OBJECTIVESTo investigate the protective effects of Sapindus saponins in spontaneously hypertensive rats, and the possible cellular and molecular mechanisms.

METHODSThirty-two 16-week-old spontaneously hypertensive rats were randomly divided into four groups (8 in each group): model group (placebo), positive control group (27 mg/kg of Captopril Tablets), Sapindus saponins groups (27 mg/kg and 108 mg/kg, respectively). Another 8 healthy Wistar-Kyoto strain (WKY) rats were used as the normal group. The animals were treated for 8 weeks. Blood pressure of rats was determined by non-invasive blood pressure meter (BP-6). Furthermore, the contents of angiotensin II (Ang II) in plasma and myocardial tissue were determined by enzyme-linked immunosorbent assay (ELISA), the gene expression of receptor angiotensin type 1 (AT1R) in aorta was determined by quantitative realtime polymerase chain reaction (qRT-PCR). The protein expression of transforming growth factor-β1 (TGF-β1) and AT1R in heart was determined by immunohistochemical staining. The protein expression of p-phosphorylation of p38 mitogen-activated protein kinase (p-p38MAPK) was determined by Western blotting. The contents of interleukin (IL)-1, IL-6 and tumor necrosis factor (TNF) in serum were determined by radioimmunoassay. And the histopathological and morphological changes of aorta and heart tissue samples were assessed semi-quantitatively by hematoxylin-eosin (HE) or Masson staining.

RESULTSThirty minutes after single or continuous treatment, systolic blood pressure (SBP) was reduced significantly in Sapindus saponins groups. And the contents of AngII, IL-1, IL-6 and TNF-α in serum, the expression of AT1R mRNA, p-p38MAPK and TGF-β1 were significantly suppressed dose-dependently (P<0.05 or P<0.01). With the Sapindus saponins treatment, compared with those of the model group, the cardiac and aortic pathological changes were ameliorated significantly.

CONCLUSIONSOur findings suggest that Sapindus saponins might have protective effects in spontaneously hypertensive rats, the cellular and molecular mechanisms of which might be relevant to the regulation of inflammatory responses mediated by p-p38MAPK signal pathway based on activated Ang II and AT1R.

Angiotensin II ; metabolism ; Animals ; Aorta ; drug effects ; pathology ; physiopathology ; Blood Pressure ; drug effects ; Collagen ; metabolism ; Female ; Hypertension ; blood ; drug therapy ; enzymology ; physiopathology ; Interleukin-1 ; blood ; Interleukin-6 ; blood ; Male ; Phosphorylation ; drug effects ; Protective Agents ; pharmacology ; therapeutic use ; Rats, Inbred SHR ; Receptor, Angiotensin, Type 1 ; metabolism ; Renin-Angiotensin System ; drug effects ; Sapindus ; chemistry ; Saponins ; pharmacology ; therapeutic use ; Transforming Growth Factor beta1 ; metabolism ; Tumor Necrosis Factor-alpha ; blood ; p38 Mitogen-Activated Protein Kinases ; metabolism

OBJECTIVETo observe the effect of sesamin (Ses) on pulmonary vascular remodeling in rats with monocrotaline ( MCT)-induced pulmonary hypertension (PH).

METHODTotally 48 male Sprague-Dawley (SD) rats were fed adaptively for one week and then divided into the normal control group, the MCT group, the MCT +Ses (50 mg x kg(-1)) group and the MCT + Ses (100 mg x kg(-1)) group, with 12 rats in each group. The PH rat model was induced through the subcutaneous injection with MCT(60 mg x kg(-1)). After the administration for four weeks, efforts were made to measure the right ventricular systolic pressure( RVSP) and mean pulmonary artery pressure (mPAP) through right jugular vein catheterization, and isolate right ventricle( RV) and left ventricle( LV) +septum (S) and measure their length to calculate RV/ ( LV + S) and ratio of RV to tibial length. Pathologic changes in arterioles were observed by HE staining. Masson's trichrome stain was used to demonstrate changes in collagen deposition of arterioles. The alpha-smooth muscle actin (alpha-SMA) expression in pulmonary arteries was measured by immunohistochemisty. The total antioxidative capacity (T-AOC) and malondialdehyde (MDA) content in pulmonary arteries were determined by the colorimetric method. The protein expressions of collagen I, NOX2 and NOX4 were analyzed by Real-time PCR and Western blot.

