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

The activity of Mg++-dependent, Ca++-activated adenosine triphosphatase (Ca-ATPase) of rat liver mitochondria was studied at varying medium compositions, pH and temperatures. The enzyme system was characteristically sensitive to Ca++ concentration with a KmCa of approximately 0.06 mM. The optimal concentration of Mg was about l mM, above which the enzyme activity was progressively inhibited. The inhibitory effect of high Mg++ concentrations appeared to be due to the alteration of the Mg++/ATP ratio. Variations in the Mg++/ATP ratio affected Vmax but not the KmATP. The pH optimum for enzyme activity increased as the incubation temperature decreased, but the optimal OH-/H+ ratio of the medium was constant at around 0.1, regardless of temperature. The activity of the enzyme was not affected by La# (0.01-1 mM) and Ruthenium red (2.5-10.0 microM). These results indicate that 1) the enzymatic characteristics of the Ca-ATPase system in the rat liver mitochondria is typical of those from other tissue preparations, 2) the enzyme system maintains the most effective catalytic conformation at a fixed level of OH-/H+ ratio of 0.1 when the temperature changes, and 3) the enzyme system may not play a role in the physiological transport of Ca++ in mitochondria.
Animal ; Ca(2+)-Transporting ATPase/metabolism* ; Calcium/pharmacology ; Enzyme Activation/drug effects ; Female ; Hydrogen-Ion Concentration ; Magnesium/pharmacology ; Male ; Mitochondria, Liver/enzymology* ; Rats ; Temperature

OBJECTIVETo explore the effects of paeoniflorin on antagonising the delayed neuronal death (DND) induced by cerebral ischemia,and the relation between DND, cerebral tissue energy metabolism, nitric oxide (NO) and nitric oxide synthase (NOS).

METHODIncomplete cerebral ischemia induced was induced by ligating bilateral arteries carotis communis for 20 min followed by reperfusion 48 h in rats. The indexes including Na(+)-K(+)-ATPase activity, lactic acid content, Ca(2+)-ATPase, Mg(2+)-ATPase activity, NO content and NOS activity were determined in fore brain cortex at 48 h after reperfusion.

RESULTNa(+)-K(+)-ATPase, Ca(2+)-ATPase and Mg(2+)-ATPase activity were lowered (P < 0.01), NO level was decreased (P < 0.01), NOS activity dropped (P < 0.01) in cerebral tissue at 48h after reperfusion, but lactic acid level had no change. Paeoniflorin could prevent reduction of Na(+)-K(+)-ATPase activity (P < 0.05, P < 0.01), increase NO level (P < 0.01), enhance NOS activity (P < 0.01) at 48h after reperfusion.

CONCLUSIONDND induced by ischemia may be concerned with energy metabolism disorder and decrease of NO formation. Paeoniflorin may play the role of antagonising cerebral ischemia by adjusting cerebral energy metabolism and nitric oxide formation.

Animals ; Benzoates ; isolation & purification ; pharmacology ; Brain ; metabolism ; Brain Ischemia ; complications ; Bridged-Ring Compounds ; isolation & purification ; pharmacology ; Ca(2+) Mg(2+)-ATPase ; metabolism ; Calcium-Transporting ATPases ; metabolism ; Energy Metabolism ; Female ; Gerbillinae ; Glucosides ; isolation & purification ; pharmacology ; Lactic Acid ; metabolism ; Male ; Monoterpenes ; Nitric Oxide ; metabolism ; Nitric Oxide Synthase ; metabolism ; Paeonia ; chemistry ; Plants, Medicinal ; chemistry ; Reperfusion Injury ; etiology ; metabolism ; Sodium-Potassium-Exchanging ATPase ; metabolism

OBJECTIVETo study the effects of methyl protodioscin on the [Ca2+]i and the ATPase activity in cardiomyocytes, as well as their mechanisms.

