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Heart and Vessels 04/2013; · 2.05 Impact Factor
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ABSTRACT: Abstract Objective. This study investigated the effects of short-term intermittent hypoxia (IH) preconditioning on cardiac structure and function in rats and the influence of ischemia reperfusion (I/R) injury. Special attention was then paid to the involvement of hypoxia-inducible factor-1α (HIF-1α) and vascular endothelial growth factor (VEGF). Methods. Wistar rats were given IH treatment for 1, 7, 14, or 28 days. Some of them were thereafter subject to myocardial infarction surgery. Right ventricle systolic pressure (RVSP), myocardial capillary density (CD), and mRNA/protein expression of HIF-1α, VEGF, and Bcl-2 in rat myocardial tissue were determined. Apoptotic cell number was determined by TUNEL staining, and concentrations of malondialdehyde (MDA) and superoxide dismutase (SOD) were measured. Results. IH treatment for 1, 7, 14, and 28 days reduced the myocardial infarction size, whereas IH for 28 days increased the RVSP, ratio of right to left ventricle weight (RV/LV+S), and CD. IH up-regulated the mRNA and protein levels of HIF-1α, VEGF, and Bcl-2 both under normal and I/R conditions. The induced expression of HIF-1α and VEGF by IH reached a peak after 7 days of treatment. Moreover, IH for 28 days induced cardiomyocyte apoptosis, whereas prior treatment with IH for 1, 7, 14, and 28 days all markedly attenuated the apoptosis effected by the subsequent I/R injury. IH also decreased the concentrations of MDA but increased those of SOD in myocardial tissue of both in normal rats and following I/R. Conclusions. The present study demonstrates that short-term IH protects the heart from I/R injury through inhibiting apoptosis and oxidative stress. The up-regulation of HIF-1α and VEGF by short-term IH may participate in the cardioprotective effect of IH.
Upsala journal of medical sciences 02/2013; · 0.73 Impact Factor
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ABSTRACT: AIM: The aim of this study was to explore meprinα-mediated transactivation of the epidermal growth factor receptor (EGFR) and reactive oxygen species (ROS) production in macrophages.Methods and ResultsAccelerated atherosclerotic lesions were established by administration of a high-fat diet in apolipoprotein E-deficient (apoE(-/-)) mice. Lentiviral overexpression of meprinα in the thoracic aortic artery during plaque formation enhanced intra-plaque macrophage induction of ROS as well as formation of atherosclerotic plaques, whereas AG1478 (specific inhibitor of the EGFR) treatment exerted the opposite effect. A meprinα inhibitor abrogated EGFR activation in mice. In cultured J774a.1 macrophages, oxidized low-density lipoprotein (OxLDL) increased ROS formation and EGFR activation through a ligand (heparin-binding epidermal growth factor-like growth factor (HB-EGF))-dependent pathway. However, a meprinα inhibitor or specific siRNA inhibited ROS production and EGFR activation. Recombinant mouse meprinα enhanced OxLDL-stimulated production of ROS and induced HB-EGF. Inhibition of p38 mitogen-activated protein kinase by SB203580 decreased OxLDL-stimulated production of ROS. Conversely, inhibition of meprinα or PI3 K-Rac1 inhibitors also decreased p38 activity in OxLDL-stimulated macrophages. In addition, inhibition of meprinα reversed OxLDL-stimulated activation of PI3 K. CONCLUSION: Meprinα promotes OxLDL-induced plaque formation and ROS release by transactivation of the EGFR, followed by activation of the PI3 K/Rac1/p38 pathway.
