Ca(2+) Mg(2+)-ATPase ; genetics ; Genetic Therapy ; Heart Failure ; therapy

Animals ; Ca(2+) Mg(2+)-ATPase ; metabolism ; Ischemic Preconditioning, Myocardial ; Male ; Rats ; Rats, Sprague-Dawley ; Superoxide Dismutase ; metabolism

OBJECTIVETo explore the mechanism of cytotoxic effect of 2, 5-hexanedione (2, 5-HD) on motor neuron.

METHODSVsc4.1 (a cell line from motor neuron) was incubated with a series concentration of 2, 5-HD. The cell viability, Ca(2+) Mg(2+) ATPase and Na(+)K(+) ATPase were detected. Laser scanning confocal microscope (LSCM) was used for detecting intracellular calcium level. The average calcium level in VSC4.1 was measured by flow cytometry.

RESULTSThe cell viability was decreased when Vsc4.1 cells were treated with 2, 5-HD at the dosage of 2.5, 5.0, 7.5, 10, 15 and 20 mmol/L for 24 hours. Compared with the control group the activity of Ca(2+) Mg(2+) ATPase was decreased to 70.02%, 77.44% and 47.47% respectively; the activity of Na(+)K(+) ATPase was decreased to 82.07%, 72.45% and 50.71%. The difference was significant. Intracellular free calcium of VSC4.1 cell was increased rapidly within 10 s and then recovered within 40 seconds when it was exposed to 33.5 mmol/L 2, 5-HD. An increase in intracellular calcium was observed when the VSC4.1 was treated with 33.5 mmol/L 2, 5-HD. The peak of intracellular calcium level occurred ten minutes later.

CONCLUSIONThe disturbance of calcium homeostasis may be involved in the mechanisms of neurotoxicity of 2, 5-HD.

Animals ; Ca(2+) Mg(2+)-ATPase ; metabolism ; Calcium ; metabolism ; Cell Line ; Dose-Response Relationship, Drug ; Hexanones ; toxicity ; Motor Neurons ; drug effects ; metabolism ; Rats ; Sodium-Potassium-Exchanging ATPase ; metabolism

OBJECTIVETo explore the effects of low temperature on the functions of learning and memory and activities of ATPase in brain tissue of mice.

METHODS120 mice were randomly divided into 3 groups of A, B, and C with different cold exposure time. After low temperature test, learning and memory ability and activities of ATPase in brain tissue of the mice were measured.

RESULTSCompared with corresponding control group, in the test of learning ability, the total electric shock period [(41.00 +/- 12.06), (45.90 +/- 13.61) min], the total electric times (85.00 +/- 15.81, 89.00 +/- 17.29), and the error reaction times (33.60 +/- 10.69, 39.00 +/- 11.63) were increased in group A and group C significantly (P < 0.01, P < 0.05), but the rate of right reaction (53.60% +/- 11.23%, 54.59% +/- 6.14%) were decreased in group A and group C significantly (P < 0.01, P < 0.05). In the test of memory ability, the total electric shock period [(19.00 +/- 4.62), (51.70 +/- 15.19) min] in group A and group C were increased significantly (P < 0.05, P < 0.01), the rate of right reaction (86.17% +/- 6.34%, 65.92% +/- 8.17%) in group A and group C were decreased significantly (P < 0.05). In test of activities of ATPase in brain tissue, the activities of Na(+)-K(+)-ATPase and activities of Ca(2+)-Mg(2+)-ATPase in brain tissue in group A and group C were decreased significantly (P < 0.05, P < 0.01).

CONCLUSIONLow temperature could decrease the functions of learning and memory and the activities of Na+-K+-ATPase and Ca(2+)-Mg(2+)-ATPase in brain tissue of mice.

