by fluorescence quantitative RCR and Western blot.Results Serum activities of CK and CK-MB and CaSR mRNA and protein expression were higher in group SCI than in group S.Serum activity of CK and CaSR mRNA expression were higher,and serum activity of CK-MB was lower at 24 h after SCI than that at 12 h after SCI.There was no significantly difference in CaSR protein expression between the two time points in group SCI.The ultrastructure examination showed that myocardial injury was found in group SCI.ConclusionThe expression of CaSR is up-regulated after SCI in rats,which might be the mechanism of myocardial injury after SCI.
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ObjectiveStudy the relationship among CaSR expression, tubulointerstitial damage,metabolic disturbance of calcium and phosphorus and microvascular density around the tubulointerstitium in children with steroid-resistant nephrotic syndrome.Methods36 cases of children with primary nephrotic syndrome were divided into hormone-sensitive group and steroid-resistant group.Semi-quantitative scores for tubulointerstitial pathological evaluation of the extent of damage, automatic biochemical analyzer for the determination of serum calcium (Ca), phosphorus (P) concentration of renal tubular epithelial CaSR expression and microvessel microvascular density around the tubulointerstitium were determined by immunohistochemical assay.ResultsMore severe the tubulointerstitial damage, lower level of serum Ca and higher level of serum P were observed [(2.26 ± 0.15) mmol/L]in children of the steroid-resistant group and the steroid-sensitive group [(1.90 + 0.12) mmol/L, P ＜ 0.05].CaSR expression (4.63 + 0.78) of renal tubular epithelial cells in the steroid- sensitive group was significantly lower than that in the steroid-resistant group (6.56 + 1.22, P ＜ 0.05), but microvascular density was significantly higher in the steroid- sensitive group(2.98 +0.35 vs 2.02 +0.24, P ＜0.05).When the tubulointerstitial damage was mild, CaSR expression (4.15 +0.58) in renal tubular epithelial cells in the steroid- sensitive group (4.26 ±0.61) was lower than the steroid-resistant group(3.12 ± 0.33; 3.01 ± 0.21), and microvascular density was higher,but the difference was not significant(P ＞0.05).In the moderate tubulointerstitial damage, CaSR expression in renal tubular epithelial cells in the steroid- sensitive group (5.35 ± 0.64) was significantly lower than the resistant group (7.37 +0.81, P ＜0.01), and microvascular density was significantly higher than the resistant group (2.81 ±0.16, 2.02 ±0.14, P ＜0.05).Compared by mild and moderate tubulointerstitial damage in children with the steroid-resistant, CaSR expression (11.46 ± 1.38) in children with severe tubulointerstitial damage was significantly increased, and microvascular density (1.15 ± 0.11) was significantly decreased (all P ＜ 0.01).ConclusionsCaSR expression was increased and microvascular density around the tubulointerstitium was decreased in children with steroid-resistant nephrotic syndrome.Dut to steroid resistance, the cytotoxic of steroid damaged the renal tubular epithelial cells, the metabolic disturbance of calcium and phosphorus and the damage of blood vessel endothelium finally resulted in severe tubulointerstitial damage.
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Hypoparathyroidism is an abnormality of calcium metabolism characterized by low serum levels of parathyroid hormone in spite of hypocalcemia. The causes of hypoparathyroidism are numerous. Activating mutations in the calcium-sensing receptor (CaSR) gene are well-known causes of familial isolated hypoparathyroidism, also known as autosomal dominant hypocalcemia (ADH). Here we describe members of a Korean family with a heterozygous Pro221Leu mutation causing ADH. This case is the first report in Korea.
Subject(s)
Female , Humans , Young Adult , Bone Density Conservation Agents/therapeutic use , Calcium Carbonate/therapeutic use , Heterozygote , Hydroxycholecalciferols/therapeutic use , Hypocalcemia/diagnosis , Mutation , Parathyroid Hormone/analysis , Pedigree , Receptors, Calcium-Sensing/genetics , Republic of Korea , Sequence Analysis, DNAABSTRACT
The extracellular calcium sensing receptor (CaSR) belongs to the type III family of G-protein-coupled receptors, a family that comprises the metabotropic glutamate receptor and the putative vomeronasal organ receptors. The CaSR plays an important role for calcium homeostasis in parathyroid cells, kidney cells and other cells to directly 'sense' changes in the extracellular calcium ion concentration ((Ca2+)o). The mesangial cells are known to be involved in many pathologic sequences through the mediation of altered glomerular hemodynamics, cell proliferation, and matrix production. In this study, we examined the expression of the CaSR in the mouse mesangial cell lines (MMC, ATCC number CRL-1927). Reverse transcription- polymerase chain reaction (RT-PCR) was perform with CaSR-specific primers, and this was followed by nucleotide sequencing of the amplified product; this process identified the CaSR transcript in the MMCs. Moreover, CaSR protein was present in the MMCs as assessed by Western blot and immunocytochemical analysis using a polyclonal antibody specific for the CaSR. Functionally, (Ca2+)o induced the increment of the intracellular calcium concentration ((Ca2+)i) in a dose-dependent manner. This (Ca2+)i increment by (Ca2+)o was attenuated by the pretreatment with a phospholipase C inhibitor (U73122) and also by a pretreatment with a CaSR antagonist (NPS 2390). The similar results were also obtained in IP3 accumulation by (Ca2+)o. To investigate the physiological effect of the CaSR, the effect of the (Ca2+)o on cell proliferation was studied. The increased (Ca2+)o (up to 10 mM) produced a significant increase in the cell numbers. This mitogenic effect of (Ca2+)o was inhibited by the co-treatment with a CaSR antagonist. From these results, the (Ca2+)o-induced (Ca2+)i elevation in the MMC is coupled with the extracellular calcium sensing receptor. Furthermore, (Ca2+)o produces a mitogenic effect in MMCs.