Cardiovascular research 12/2012; · 5.80 Impact Factor
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ABSTRACT: To enhance the safety of transendocardial delivery and the efficacy of intramyocardial angiogenic gene expression, a visible, less invasive, targeted, high-efficiency gene delivery strategy was tested. Progress toward clinical approval of systemic administration of genes and microbubbles (MBs) has been limited. The feasibility of transendocardially delivering MBs as extracellular markers and gene carriers in conjunction with intracardiac ultrasound (US) treatment remains unknown. In a canine acute myocardial infarction (MI) model, a naked plasmid encoding 500 μg human hepatocyte growth factor (HGF) was delivered transendocardially to the myocardium via US/MB (HGF-US/MB), insonation (HGF-US), or alone (HGF alone). Control MI dogs received saline by US/MB (control group). During US/MB, intracardiac insonation was performed for 30 s with a 10-s pause, at 4.3-MHz, 1-W/cm2, for 60 s at each site. Gene and MB distribution in the myocardium was visualized. Compared to the HGF alone group at 28 days, the HGF-US/MB group had an average 7.1-fold enhancement in gene expression (P < 0.01). Compared to the control group, there were 16% decreases in the ratio of left ventricle (LV) weight/body weight in the HGF-US/MB group and decreases in collagen volume fraction (CVF) of type I (33%) and type III (23%) collagen. Capillary density increased from 22.8 ± 6.3/mm2 in the control group to 154.3 ± 42.9/mm2 in the HGF-US/MB group (P < 0.01). This less invasive catheter-based US therapeutic procedure offers observable gene delivery with higher therapeutic efficiency, enhanced angiogenesis, and improved myocardial perfusion and ventricular function following MI.
Current Gene Therapy 11/2012; · 3.39 Impact Factor
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ABSTRACT: Resveratrol is a polyphenolic flavonoid found in a diversity of plants, especially berry fruits and is a popular nutritional supplement. It is known to have antioxidant, anti-inflammatory, and anticarcinogenic properties. Recently, additional evidence has been found that resveratrol is beneficial to metabolic and cardiovascular health and may increase the life expectancy of various organisms. These biological effects are widely believed to be due to the ability of resveratrol to activate silent mating-type information regulation 2 homolog 1, a nicotinamide adenine dinucleotide-dependent deacetylase. However, other research has shown that 5'-adenosine monophosphate-activated kinase and not silent mating-type information regulation 2 homolog 1 may be the target of resveratrol. A recent study reported that resveratrol directly inhibits cyclic adenosine monophosphate-specific phosphodiesterases and then activates 5'-adenosine monophosphate-activated kinase. Therefore, the mechanism underlying the diverse nutritional and therapeutic activities of resveratrol needs to be further explored. Furthermore, the optimal dose and possible adverse effects of resveratrol in humans are completely clear. The purpose of this review is to present some of the newly discovered biological effects of resveratrol, including autophagy and stem cell regulation, and research opportunities for the application of resveratrol in cardiovascular and metabolic health. Described herein is the recent understanding of the mechanism of action of resveratrol and future research directions to ascertain the potential of this flavonoid that is present in food.
Nutrition research (New York, N.Y.) 09/2012; 32(9):648-58. · 1.20 Impact Factor
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ABSTRACT: BACKGROUND: Glycoprotein (Gp) IIb/IIIa inhibitors are beneficial for patients with ST-segment elevation myocardial infarction (STEMI) undergoing percutaneous coronary intervention (PCI). However, optimal drug timing remains inconclusive. Therefore, this study was to perform a meta-analysis of the clinical efficiency and safety of early versus late GpIIb/IIIa inhibitors in STEMI patients undergoing PCI. METHODS: A comprehensive search was to identify randomized trials of early versus late GpIIb/IIIa inhibitors in STEMI patients undergoing PCI. The GpIIb/IIIa inhibitors were abciximab and small-molecular Gp inhibitors (SMGP) namely eptifibatide and tirofiban. The efficacy endpoints included pre-procedural Thrombolysis in Myocardial Infarction (TIMI) grade 3 flow, post-procedural TIMI 3 flow, complete ST-segment resolution, left ventricle ejection fraction (LVEF), and mortality. The safety endpoint was the occurrence of major bleeding complications. RESULTS: Nineteen trials were included in the meta-analysis, involving 4209 patients (early 2124 versus late 2085). Early GpIIb/IIIa inhibitors significantly improved pre-procedural TIMI 3 flow, while early abciximab, but not SMGP, further enhanced post-procedural TIMI 3 flow, complete ST-segment resolution, LVEF, and reduced six-month mortality. In addition to clopidogrel loading, only early abciximab improved pre-procedural TIMI 3 flow and complete ST-segment resolution. The rate of major bleeding complications was not increased in early GpIIb/IIIa inhibitors with/without clopidogrel loading. CONCLUSIONS: Early GpIIb/IIIa inhibitors improved pre-procedural TIMI 3 flow and early abciximab provided favorable clinical outcomes in STEMI patients undergoing PCI. On the basis of clopidogrel loading, early abciximab enhanced pre-procedural TIMI 3 flow and ST-segment resolution. These beneficial effects were achieved without increased risks of major bleeding complications.