Animals ; Brain ; enzymology ; Ca(2+) Mg(2+)-ATPase ; metabolism ; Cold Temperature ; adverse effects ; Environmental Exposure ; adverse effects ; Female ; Male ; Maze Learning ; Memory ; Mice ; Sodium-Potassium-Exchanging ATPase ; metabolism

OBJECTIVETo investigate the effects of polybrominated diphenyl ether-153 (BDE-153) exposure during lactation period on the calcium ion (Ca(2+)) concentration and calcium-activated enzyme levels in cerebral cortical cells among adult rats and to provide a scientific basis for the study on the developmental neurotoxicity of BDE-153.

METHODSForty newborn male rats were randomly and equally divided into four groups according to their body weights and litters: 1, 5, and 10 mg/kg BDE-153 groups and olive oil solvent control group. On postnatal day 10 (PND 10), the BDE-153 groups were administrated BDE-153 (0.1 ml/10 g body weight) by intraperitoneal injection, while the olive oil solvent control group was given an equal volume of olive oil. Two months later, these rats were decapitated, and the cerebral cortex was separated quickly on an ice-cold dish. The Ca(2+) concentration in cerebral cortical cells was measured by flow cytometry. The activities of calcineurin (CaN) and Ca(2+)-Mg(2+)-ATP enzyme were determined by colorimetric method. The mRNA and protein expression of calpain-1 and calpain-2 was measured by real-time quantitative PCR and Western blot.

RESULTSThe mean fluorescence intensities of intracellular Ca(2+) in control group and 1, 5, and 10 mg/kg BDE-153 groups were 10.83, 1.48, 1.93, and 0.62, respectively; the 1, 5, and 10 mg/kg BDE-153 groups had significantly lower intercellular Ca(2+) concentrations than the control group (P < 0.05). The activities of CaN and Ca(2+)-Mg(2+)-ATP enzyme and mRNA and protein expression of calpain-1 showed no significant differences between the 1, 5, and 10 mg/kg BDE-153 groups and control group (P > 0.05). The protein expression of calpain-2 increased as the dose of BDE-153 rose. Compared with the control group (mRNA: 0.81±0.26; protein: 0.15±0.07), the 5 and 10 mg/kg BDE-153 groups had significantly higher mRNA expression of calpain-2 (5 mg/kg BDE-153 group: 1.16±0.52; 10 mg/kg BDE-153 group: 1.32±0.23) and significantly higher protein expression of calpain-2 (5 mg/kg BDE-153 group: 0.31±0.07; 10 mg/kg BDE-153 group: 0.37±0.06) (P < 0.05). The 10 mg/kg BDE-153 group had significantly higher protein expression of calpain-2 than the 1 mg/kg BDE-153 group (0.37±0.06 vs 0.22±0.07, P < 0.05).

CONCLUSIONCa(2+-) mediated calpain-2 activation may be one of the main mechanisms of BDE-153 neurotoxicity.

Animals ; Animals, Newborn ; Ca(2+) Mg(2+)-ATPase ; metabolism ; Calcineurin ; metabolism ; Calcium ; metabolism ; Calpain ; metabolism ; Cerebral Cortex ; metabolism ; Male ; Polybrominated Biphenyls ; toxicity ; Rats ; Rats, Sprague-Dawley

OBJECTIVETo evaluate the effect of stretch on sarco(endo)plasmic reticulum Ca2+-Mg2+ ATPases activity and mRNA level and study the remodeling reaction of muscle in a variety of mechanical environments.

METHODSMyoblast from maxillofacial skeletal muscle of one-week-old male Sprague-Dawley rat was cultured and stretched cyclicly using a four-point bend device. Inorganic Phosphorus test was used to compare the activity of Ca2+-Mg2+ ATPases of myoblast before and after stretch. RT-PCR was also used to observe the Ca2+-Mg2+ ATPases mRNA level.

RESULTSThe activity of Ca2+-Mg2+ ATPases of myoblast down regulated significantly in 4 hours. During the period of 8 hours to 24 hours, up-regulation followed then returned to control level at the 48 hour point. RT-PCR showed that Ca2+-Mg2+ ATPases mRNA level were elevated by stretch, particularly at 2 hour and 48 hour point.