RESULTAfter the administration for 4 weeks, Ses could attenuate RVSP and mPAP induced by MCT, RV/ (LV + S) and ratio of RV to Tibial length, alpha-SMA and collagen I expressions and remodeling of pulmonary vessels and right ventricle. Meanwhile, Ses could obviously inhibit the expressions of NOX2, NOX4 and MDA content and increase T-AOC.

CONCLUSIONSesamin could ameliorate pulmonary vascular remodeling induced by monocrotaline in PH rats. Its mechanism may be related to expressions of NOX2 and NOX4 expression and reduction in oxidative stress injury.

Animals ; Dioxoles ; administration & dosage ; Disease Models, Animal ; Drugs, Chinese Herbal ; administration & dosage ; Humans ; Hypertension, Pulmonary ; drug therapy ; enzymology ; genetics ; physiopathology ; Lignans ; administration & dosage ; Lung ; blood supply ; enzymology ; metabolism ; Male ; Membrane Glycoproteins ; genetics ; metabolism ; Monocrotaline ; adverse effects ; NADPH Oxidase 2 ; NADPH Oxidase 4 ; NADPH Oxidases ; genetics ; metabolism ; Pulmonary Artery ; drug effects ; metabolism ; physiopathology ; Rats ; Rats, Sprague-Dawley ; Vascular Remodeling ; drug effects

OBJECTIVETo investigate the effect of panax notoginseng saponins (PNS) injection on pulmonary artery pressure and the expression of p38MAPK in lung tissue of rats subjected to chronic hypoxia.

METHODSThirty adult male Sprague Dawley rats were randomly divided into three groups (ten in each group): rats in control group were exposed to normoxic condition and the rats in hypoxia group and PNS group were subjected to 4-week hypoxia, and PNS injection (50 mg · kg(-1) · d(-1)) was administrated intraperitoneally at 30 min in the PNS group daily before the rats were kept in the hypoxic chamber, while rats in the other two groups received equal dose of normal saline instead. After chronic hypoxia, mean pulmonary artery pressure (mPAP) and mean carotid artery pressure (mCAP) were measured. The heart and lung tissues were harvested, and right ventricle (RV) and left ventricle plus ventricular septum (LV+S) were weighed to calculate the ratio of RV/(LV+S). The expression of p38MAPK mRNA was determined by reverse transcription-polymerase chain reaction, the quantity of phosphorylated p38MAPK (p-p38MAPK) in rat lung tissues and pulmonary arterioles was determined by Western blot and immunohistochemistry.

RESULTSCompared with the control group, mPAP and the ratio of RV/(LV+S) in the hypoxia group were increased, the expression of p-p38MAPK in pulmonary arterioles and p38MAPK mRNA in the lung were higher (P<0.05). The changes of these parameters in the hypoxia group were significantly attenuated by PNS treatment (P<0.05).

CONCLUSIONPNS injection was shown to prevent hypoxic pulmonary hypertension at least partly by regulating p38MAPK pathway.

Animals ; Arterioles ; drug effects ; metabolism ; Blood Pressure ; drug effects ; Blotting, Western ; Carotid Arteries ; drug effects ; physiopathology ; Disease Models, Animal ; Heart Ventricles ; drug effects ; physiopathology ; Hemodynamics ; drug effects ; Hypertension, Pulmonary ; complications ; enzymology ; physiopathology ; Hypoxia ; complications ; enzymology ; physiopathology ; Injections ; Lung ; drug effects ; enzymology ; pathology ; physiopathology ; MAP Kinase Signaling System ; drug effects ; Male ; Panax notoginseng ; chemistry ; Pulmonary Artery ; drug effects ; physiopathology ; RNA, Messenger ; genetics ; metabolism ; Rats, Sprague-Dawley ; Saponins ; administration & dosage ; pharmacology ; p38 Mitogen-Activated Protein Kinases ; genetics ; metabolism