International journal of cardiology 07/2012; · 7.08 Impact Factor
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ABSTRACT: The aim of this study was to prove that an intramyocardial injection of a mixture of low-dose human growth factor (HGF) plasmid and microbubbles (MB) in combination with insonation was an effective therapy for myocardial infarction.
Twenty dogs with myocardial infarction were divided into 4 groups: (1) HGF, MB and ultrasound (HGF-US/MB), (2) HGF and US (HGF-US), (3) HGF alone and (4) surgery alone (control). In the HGF-US/MB group, HGF plasmid DNA (500 μg) mixed with 0.5 ml of MB solution was injected 5 min after coronary occlusion followed by insonation. With the exception of the control group, the other dogs were divided into two groups, one treated with the HGF gene and insonation and the other with the HGF gene only.
Compared to the HGF group, infarct size decreased from 32%±7% (control) to 23%±5% in the HGF-US/MB group 28 d later (P<0.05). Capillary density increased from 21.7±4.2/mm(2) (control) to 114.3±28.9/mm(2) in the HGF-US/MB group (P<0.01). Compared to the HGF group, there was a 14% decrease in the ratio of left ventricle weight/body weight and a 25% decrease in hydroxyproline content. We also observed a 29% and 20% decrease in collagen volume fraction of type I and type III collagen, respectively in the HGF-US/MB group.
Intramyocardial injection of HGF and MB in combination with insonation enhances neovascularization and reduces ventricular remodeling and infarct size.
Life sciences 03/2012; 90(17-18):695-702. · 2.56 Impact Factor
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ABSTRACT: This study presents a novel method that direct intramyocardial injection of low-dose plasmid DNA and microbubbles combined with insonation could further augment gene expression in normal and ischemic canine myocardium. Plasmids encoding enhanced green fluorescent protein (pEGFP) and hepatocyte growth factor (pHGF) (500 μg) were individually mixed with 0.5 ml of microbubble solution (MB) and injected into the normal or acute ischemic canine myocardium. The dogs in the plasmid + MB/US group underwent insonation (US). Other dogs were randomly divided into three treatment groups: plasmid and insonation, plasmid and MB injection, and plasmid injection only. The EGFP and HGF mRNA expressions were assessed in the myocardium at the injection site and at sites 0.5 and 1 cm remote from the injection site. Compared to plasmid transfer alone, a mean 13.4-fold enhancement of gene expression was achieved in the EGFP + MB/US group at 48 h (p < 0.01). HGF mRNA expression in ischemic zones was markedly elevated after 28 days, with a mean 9.0-fold enhancement in the HGF + MB/US group (p < 0.01). EGFP protein expression was detected in the normal myocardium at 1 cm remote from the injection site in the EGFP + MB/US group. Similarly, HGF protein expression was detected in the ischemic myocardium at 0.5 cm remote from the injection site in the HGF + MB/US group. These findings indicate that the radius of gene expression was partly extended in the two plasmid + MB/US groups. The capillary density increased from 20.9 ± 5.3/mm(2) in control myocardial infarction dogs without treatment to 126.7 ± 38.2/mm(2) in the HGF + MB/US group (p < 0.01). Taken together, the present data demonstrate that direct intramyocardial injection of an angiogenic gene and microbubbles combined with insonation can augment gene expression and angiogenesis. Consequently, this strategy may be a useful tool for gene therapy of ischemic heart disease.
Heart and Vessels 06/2011; 27(3):316-26. · 2.05 Impact Factor
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ABSTRACT: This study was designed to investigate the protective effect of tetramethylpyrazine isolated from Ligusticum chuanxiong, a traditional Chinese medicine, on diabetic nephropathy in a rat model, and to explore the possible mechanism involved in a protective function.
Diabetes was induced in male Sprague-Dawley rats by a single intraperitoneal injection of 70mg/kg of streptozotocin. One week later, 200mg/kg/day of tetramethylpyrazine was administered intragastric gavage daily for 8 weeks. Renal functions and expression of vascular endothelial growth factor were examined at 4 and 8 weeks after tetramethylpyrazine administration.
Blood glucose and renal function were significantly improved in the tetramethylpyrazine-treated group compared to the untreated diabetic rats. Diabetic nephropathy resulted in an increase in the expression of vascular endothelial growth factor, while tetramethylpyrazine administration greatly decreased the expression.
