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Objective To dynamically observe the effect of compound decotion on changes of Na+-K+-ATPase,Ca2+-ATPase activity,intracellular free Ca2+ contents and CaM expression jn bomogenate and mitochondria of rat brain tissues after traumatic brain injury(TBI)and investigate the molecular mechanism of neuroprotective effect of compound decotion.Methods Rat TBI models were made and divided into sham operation group,TBI group and compound decotion treatment group(treated with comof normal saline,twice per day for seven days.Rats were sacrificed at 24 h,72 h and 1 week after injury to dynamically observe activities of Na+-K+-ATPase and Ca2+-ATPase in bomogenate and mitochondria of rat brain tissues,concentration of free Ca2+ in neurocytes and expression change of CaM in brain tissues.Results The activities of Na+-K+-ATP ageand Ca2+-ATPase in homogenates and mitochondria of brain tissues markedly decreased at different time point and increased gradually after 72 hours in TBI group but wag still lower than that of sham operation group at one week after injury.However,compound decotion could significantly enhance the activities of Na+-K+-ATPageand Ca2+-ATPage(P＜0.05).In TBI group,concentration of free Ca2+ in neurocytes and CaM expression in brain tissues were elevated at different degrees at different time point and reached peak at 24 hours after injury but still lower than that of sham operation group at 72 hours.While concentration of free Ca2+ in neurocytes and CaM expression in brain tissues were significantly lower than those of TBI group at different time point(P＜0.05).Conclusions The neuroprotective effect of compound decotion may be related to its role in increasing activities of Na+-K+-ATPase and Ca2+-ATPase to facilitate cellular metabolism and decreasing concentration of free Ca2+ in neurocytes and CaM expression in brain tissues to mitigate secondary brain injury induced by Ca2+ over load.
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BACKGROUND AND OBJECTIVES: OSAS is thought to be due to an excessive loss of muscle tone in the upper airway or an abnormal reflex regulation of upper airway function during sleep. The aim of this study was to investigate the distribution of myosin heavy chain (MHC) isoforms of musculus uvulae in OSAS and snorers. Materials and Methods: Thirty seven patients included in the study underwent an uvulo-palato-pharyngoplasty (UPPP). All subjects had polysomnographic study before UPPP. ATPase stain at pH 9.4 were applied to muscle specimens obtained during UPPP. The numbers of MHC type I and II isoforms were counted. The patients were divided into three groups according to their repiratory disturbance index (RDI):mild (0-20), moderate (21-40), severe (>40). The differences in the distribution of muscle fiber types were compared between these groups. The correlation between the distribution of the fibers and the body mass index / age / RDI / minimum O2 saturation / duration of sleep apnea was investigated. RESULTS: The mean percentages standard deviation of type I fibers according to the severity of sleep apnea were as follows:22.5+/-3.2% in mild sleep apnea group (n=5), 19.8+/-2.3% in moderate sleep apnea group (n=1), 17.5+/-3.6% in severe sleep apnea group (n=1). There were statistically significant differences in the distribution of MHC type I and II isoforms between mild group and moderate and / or severe group (p.05). CONCLUSION: The proportion of MHC type I isoforms in musculus uvulae was decreased according to the severity and duration of sleep apnea (p<.01).
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Humans , Adenosine Triphosphatases , Body Mass Index , Hydrogen-Ion Concentration , Myosin Heavy Chains , Myosins , Protein Isoforms , Reflex, Abnormal , Sleep Apnea Syndromes , Sleep Apnea, Obstructive , Snoring , UvulaABSTRACT
Objective To investigate the possible roles of hemodynamics, circulating hormones, cell cation transport and cyclic nucleotides in left ventricular hypertrophy (LVH) of essential hypertension (EH) in vivo. Methods Blood pressure, total peripheral resistance (TPR) and plasma norepinephrine (NE), endothelin (ET), angiotensin Ⅱ (AngⅡ), endogenous digitalis like substances (EDLS) and atrial natriuretic peptide (ANP) were determined, along with the measurements of lymphocytic membrane ion pumps, cations and cyclic nucleotides in 45 EH patients with LVH (12 concentric hypertrophy, 33 eccentric hypertrophy), 30 normal subjects and 45 EH patients without LVH (as double concurrent controls). Multiple stepwise regression analysis was computed using left ventricular mass index (LVMI) as dependent variable and 22 parameters as independent variables. Results (1) In EH patients with LVH, increases were seen in systolic blood pressure, mean arterial pressure (MAP) and NE, ET, AngⅡ, EDLS and ANP as well as lymphocytic Na +, Ca 2+ , cAMP and cAMP/cGMP ratio, while Na + K + ATPase and Ca 2+ ATPase activities, K + and Mg 2+ decreased. (2) Five hormones were related respectively to ion pumps, Na +, Ca 2+ and cyclic nucleotides. (3) LVMI were correlated with NE, ET, AngⅡ and EDLS, Ca 2+ ATPase, Na +, cAMP and cAMP/cGMP ratio. (4) The regression equation revealed that NE, ET, Ca 2+ ATPase, Mg 2+ and cAMP were the independent factors affecting LVH. (5) TPR and AngⅡ were higher, K + was lower in concentric LVH than those in eccentric LVH. Conclusion The changes of hemodynamics, circulating hormones, cell cation transport and cyclic nucleotides, or their interaction may be involved in the pathogenesis of LVH in EH. NE, ET. Ca 2+ ATPase, Mg 2+ and cAMP seem to play more important parts in LVH . TPR , whereas AngⅡ and K + may relate to cocentric LVH.