The purpose of this study was to investigate the therapeutic effects of small hairpin RNA (shRNA) targeting endothelin-converting enzyme (ECE)-1 in monocrotaline (MCT)-induced pulmonary hypertensive rats. Ninty-four Sprague-Dawley rats were divided into three groups: control (n = 24), MCT (n = 35) and shRNA (n = 35). Four-week survival rate in the shRNA group was significantly increased compared to that in the MCT group. The shRNA group showed a significant improvement of right ventricular (RV) pressure compared with the MCT group. The MCT and shRNA groups also showed an increase in RV/(left ventricle + septum) ratio and lung/body weight. Plasma endothelin (ET)-1 concentrations in the shRNA group were lower than those in the MCT group. Medial wall thickness of pulmonary arterioles were increased after MCT injection and was significantly decreased in the shRNA group. The number of intra-acinar muscular pulmonary arteries was decreased in the shRNA group. The mRNA expressions of ET-1 and ET receptor A (ETA) were significantly decreased in the shRNA group in week 4. The protein levels of ETA were decreased in the shRNA group in week 2. The protein levels of tumor necrosis factor-alpha and vascular endothelial growth factor were decreased in the shRNA group in week 4. In conclusion, the gene silencing with lentiviral vector targeting ECE-1 could be effective against hemodynamic, histopathological and gene expression changes in pulmonary hypertension.
Animals ; Aspartic Acid Endopeptidases/*antagonists & inhibitors/blood/genetics ; Body Weight ; Heart Ventricles/physiopathology ; Hypertension, Pulmonary/chemically induced/*enzymology/mortality ; Lentivirus/genetics ; Lung/anatomy & histology/metabolism/pathology ; Male ; Metalloendopeptidases/*antagonists & inhibitors/blood/genetics ; Monocrotaline/toxicity ; Pulmonary Artery/drug effects/physiopathology ; RNA, Small Interfering/*metabolism ; Rats ; Rats, Sprague-Dawley ; Receptor, Endothelin A/genetics/metabolism ; Survival Rate ; Tumor Necrosis Factor-alpha/metabolism ; Vascular Endothelial Growth Factor A/metabolism

OBJECTIVE: To investigate the impact of renal denervation on the blood pressure, plasma renalase content and expression of renalase and tyrosine hydroxylase (TH) in the idney of spontaneous hypertensive (SH) rats and to explore the role of renal denervation in lowering the blood pressure. METHODS: SH rats were randomly assigned into a baseline group, a surgery (renal denervation) group, a sham group and a control group (n=48). WKY rats matched in age (n=12) served as a baseline control group. All rats were housed until 12 weeks old. Then, the rats in the baseline group and the WKY group were sacrificed whose blood and kidney were collected for examination. In the renal denervation group, the sham group and the control group, the blood pressure was monitored continuously. One week and 6 weeks after the renal denervation, 6 rats in each group were sacrificed whose blood and kidney were collected. ELISA was employed to measure the plasma renalase and Western blot assay done to detect the expression of TH and renalase in the kidney. RESULTS: Compared with WKY rats, blood pressure significantly increased and TH protein expression markedly elevated (P<0.05) in SH rats in the baseline group, but plasma renalase content and protein expression of renalase in the kidney dramatically reduced (P<0.05). One week after the surgery, the mean arterial pressure and TH protein expression in the surgery group were lowered compared with the baseline group and dramatically reduced compared with the sham group and the control group (P<0.05). In the surgery group, the renalase level was markedly increased compared with the baseline group, the sham group, and the control group (P<0.05). Six weeks after the renal denervation, the mean arterial pressure and TH level in the surgery group were significantly increased but the renalase content and expression markedly reduced compared with those 1 week, but there were no marked differences among the surgery group, the sham group, and the control group (P>0.05). No pronounced differences in the above variables were found between the sham group and the control group at any time point (P>0.05). CONCLUSION Renal denervation can lower the blood pressure, which may attribute to the suppression of sympathetic nerves, increase in plasma renalase content and renalase expression in the kidney.
Animals ; Blood Pressure ; physiology ; Hypertension ; surgery ; Kidney ; enzymology ; innervation ; Male ; Monoamine Oxidase ; blood ; metabolism ; Rats ; Rats, Inbred SHR ; Sympathectomy ; methods ; Sympathetic Nervous System ; physiopathology ; Tyrosine 3-Monooxygenase ; metabolism

OBJECTIVETo explore the impact of sulfur dioxide (SO(2)) on hydrogen sulfide (H(2)S)/cystathionine-γ-lyase (CSE) and H(2)S/mercaptopyruvate sulfurtransferase (MPST) pathways in the pathogenesis of hypoxic pulmonary hypertension.

METHODSThirty-two male Wistar rats were randomly divided into four groups: control group (n = 8), hypoxic group (n = 8), hypoxic + SO(2) group (n = 8) and hypoxic + hydroxamate (HDX) group (n = 8). After 21 days of experiment, the concentration and production of H(2)S in lung tissues were measured respectively for each rat. The protein expression of CSE and MPST in intima and media of small pulmonary arteries in rats was detected with immunohistochemical method.