Our results suggest that administration of tetramethylpyrazine may reduce kidney damage caused by diabetes. This protective effect may be mediated, in part, by downregulated expression of vascular endothelial growth factor in the kidney.
Phytomedicine: international journal of phytotherapy and phytopharmacology 06/2011; 18(13):1148-52. · 2.17 Impact Factor
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ABSTRACT: To study the differences in pathogen distribution and antibiotic susceptibility between patients with COPD exacerbation and patients with community-acquired pneumonia, and develop guidance for antibiotic treatment of those conditions.
We retrospectively analyzed the medical records of 586 COPD-exacerbation patients and 345 community-acquired-pneumonia patients from January 2007 to December 2008, including sputum culture results, antibiotic susceptibilities of the microorganisms, and clinical characteristics.
276 (47%) of the COPD-exacerbation patients, and 183 (53%) of the community-acquired-pneumonia patients had a positive sputum culture. In order, the most common pathogens in the COPD-exacerbation patients were Pseudomonas aeruginosa, Escherichia coli, Klebsiella pneumoniae, Staphylococcus aureus, Acinetobacter baumannii, and Haemophilus influenzae. The most common pathogens in the community-acquired-pneumonia patients were Streptococcus pneumoniae, H. influenzae, K. pneumoniae, S. aureus, and E. coli.
P. aeruginosa was the most common pathogen in our patients with COPD exacerbation, and S. pneumoniae was the most common in our patients with community-acquired pneumonia. P. aeruginosa is especially common in the patients with serious or extremely serious COPD.
Respiratory care 05/2011; 56(11):1818-24. · 2.01 Impact Factor
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ABSTRACT: To enhance myocardial angiogenic gene expression, a novel gene delivery strategy was tested. Direct intramyocardial injection of an angiogenic gene with microbubbles and insonation were applied in a dog animal model. Dogs received one of the four different treatments in conjunction with either the enhanced green fluorescence protein (EGFP) gene or the hepatocyte growth factor (HGF) gene: gene with microbubbles (MB) and ultrasound (US); gene with US; gene with MB; or the gene alone.
Distribution of MB and the gene in the myocardium was visualized during the experiment. Compared with the EGFP gene group, an average 14.7-fold enhancement in gene expression was achieved in the EGFP+MB/US group (P < 0.01). Compared with the HGF gene group, an average 10.7-fold enhancement in gene expression was achieved in the HGF+MB/US group (P < 0.01). In addition, capillary density increased from 20.8 ± 3.4/mm2 in the HGF gene group to 146.7 ± 31.4/mm2 in HGF+MB/US group (P < 0.01).
Thus, direct intramyocardial injection of an angiogenic gene in conjunction with microbubbles plus insonation synergistically enhances angiogenesis. This method offers an observable gene delivery procedure with enhanced expression efficiency of the delivered gene.
BMC Biotechnology 01/2011; 11:56. · 2.35 Impact Factor
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International journal of cardiology 12/2010; 145(3):583-4. · 7.08 Impact Factor
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ABSTRACT: Cardiovascular diseases remain the leading cause of mortality worldwide. Recent studies of AMP-activated protein kinase (AMPK), a highly conserved sensor of cellular energy status, suggest that there might be therapeutic value in targeting the AMPK signaling pathway. AMPK is found in most mammalian tissues, including those of the cardiovascular system. As cardiovascular diseases are typically associated with blood flow occlusion and blood occlusion may induce rapid energy deficit, AMPK activation may occur during the early phase upon nutrient deprivation in cardiovascular organs. Therefore, investigation of AMPK in cardiovascular organs may help us to understand the pathophysiology of defence mechanisms in these organs. Recent studies have provided proof of concept for the idea that AMPK is protective in heart as well as in vascular endothelial and smooth muscle cells. Moreover, dysfunction of the AMPK signalling pathway is involved in the genesis and development of various cardiovascular diseases, including atherosclerosis, hypertension and stroke. The roles of AMPK in the cardiovascular system, as they are currently understood, will be presented in this review. The interaction between AMPK and other cardiovascular signalling pathways such as nitric oxide signalling is also discussed.