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Objective To explore the changes in ionic pump functions of cardiomyocyte cell membrane and the effects of compound hyperosmotic saline solution. Method Ninety-six Wistar rats were randomized into two groups: hyperosmotic saline solution (HES, n=48) and 0.9% sodium chloride solution injection (NS, n=48). Hemorrhagic shock model was reproduced by a gradient volume-control phase exsanguination, combined with an adjustment phase, from femoral artery, with mean arterial pressure kept at 40kPa. At each time-point (pre-shock stage, shock, and 30min, 60min, 90min, 120min post-resuscitation), eight rats were used for various tests. The ATPase activity of cardiomyocyte cell membrane and the myocardial pathologic changes were investigated at different time points. Results Compared with shock stage, the ATPase activity of group HSH was significantly different (P
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Objective To study the expression of normal and variant ATP7B proteins, in order to further find the mechanism of Wilson disease. Methods Normal ATP7BcDNA/pcDNA3 was made and mutant variants Arg778Leu/pcDNA3, Gln914Ter/pcDNA3 and Thr935Met/pcDNA3 were constructed by using Quik-Change TM Site-directed Mutagenesis Kit in vitro. A good quality rabbit polyclonal antibody against the N-terminal functional domains of ATP7B was produced and purified, being named rabbit anti-human ATP7Bn33-629 polyclonal antibody. Normal and variant expression plasmids constructed above were transfected into Chinese hamster ovary (CHO) cells. After a 36-hour incubation at 37℃, the transfected CHO cells were collected. Expression of normal and variant ATP7B protein were detected and compared by Western blot analysis of cell lysates using ATP7Bn33-629 antibody. Results Expression of ATP7B normal protein in transfected CHO cells was the same as that of ATP7B variant proteins Arg778Leu and Thr935Met.Gln914Ter variant shortened ATP7B protein to 100 kd and increased the level of expression. Conclusion The mechanism under disorder of copper transport caused by the missense mutations should be not related to the level of expression. The increased level of expression caused by Gln914Ter might be associated with the shortened ATP7B protein that needs less time for translation.
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AIM: To study mechanism of hepatocytic mitochondria damage following septic shock. METHODS: 30 SD rats were randomly divided into three groups: sham operation group, 12 h cecal ligation and puncture (CLP) group and 16 h CLP group. The model of septic shock was made by cecal ligation and puncture. The liver mitochondria respiratory control rate (RCR), phosphate/oxygen (P/O) and ATPase activities were assayed. RESULTS: In 12 h CLP group mean artery pressure (MAP) [(9.54?1.26) kPa] was significantly lower than sham operation group [(14.58?1.32) kPa, P
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AIM: To explore the pathophysiological bases in the pathogenesis of the lasting emotional behavioral disorders following posttraumatic stress disorder (PTSD). METHODS: 240 male Wistar rats were divided randomly into 3 groups. Group SE ( n =96) for rats with PTSD-like behavior by constant pulsating current of 100 ?A with intratrain frequencies of 16 Hz, pulsating duration of 1 ms, train duration of 10 s and interstimulus interval of 7 min for 5 days with 8 times per day. Group CE ( n =96) for control with electrode implanted in hippocampus without stimulation, and Group NC ( n =48) for normal control. The activities of Na +-K +-ATPase and Ca 2+ -ATPase, levels of intracellular calcium and free calmodulin (CaM), and the total CaM expression were detected in hippocampi of experimental rats. RESULTS: The activities of Na +-K +-ATPase and Ca 2+ -ATPase in mitochondria of hippocampal cells in Group SE rats were significantly decreased at 48 h and 72 h after the last stimulation, respectively. The intracellular free calcium levels were increased, and the mean channel fluorescence of intracellular free CaM decreased remarkably at 72 h poststimulation, while the expression of total CaM was significantly elevated at 48 h after the last stimulation in hippocampi of Group SE rats. CONCLUSION: The lasting increased levels of intracellular free calcium and expression of Ca 2+ -CaM in hippocampus, as well as the dysfunction of Na +-K + pump and Ca 2+ -ATPase in mitochondria may play important roles in the long-term neuropsychological sequelae in PTSD.