METHODThe cardiomyocytes were randomly divided into three groups, the control group treated with no serumal DMEM, the MPD group treated with MPD and the dilthiazem group treated with dilthiazem. Fluorospectrophotometer was used to determined the level of myocardial cell intracellular Ca2+ [Ca2+]i. In the experiment of ATPase activity on cellular membrane, the cardiomyocytes were randomly divided into two groups, the control group treated with no serumal DMEM, the MPD group treated with MPD. The activity of Na+-K+-ATPase,Ca2+-Mg2+-ATPase and Mg2+-ATP ATPase were determined. The quantitative analysis of SERCA2a mRNA expression was studied by RT-PCR that the groups and treatments in cardiomyocytes same as the experiment for ATPase activity assay.

RESULTUnder the quiescent condition, compared to the control group, the level of [Ca2+]i in cardiomyocytes of the MPD group and dilthiazem group was no different. After treatment with 40 mmol x L(-1) KCl, [Ca2+] was significantly lower in the MPD group and the dilthiazem group, and the intensity of peak value in time course of 60 s, the dilthiazem group and the MPD group also were lower than the control group (P < 0.001). Ca2+-Mg2+-ATPase and Na+-K+-ATPase in cultured rat were increased after treated with MPD compared to treatment with no serumal DMEM (P < 0.05, P < 0.01), but Mg2+-ATPase in these groups had no different. The expression of SERCA2a mRNA between the MPD group and the control group was no different. MPD could not up-regulated or down-regulated SERCA2a in endocytoplasmic reticulum.

CONCLUSIONMethyl protodioscin could block the volt dependent form calcium channel in cellular membrane, and up-regulate the function of sodium pump and calcium pump, so that it could remain low calcium in the internal environment in cardiomyocytes.

Animals ; Ca(2+) Mg(2+)-ATPase ; metabolism ; Calcium ; metabolism ; Calcium Channels ; drug effects ; Cell Membrane ; drug effects ; metabolism ; Cells, Cultured ; Diltiazem ; pharmacology ; Diosgenin ; analogs & derivatives ; pharmacology ; Enzyme Activation ; drug effects ; Female ; Male ; Myocytes, Cardiac ; drug effects ; metabolism ; Rats ; Rats, Sprague-Dawley ; Saponins ; pharmacology ; Sarcoplasmic Reticulum Calcium-Transporting ATPases ; metabolism ; Sodium-Potassium-Exchanging ATPase ; drug effects

This study is to investigate the authenticity between COLD and HOT natural attribute in the famous Chinese medicine formulas--Zuojinwan (Coptis-Evodia 6 : 1) and Fanzuojinwan (Coptis-Evodia 1 : 6) based on mice temperature tropism, and establish an objective method to estimate the difference of two natural attribute by using a cold/hot plate differentiating technology. The results indicated that the COLD nature Zuojinwan could decrease significantly the remaining rate of HOT-symptom rat on warm pad (P < 0.05). That was not notable to COLD-symptom rat. The interference result of COLD-HOT temperature tropism to COLD/HOT symptom rat in Fanzuojinwan was the reverse with the COLD nature Zuojinwan. Meanwhile, biochemical indicators which are relative to energy metabolism such as ATPase enzyme activity and total anti-oxidant capability (T-AOC), had corresponding change in the organism. In the study, the COLD and HOT natural tendency in Zuojinwan and Fanzuojinwan which were composed by the same herbs with different proportion could be expressed qualitatively, quantitatively, objectively and directly with applying animal temperature tropism, and be verified to philosophical idea of treating disease theory with "expelling heat with cold herbs and cryopathy requiring warm prescription", not "expelling heat with heat herbs and cryopathy requiring cold prescription" in ancient traditional Chinese medicine, which brings a new approach in investigation of the nature theory of traditional Chinese medicine.
Animals ; Antioxidants ; pharmacology ; Body Temperature ; Body Weight ; drug effects ; Ca(2+) Mg(2+)-ATPase ; metabolism ; Calcium-Transporting ATPases ; metabolism ; Cold Temperature ; Coptis ; chemistry ; Drugs, Chinese Herbal ; administration & dosage ; isolation & purification ; pharmacology ; Evodia ; chemistry ; Hot Temperature ; Liver ; enzymology ; Male ; Medicine, Chinese Traditional ; Mice ; Sodium-Potassium-Exchanging ATPase ; metabolism ; Tropism