Journal of Cellular and Molecular Medicine 11/2010; 14(11):2604-13. · 4.13 Impact Factor
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ABSTRACT: Lipopolysaccharide (LPS) induces the expression of a wide range of pro-inflammatory mediators via NF-kappaB activation. These pro-inflammatory cytokines, such as tumor necrosis factor-alpha (TNF-alpha) and interleukin-1beta (IL-1beta), may be important in triggering atherogenesis. We have previously observed that actinonin, a meprin inhibitor, suppressed the formation of atherosclerotic plaques and, in in vitro experiments, actinonin also had an effect on the way LPS altered THP-1 cell function. The aim of the present study was to investigate whether meprin-alpha regulates LPS-induced production of TNF-alpha and IL-1beta in peripheral blood mononuclear cells (PBMCs) and its potential mechanisms of action. We observed that meprin-alpha could enhance LPS-induced expression of TNF-alpha and IL-1beta mRNA and protein in a time- and concentration-dependent manner, assessed using real-time PCR and ELISA. Meprin-alpha also significantly increased LPS-induced NF-kappaB transcriptional activity. Furthermore, we assessed the effects of meprin-alpha specific siRNA on the production of TNF-alpha and IL-1beta to examine whether meprin-alpha was involved in the process of LPS-induced activation of PBMCs. Our results show that LPS-induced IL-1beta and TNF-alpha production by PBMCs was significantly reversed by meprin-alpha specific siRNA. In addition, the augmentation of meprin-alpha of the LPS-induced expression of TNF-alpha and IL-1beta was significantly decreased by Bay-117082, an inhibitor of NF-kappaB. In conclusion, our data indicate that meprin-alpha is capable of increasing LPS-induced production of cytokines in peripheral blood mononuclear cells, which might be associated with the activation of NF-kappaB.
Regulatory Peptides 12/2009; 160(1-3):99-105. · 2.11 Impact Factor
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ABSTRACT: Mice with defects in the Klotho gene exhibit multiple aging phenotypes including arteriosclerosis. We hypothesised that the G-395A polymorphism in the promoter region of the human Klotho gene may contribute to the prevalence of Essential Hypertension (EH).
We investigate whether the G-395A polymorphism of Klotho is associated with EH in a population consisting of 215 patients with EH and 220 non-hypertensive subjects. We also tested whether a G/A substitution at the G-395A site affected the transcription level in vitro through the dual-luciferase reporter assay.
Differences in the genotype distributions of the G-395A polymorphism between the EH and non-hypertension groups are statistically significant (P=0.032). There are differential effects of age, gender and smoking status on the association of the G-395A polymorphism with EH; the G-395A polymorphism is significantly associated with EH in subjects over 60years old, in females and in nonsmokers. A multiple logistic regression analysis indicated that the odds ratio for EH in the -395A allele carriers as compared with the control group was 0.593 (P=0.024) after adjusting for current traditional risk factors. The dual-luciferase reporter assay revealed that the -395A carrier of a 498-bp DNA fragment (containing the G-395A site) upstream of the Klotho gene has higher relative luciferase activity than the -395G carrier.
The G-395A polymorphism of the human Klotho gene is associated with EH and may be a potential regulatory site.
Clinica chimica acta; international journal of clinical chemistry 12/2009; 411(5-6):386-90. · 2.54 Impact Factor
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Zhonghua xin xue guan bing za zhi [Chinese journal of cardiovascular diseases] 08/2008; 36(7):593.
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ABSTRACT: To investigate the influence of pinacidil preconditioning on the protection of the structure and respiratory function of injured myocardial mitochondria in scalded rats.
Seventy-five healthy Wistar rats, weighed 250 approximately 300 g, were randomly divided into three groups: i.e. control (n = 9, with intraperitoneal injection of 50 microg/kg isotonic saline), scald (n = 33, with 30% TBSA full thickness scald) and pre-conditioning (n = 33, with same extent of scald injury after intraperitoneal injection of 50 microg/kg pinacidil) groups. Mitochondrial ultrastructure was observed by transmission electron microscope. The mitochondrial respiratory function, the MDA content and the superoxide anion level were determined with corresponding methods.
The degree of injury to rat myocardial mitochondria in pre-conditioning group was less intensive than that in scald group (P < 0.05 or 0.01). The respiratory control rate in pre-conditioning group was obviously higher than that in scald group (P < 0.05), and the contents of MDA and superoxide anion in pre-conditioning group were markedly lower than those in scald group (P < 0.05 or 0.01), as evidenced by their contents at 3 post scalding hours (0.60 +/- 0.09 micromol/g and 0.127 +/- 0.020) were obviously lower than those in scald group (0.83 +/- 0.07 micromol/g and 0.169 +/- 0.015) (P < 0.01).