RESULTSCompared with control group, the mean pulmonary artery pressure (mPAP) in rats of hypoxic group was increased significantly [(33.38 ± 6.32) mm Hg vs. (16.74 ± 3.81) mm Hg, P < 0.01]. Compared with hypoxic group, the mPAP in rats of hypoxic + SO(2) group was decreased significantly [(29.65 ± 2.53) mm Hg vs. (33.38 ± 6.32) mm Hg, P < 0.01]. However, compared with hypoxic group, the mPAP in rats of hypoxic + HDX group was increased significantly [(39.44 ± 6.26) mm Hg vs. (33.38 ± 6.32) mm Hg, P < 0.01]. Compared with control group, the concentration [(2.02 ± 0.43) µmol/g vs. (3.11 ± 0.42) µmol/g, P < 0.01] and production [(19.64 ± 3.48) nmol/(g·min)vs. (28.20 ± 5.95) nmol/(g·min), P < 0.05] of H(2)S were decreased significantly in rats of hypoxic group, respectively. When treated with SO(2), hypoxic rats showed an increased concentration [(2.73 ± 0.20) µmol/g vs. (2.02 ± 0.43) µmol/g, P < 0.01] and production [(26.24 ± 1.92) nmol/(g·min) vs. (19.64 ± 3.48) nmol/(g·min), P < 0.01] of H(2)S in lung tissue compared with those without receiving SO(2) treatment. When treated with HDX, hypoxic rats showed a significant decrease in concentration [(1.64 ± 0.23) µmol/g vs. (2.02 ± 0.43) µmol/g, P < 0.05] and production [(13.94 ± 3.63) nmol/(g·min) vs. (19.64 ± 3.48) nmol/(g·min), P < 0.05] of H(2)S in lung tissue compared with those without receiving HDX treatment. As for the expression of CSE in small pulmonary arteries (SPAs), compared with control group, the expression of CSE in intima [(0.31 ± 0.02) vs. (0.36 ± 0.01), P < 0.01] and media [(0.27 ± 0.01) vs. (0.30 ± 0.01), P < 0.01] in rats of hypoxic group was decreased significantly. While compared with hypoxic group, the expression of CSE in intima [(0.35 ± 0.02) vs. (0.31 ± 0.02), P < 0.01] in SPAs of hypoxic + SO(2) group was increased significantly. With HDX treatment, the expression of CSE in intima [(0.26 ± 0.01) vs. (0.31 ± 0.02), P < 0.01] in SPAs of hypoxic group was lower than that without HDX treatment. As for the expression of MPST in SPAs, compared with hypoxic group, the expression of MPST in media [(0.32 ± 0.02) vs. (0.29 ± 0.01), P < 0.01] in SPAs of hypoxic + SO(2) group was increased significantly.

CONCLUSIONSO(2) might upregulate H(2)S/CSE and H(2)S/MPST pathways in pulmonary arteries of hypoxic rats.

Animals ; Cystathionine gamma-Lyase ; metabolism ; Hydrogen Sulfide ; metabolism ; Hypertension, Pulmonary ; enzymology ; physiopathology ; Hypoxia ; metabolism ; physiopathology ; Male ; Pulmonary Artery ; metabolism ; physiopathology ; Rats ; Rats, Wistar ; Sulfur Dioxide ; pharmacology ; Sulfurtransferases ; metabolism

OBJECTIVETo evaluate the liver injury in rats of abdominal infection complicated with abdominal compartment syndrome(ACS).

METHODSSD rats were divided into four groups, including the sham group, the abdominal infection group, the ACS group, and the abdominal infection plus ACS group (combination group). Rats were sacrificed at 1 h, 6 h, 12 h, 24 h after operation with 6 rats at each time point. Blood specimens were collected for liver function testing. Liver tissues were assessed by pathologically examination with hepatic injury severity scoring(HISS). The expressions of Toll-like receptor 4 (TLR4),TNF-α and IL-6 were examined by reverse transcription- polymerase chain reaction.