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Objective To investigate the role of mitochondrial KATP channel in the mechanism of the protective effect of ischemic preconditioning (IP) against ischemia-reperfusion (I/R) injury.Methods Forty-eight Wistar rats of both sexs weighing 250-350 g were used in this study. Forty rats were randomly divided into 5 groups ( n = 8 each): group A I/R; group B IP+ I/R; group C diazoxide (DZ mito-KATP channel activator) + I/R; group D 5-HD (mito-KATP channel blocker) + IP + I/R and group E 5-HD + DZ + I/R. Another 8 animals were used for electron microscopic examination of normal mitochondria as control. The animals were anesthetized with intraperitoneal pentobarbital 30 mg?kg-1. The hearts were immediately excised and passively perfused in a Langendorff apparatus with K-H solution at 5.8 kPa perfusion pressure and 36.5-37.5℃ via aortic cannulation. A fluid-filled latex balloon was via left atrium in left ventricle for the measurement of left ventricular function. I/R was induced after 30 min stabilization by clamping aortic cannula for 40 min followed by 30 min reperfusion. In group B and D the isolated hearts underwent 2 episodes of 5 min ischemia followed by 5 min reperfusion before I/R. In group C and E DZ 50 ?mol?L-1 was infused for 10 min and in group D and E 5-HD 100 ?mol?L-1 was infused for 10 min before I/R. HR, LVSP, LVEDP and coronary flow (CF) were measured at the end of stabilization (T0 , baseline), immediately before I/R (T1 ) and at 10, 20 and 30 min of reperfusion (T2.3.4.), and left ventricular developed pressure (LVDP= LVSP- LVEDP) was calculated. Myocardial tissue was obtained at the end of 30 min reperfusion for electron microscopic examination of mitochondria. Mitochondrial ultrastructure was assessed by Flameng scoring system (0 = normal, 4 = severely damaged) .Results Ischemic and DZ preconditioning significantly increased LVDP and decreased LVEDP and Flameng score. 5-HD pretreatment partly antagonized the protective effect of IP and completely antagonized that of DZ against I/R injury. Conclusion Ischemic preconditioning protects the heart against I/R injury mainly by activating mitochondrial KATP channel.
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AIM: To study the effects of prearuptorin C (Pra-C) on myocardial sarcolemma Na~+, K~+-ATPase activity, myocardial mitochondria Na~+, K~+-ATPase, Ca~ 2+ -ATPase, Mg~ 2+ -ATPase activities and apperent Km and Vmax in spontaneously hypertensive (SHR) and renovascular hypertensive rats (RHR). METHODS: ATPase activity was measured with colourmetric method. Apparent Km and Vmax of both Na~+, K~+-ATPase in myocardial sarcolemma and Ca~ 2+ -ATPase in myocardial mitochondria were calculated according to Lineweaven-Burk double-reciprocal plot method with liner regression. RESULTS: The Vmax of both Na~+, K~+-ATPase in myocardial sarcolemma and Ca~ 2+ -ATPase in myocardial mitochondria were lower in SHR untreated group than that in SD control rats, while Km was higher than that in SD control rats. In RHRs untreated group, only Vmax was decreased, while the Km had no statistically change. Pra-C prevented the reduction of ATPase in amount, but not affected their intrinsic characteristics. CONCLUSIONS: The results suggest that both amounts and affinities to ATP of Na~+, K~+-ATPase and Ca~ 2+ -ATPase were decreased in SHRs, but in RHRs, only amounts of ATPase was decreased, while their affinities to ATP were unchanged. Treatment with Pra-C prevents the decrease in amount of ATPase.
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Objective To investigate the antifatigue effect of hyperoxia solution and its mechanism. Methods Eighty soldiers were randomly divided into two groups: hyperoxic solution group and common balance salt solution group The exercise selected was 5000 meters constantly running. The soldiers of each group were respectively given hyperoxic solution or balanced salt solution 250ml thirty minutes before running; then each were respectively given orally 150ml hyperoxia solution or balanced salt solution at 2000 meters and 4000 meters, The soldiers were bled before running and after running immediately, and the contents of lactic acid and malondialdehyde,the general ability of antioxidation and the energy of adenosine triphosphate enzyme were determined instantly. Results The contents of lactic acid and malondialdehyde of hyperoxic solution group were significantly less than that of control group ( P