Pinacidil preconditioning was beneficial in the protection of myocardial mitochondria in scalded rats, and it might be related to the pre-opening of potassium channel which was sensitive to mitochondrial ATP.
Zhonghua shao shang za zhi = Zhonghua shaoshang zazhi = Chinese journal of burns 06/2005; 21(3):170-2.
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ABSTRACT: To investigate the changes in binding features of (3)H -Ryanodine cardiac myocytic nuclei in reperfusion injury in the rat, and the effects of phosphorylation regulation on the binding characteristics.
Healthy male Wistar rats were randomly divided into ischemia/reperfusion injury (IRI) group and sham-operation group. IRI model was reproduced by ligating the left main coronary artery for 30 minutes followed by reperfusion of the heart for 3 hours, while in the sham-operation group the animals underwent a thoracotomy only for 3.5 hours. Cardiac myocytic nuclei were isolated by sucrose density gradient centrifugation. The maximum binding capacity (Bmax) and the dissociating ratio (Kd) of Ryanodine receptors (RyRs) were measured by radioligand binding analysis as well as Scatchard plot.
There was a high affinity of RyRs to bind with (3)H-Ryanodine on the nuclear wall of rat cardiac myocytic nucleus. Compared with that of the sham-operation group, Bmax of RyRs of IRI cardiac myocytic nuclei was decreased by 29% (P<0.01), but there was no difference in Kd between two groups(P>0.05). With phosphorylation by activating the endogenous protein kinase C(PKC) with phorbol myristate acetate (PMA)+phosphatidyl serine(PS), Bmax of both sham and IRI groups were increased markedly (P<0.01), but in the latter group it was less increased (P<0.01). With phosphorylation by Ca(2+)-calmodulin (CaM), Bmax was decreased in both sham-operation and IRI groups (both P<0.05), but was less decreased in the latter(P<0.01). However, both PMA+PS and Ca(2+)-CaM did not change the Kd of nuclear RyR in either group (both P>0.05).
After IRI, Bmax of (3)H -Ryanodine of cardiac myocytic nuclei is decreased and the impact of PMA+PS and Ca(2+)-CaM on the Bmax is impaired, but the affinity of (3)H -Ryanodine to cardiac myocytic nuclei is not altered under above circumstances.
Zhongguo wei zhong bing ji jiu yi xue = Chinese critical care medicine = Zhongguo weizhongbing jijiuyixue 03/2005; 17(3):146-9.
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ABSTRACT: To observe the alteration of cardiac myocyte nuclear inositol 1,3,4,5-tetrakisphosphate receptor (IP(4)R) binding properties in rat subjected to myocardial ischemic reperfusion in order to further make it clear whether this change is involved in the molecule mechanism of cell apoptosis of rat with myocardial ischemic reperfusion.
Extracting of cardiac myocyte nucleus was accomplished by saccharose density gradient centrifugation method, the binding properties of nuclear IP(4)R in different conditions were detected by radioligand binding assay. Apoptosis index of myocardial cell was determined by using TUNEL assay.
(1) Myocardial cell apoptosis index in rat heart underwent 30 min regional ischemia and 3 h reperfusion increased distinctly compared with that in control group (P < 0.01). (2) There were two IP(4) binding sites located to the nuclear envelope. (3) In ischemic reperfusion injury (IRI) group, Bmax from high affinity binding site of nuclear IP(4)R significantly increased compared with that in sham-operated group, whereas Bmax from low affinity binding site didn't change. Kd values of both sites were all significantly decreased by 63% and 55%, respectively. (4) Phosphorylation of nuclear IP(4)R by PKC increased markedly its binding ability both in IRI and control group (P < 0.05), which was more apparent in IRI group. (5) In sham-operated group, the binding ability of nuclear IP(4)R increased with increasing free calcium concentrations in cytoplasm, and the binding properties of IP(4)R in IRI group were also increased in the condition of calcium overloading.
The increasing of binding properties of nuclear IP(4)R from ischemic reperfusion heart may be one of important mechanism involved in myocardial cell apoptosis, furthermore resulting in myocardial IRI.
Zhonghua xin xue guan bing za zhi [Chinese journal of cardiovascular diseases] 02/2005; 33(2):161-5.