RESULTSAt 24 h after operation, as compared to the sham group(18.2±1.3) U/L and (105.6±25.5) U/L, ALT and AST increased obviously in the abdominal infection group(68.2±17.5) U/L and (184.6±36.1) U/L, the ACS group (305.2±128.2) U/L and (638.0±104.8) U/L and the combination group (409.2±67.1) U/L and (743.2±250.2) U/L, while the combination group had a higher level as compared to the infection group and the ACS group(all P<0.05). HISS scores were significantly higher in the abdominal infection group(5.0), the ACS group(5.5) and the combination group(7.0) as compared to the sham group(1.5), but no significant differences were found among the three groups at 24 h after operation. Expressions of TLR4, TNF-α and IL-6 were significantly higher in combination group than those in the other three groups.

CONCLUSIONSLiver function can be affected by abdominal infection and ACS. Abdominal infection plus ACS results in more severe liver injury.

Alanine Transaminase ; blood ; Animals ; Aspartate Aminotransferases ; blood ; Disease Models, Animal ; Female ; Interleukin-6 ; metabolism ; Intra-Abdominal Hypertension ; enzymology ; physiopathology ; Intraabdominal Infections ; enzymology ; physiopathology ; Liver ; physiopathology ; Rats ; Rats, Sprague-Dawley ; Toll-Like Receptor 4 ; metabolism ; Tumor Necrosis Factor-alpha ; metabolism

OBJECTIVE: To investigate whether atorvastatin treatment can improve the symptoms of hypoxia-induced pulmonary hypertension in rats by inhibiting RhoA/Rho kinase pathway. METHODS: A total of 32 Westar rats was divided into 4 groups: normoxic controls (Group A), hypoxic controls (Group B), hypoxia plus atorvastatin [10 mg/(kg.d)] group(Group C), and hypoxia plus the vehicle of atorvastatin (Group D). Rats for hypoxia treatment were maintained under the condition of 10% FiO2 6 h/d for 4 weeks. At the end of 4 weeks, rats were anesthetized and the mean pulmonary arterial pressure (mPAP) was measured by right heart catheterization. The ratios of arteriole wall thickness to vascular external diameter (WT%), and vascular area to total vascular area (WA%) were measured by a computerized image analyzer. RhoA and phos-MYPT-1 expression in the pulmonary artery were determined by Western blot. RESULTS: Comparing with Group A, the mPAP [(29.6 ± 1.1)mmHg vs (16.8 ± 0.7)mmHg], RV/(LV+S) [(39.0 ± 0.7)%vs (29.4 ± 0.5)%], WT% [(35.6 ± 2.4)% vs (22.3 ± 1.2)%] and WA% [(56.5 ± 5.1)% vs (36.6 ± 2.3)%] in Group B were all significantly increased (P<0.05). Comparing with Group B, the mPAP [(25.3 ± 3.2)mmHg], RV/(LV+S) [(36.3 ± 2.1)%], WT%[(29.2 ± 3.2)%] and WA% [(48.1 ± 2.7)%] in Group C were significantly decreased. The vehicle of atorvastatin had no such effect. The expression of RhoA and phos-MYPT-1 in the pulmonary artery was increased in Group B, but it was decreased in Group C. CONCLUSION RhoA/Rho kinase pathway plays an important role in the development of hypoxic pulmonary hypertension. Atorvastatin can improve the symptoms of hypoxic pulmonary hypertension by inhibiting RhoA/Rho kinase activity.
Animals ; Anticholesteremic Agents ; pharmacology ; Atorvastatin ; Hemodynamics ; Heptanoic Acids ; pharmacology ; Hypertension, Pulmonary ; enzymology ; etiology ; physiopathology ; Hypoxia ; complications ; Male ; Pulmonary Artery ; enzymology ; Pyrroles ; pharmacology ; Random Allocation ; Rats ; Rats, Wistar ; Signal Transduction ; drug effects ; Ventricular Remodeling ; drug effects ; rho-Associated Kinases ; metabolism ; rhoA GTP-Binding Protein ; metabolism