Subject(s)
Animals , Mice , Calcium/metabolism , Cell Line , Cell Proliferation , Inositol 1,4,5-Trisphosphate/metabolism , Mesangial Cells/cytology , RNA, Messenger/genetics , Receptors, Calcium-Sensing/geneticsABSTRACT
AIM:To observe the expression of calcium-sensing receptor(CaSR) of rat cardiomyocytes in anoxia-reoxygenation(A/R) injury and CaSR-induced changes of intracellular calcium;involvement of CaSR in apoptosis and relevant signaling transduction pathway.METHODS:The A/R injury was remodeled in vitro;CaSR,caspase 3 and caspase 9 were deteced by Western blotting.LSCM was used to observe changes of intracellular calcium during reperfusion with or without CaSR agonist.Morphological changes in different groups were observed by light microscopes.Apoptotic cells were measured by TUNEL assay.RESULTS:By LSCM,it was found that the intracellular calcium was significantly increased during reperfusion both in A/R and activator group.Severe injury was found by HE staining in the above two groups,the number of apoptotic cells was significantly increased according to TUNEL assay.The expression of CaSR,caspase 3 and caspase 9 was significantly increased in A/R group and activator group compared with control.CONCLUSION:CaSR is involved in intracellular calcium overload in A/R cardiomyocyte,which can accelerate apoptosis during A/R.
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AIM: To investigate the changes of expression of calcium-sensing receptor(CaSR) in the rat cardiac tissue at different age and its relation with anoxia-reperfusion(A/R) injury.METHODS: RT-PCR was used to detect the mRNA expression of CaSR.The A/R injury was remodeled in vitro,and the ultrastructure of cardiac tissue was observed under transmission electron microscope.RESULTS: The expression of CaSR mRNA in the rat cardiac tissue increased gradually after birth,and reached to its maximum in the 1st month.In the 2nd to 3rd month,the expression were almost equal to that at birth and then increased again to a higher level.The expression level of CaSR mRNA increased more significantly than those in control groups after 40 min of anoxia and reperfusion of 1 h and 2 h, and decreased after 3 h and 4 h.Moreover,the longer the reperfusion time lasted,the more serious the changes of ultrastructure were observed.CONCLUSION: Our results demonstrate that the CaSR is expressed in the rat cardiac tissue.The mRNA expression of CaSR changes with age and is involved in the anoxia-reperfusion injury.
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AIM: To investigate the expression of calcium sensing receptor(CaSR) during myocardial injury induced by ischemia/reperfusion and disclose the relationship between CaSR and myocardial ischemia/reperfusion. METHODS: The experimental model was established by the 30 min ligating and 1 h, 2 h, 4 h, 6 h reperfusing the left descending coronary artery (LAD) in rats. Wistar rats were randomly divided into 5 groups: sham group, ischemia/reperfusion 1 h, 2 h, 4 h, 6 h groups (I/R 1 h, 2 h, 4 h, 6 h group). CaSR mRNA expression was detected by RT-PCR. Left ventricular function was recorded. The levels of plasma lactate dehydrogenase (LDH), alondialdehyde (MDA) and superoxide dismutase (SOD) were measured. The change of ultrastructure in the ischemia/reperfusion myocardium of rats was observed by electron microscopy. RESULTS: LVSP,?dp/dtmax and SOD activity decreased gradually with the reperfusion time prolonged. LDH and MDA peaked at 2 h. The ultramicro-structural injury at the 1 h and 2 h was more serious than that at 4 h and 6 h. The expression of CaSR increased significantly after reperfusion of 1 h and 2 h, and decreased after 4 h and 6 h. CONCLUSION: The increased expression of CaSR mRNA and serious injure of myocardium were observed. CaSR may be associated with the myocardial ischemia/reperfusion injury.