CONCLUSIONThe results suggested a transcriptional control of Ca2+-Mg2+ ATPases activity was involved in the muscle remodeling process induced by stretch.

Animals ; Ca(2+) Mg(2+)-ATPase ; metabolism ; Cells, Cultured ; Gene Expression Regulation ; Male ; Myoblasts ; enzymology ; Rats ; Rats, Sprague-Dawley ; Sarcoplasmic Reticulum ; enzymology

OBJECTIVETo investigate the activity and expression of Ca(2+)-Mg(2+)-ATPase in irradiated rat masseter muscle.

METHODSThe rats were irradiated locally with a single dose of 20 Gy X-ray. The activities of Ca(2+)-Mg(2+)-ATPase were measured with colorimetric method. The protein expression of Ca(2+)-Mg(2+)-ATPase was determined by Western blotting and immunohistochemistry.

RESULTSThe activities of Ca(2+)-Mg(2+)-ATPase in masseter muscle decreased by approximately 20% and 40% in irradiated rats on days 3 and 30 postirradiation. There was significant difference in the expression of Ca(2+)-Mg(2+)-ATPase protein between irradiated and nonirradiated rats on day 30 postirradiation. Ca(2+)-Mg(2+)-ATPase protein was found in the cytoplasm of masseter muscle.

CONCLUSIONSThe decrease of ATPase activity played an important role in the cause of radiation-induced skeletal muscle injury, while there was no significant reduction in the expression of Ca(2+)-Mg(2+)-ATPase protein in irradiated rat masseter muscle.

Animals ; Blotting, Western ; Ca(2+) Mg(2+)-ATPase ; metabolism ; Cytoplasm ; enzymology ; Immunohistochemistry ; Masseter Muscle ; enzymology ; radiation effects ; Radiation Injuries, Experimental ; enzymology ; Rats

OBJECTIVE: To investigate the effect of benzo(α)pyrene on the ATPase activity and content of Ca²⁺ in the hippocampus of neonatal SD rats. METHODS: Sixty male and 60 female 4-days-old neonatal SD rats were randomly divided into 5 groups (n=24): a blank control group, a vehicle control group (peanut oil), 3 benzo(α)pyrene groups (0.02, 0.2 and 2 mg/kg, respectively). SD rats were given benzo(α)pyrene (dissolved in peanut oil) by gavage daily from postnatal day 4 (PND4) to PND20. The nerve reflex, the condition of neuro-muscle development and motion function were examined in the period of treatment. The colorimetric technique was used to detect the activity of Ca²⁺-ATPase and Ca²⁺-Mg²⁺-ATPase in hippocampus after the treatment. The concentration of Ca²⁺ of synapse in the hippocampus of rats was detected by fluorescent labeling. RESULTS: The results from the behavior tests showed that duration of surface reflex latency in rats with medium dose of benzo(α)pyrene was longer compared with that in the control group in PND12. The duration of surface reflex latency in rats with high dose of benzo(α) pyrene is longer in PND 14 and PND 16 compared with that in the control group (P<0.05). Compared with the rats in the control group, the activities of Ca²⁺-Mg²⁺-ATPase and Ca²⁺-ATPase in hippocampus in rats with high dose benzo(α) pyrene were significantly decreased, and the degree in the decrease of Ca²⁺-ATPase activity was dose-dependent (P<0.05). The contents of Ca²⁺ in the hippocampus in rats with medium or high dose of benzo(α) pyrene were significantly increased compared with that in the control group (P<0.05), which showed a dose-dependent manner (P<0.05). CONCLUSION Benzo(α)pyrene exposure led to the decrease in ATPase activity as well as Ca²⁺ overload of the synapse in the hippocampal tissue, which in turn results in the nerve damage of newborn SD rats.
Animals ; Benzo(a)pyrene ; toxicity ; Ca(2+) Mg(2+)-ATPase ; metabolism ; Calcium ; metabolism ; Calcium-Transporting ATPases ; metabolism ; Female ; Hippocampus ; enzymology ; Male ; Rats ; Rats, Sprague-Dawley

AIMTo study the influence of crocetin on cardiac hypertrophy induced by overloading pressure in rats.