Hypertension is associated with endothelial dysfunction and increased cardiovascular risk. Caveolin-1 regulates nitric oxide (NO) signaling by modulating endothelial nitric oxide synthase (eNOS). The purpose of this study was to examine whether HMG-CoA reductase inhibitor improves impaired endothelial function of the aorta in spontaneous hypertensive rat (SHR) and to determine the underlying mechanisms involved. Eight-week-old male SHR were assigned to either a control group (CON, n=11) or a rosuvastatin group (ROS, n=12), rosuvastatin (10 mg/kg/day) administered for eight weeks. Abdominal aortic rings were prepared and responses to acetylcholine (10-9-10-4 M) were determined in vitro. To evaluate the potential role of NO and caveolin-1, we examined the plasma activity of NOx, eNOS, phosphorylated-eNOS and expression of caveolin-1. The relaxation in response to acetylcholine was significantly enhanced in ROS compared to CON. Expression of eNOS RNA was unchanged, whereas NOx level and phosphorylated-eNOS at serine-1177 was increased accompanied with depressed level of caveolin-1 in ROS. We conclude that 3-Hydroxy-3-methylglutaryl Coenzyme-A (HMG-CoA) reductase inhibitor can improve impaired endothelial dysfunction in SHR, and its underlying mechanisms are associated with increased NO production. Furthermore, HMG-CoA reductase inhibitor can activate the eNOS by phosphorylation related to decreased caveolin-1 abundance. These results imply the therapeutic strategies for the high blood pressure-associated endothelial dysfunction through modifying caveolin status.
Acetylcholine/metabolism ; Animals ; Aorta/metabolism/physiopathology ; Blood Pressure/drug effects ; Caveolin 1/*metabolism ; Down-Regulation ; Drug Administration Schedule ; Endothelium, Vascular/*drug effects/physiopathology ; Fluorobenzenes/administration & dosage/*pharmacology ; Hydroxymethylglutaryl-CoA Reductase Inhibitors/administration & dosage/*pharmacology ; Hypertension/enzymology/metabolism/*physiopathology ; Male ; Nitric Oxide/blood ; Nitric Oxide Synthase Type III/*metabolism ; Phosphorylation ; Pyrimidines/administration & dosage/*pharmacology ; Rats ; Rats, Inbred SHR ; Sulfonamides/administration & dosage/*pharmacology ; Vasodilation/drug effects

The activation of protein kinase C (PKC) is not only a pivotal node during cardiac hypertrophy in chronic pressure-overloaded heart, but also involved in the regulation of cardiac contractility. The aim of this paper was to observe PKC modulation in cardiac contractility at different stages of cardiac hypertrophy in spontaneously hypertensive rat (SHR). The cardiomyocytes were isolated from 4- and 10-month-old normotensive Wistar-Kyoto (WKY) and SHR rat hearts. The shortening amplitude of unloading contraction in cardiomyocytes was observed by an Edge Detector system. The shortening amplitude in WKY rat cardiomyocytes increased gradually as the stimulating frequency increased from 1 to 3 Hz. The shortening amplitude was positively correlated with stimulating frequency. The shortening amplitude in 4-month-old SHR group was enhanced as compared with that in WKY group at the same stimulating frequency. When the stimulating frequency increased, the shortening amplitude did not increase in 4-month-old SHR group. There was no difference in shortening amplitude between 10-month-old SHR and WKY groups at 1-Hz stimulating frequency. But the shortening amplitude in 10-month-old SHR group decreased when the stimulating frequency increased to 3 Hz. The perfusion of 50, 100 or 200 nmol/L PMA (a non-specific agonist of PKCs) significantly reduced the shortening amplitude in WKY and SHR groups. The shortening amplitude was reduced to (69.8±1.9)%, (58.2±2.2)% and (22.7±2.5)% (all P<0.01), respectively, in WKY group, as compared with that in HEPES buffer perfusion (100%). It was reduced to (6.1±0.7)%, (2.4±0.2)% and (12.5±2.6)% (all P<0.01) in 4-month-old SHR group, and (65.7±1.6)%, (53.9±4.0)% and (16.3±2.0)% (all P<0.01) in 10-month-old SHR group. The decreases in shortening amplitude in 4-month-old SHR group were more significant than those in 10-month-old SHR and WKY groups. On the other hand, 200 nmol/L of staurosporine, an inhibitor of PKC, significantly increased the shortening amplitude of cardiomyocytes in WKY, 4-month-old SHR, and 10-month-old SHR groups by (63.63±4.53)%, (80.82±4.61)% and (80.97±4.59)%, respectively (all P<0.05). The results suggest that the PKC isoforms inducing negative inotropic effect may be activated at the early stage of cardiac hypertrophy in SHR rats, and are possibly involved in the modulation of cardiac contractility. The activated PKC isoforms return to their normal activity at the stable stage of cardiac hypertrophy in SHR rats.
Animals ; Cardiomegaly ; enzymology ; Heart ; physiopathology ; Hypertension ; physiopathology ; Myocardial Contraction ; Myocytes, Cardiac ; enzymology ; Protein Kinase C ; metabolism ; Rats ; Rats, Inbred SHR ; Rats, Inbred WKY