METHODSThe model of cardiac hypertrophy was produced by overloading pressure in rats. The animals were divided into five groups: sham-operation group (0.5% CMC-Na, ig), model group (operation + 0.5% CMC-Na, ig), captopril group (operation + 50 mg x kg(-1), ig), crocetin I (100 mg x kg(-1), ig) and crocetin II (50 mg x kg(-1), ig). All animals were treated for 30 d by ig. Then, cardiac indexes were examined. The activity of ATPase and the hydroxyproline content in heart were assayed by colorimetric analysis. Matrix metalloproteinases (MMPs) activity was assayed by SDS-PAGE zymography.

RESULTSCompared with the model group, crocetin was found to significantly reduce the cardiac indexes and the content of hydroxyproline in heart, increase the activity of Na+ , K+ -ATPase, Ca2+, Mg2+ -ATPase and inhibit MMPs activity.

CONCLUSIONThe activity of MMPs may play a key role in the cardiac hypertrophy induced by overloading pressure, and proprably as a result of decreasing the activity of MMPs. Crocetin was shown to prevent remodeling of cardiac hypertrophy induced by overloading pressure.

Animals ; Ca(2+) Mg(2+)-ATPase ; metabolism ; Cardiomegaly ; enzymology ; metabolism ; Carotenoids ; pharmacology ; Hydroxyproline ; metabolism ; Male ; Matrix Metalloproteinase 2 ; metabolism ; Matrix Metalloproteinase 9 ; metabolism ; Myocardium ; enzymology ; Organ Size ; drug effects ; Rats ; Rats, Sprague-Dawley ; Sodium-Potassium-Exchanging ATPase ; metabolism

OBJECTIVETo investigate the effects of benzo[a]pyrene (B[a]P) exposure on the behaviors and hippocampal oxidative stress and ATPase in rats and the molecular mechanism of neurobehavioral toxicity of B[a]P.

METHODSA total of 120 male SD rats (21 days old) were randomly and equally assigned to five groups: blank control group, vegetable oil (solvent control) group, and 2.5, 5, and 10 mg/kg B[a]P exposure groups. The rats in B[a]P exposure groups were injected intraperitoneally with B[a]P once a day for 4 consecutive weeks. Then, Morris water maze and shuttle box were used to evaluate the learning and memory abilities of rats; colorimetric assay was used to measure the activities of superoxide dismutase (SOD), Na(+)/K(+)-ATPase, and Ca(2+)/Mg(2+)-ATPase and the content of malonaldehyde (MDA) in the hippocampus; the concentration of Ca(2+) in the hippocampus was measured by fluorescent labeling.

RESULTSCompared with the blank control group and solvent control group, the B[a]P exposure groups exhibited significant increases in escape latency, active avoidance response latency, and passive avoidance response latency and significant decreases in number of platform crossings and active avoidance response frequency in the last test (P < 0.05 for all comparisons), with a dose-effect relationship. In addition, the B[a]P exposure groups had significantly lower activities of SOD, Na(+)/K(+)-AT-Pase, and Ca(2+)/Mg(2+)-ATPase and significantly higher MDA level and Ca(2+) concentration than the blank control group and solvent control group (P < 0.05 for all comparisons), with a dose-effect relationship.

CONCLUSIONThe neurobehavioral toxicity of B[a]P may be related to increased oxidative stress and decreased activities of Na(+)/K(+)-ATPase and Ca(2+)/Mg(2+)-ATPase in the hippocampus of rats.

Animals ; Benzo(a)pyrene ; toxicity ; Ca(2+) Mg(2+)-ATPase ; metabolism ; Hippocampus ; drug effects ; metabolism ; Male ; Oxidative Stress ; drug effects ; Rats ; Rats, Sprague-Dawley ; Sodium-Potassium-Exchanging ATPase ; metabolism ; Superoxide Dismutase ; metabolism