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OBJECTIVE@#To investigate the effect of electro-acupuncture (EA) on vasomotor symptoms in rats with acute cerebral infarction, by observing the changes in the expression of factors related to the phosphatidylinositol (PI) system.@*METHODS@#Forty-two Wistar rats were randomly divided into 3 groups by a random number table: the control group (n=6), the model group (n=18) and the EA group (n=18). The EA group was given EA treatment at Shuigou (GV 26) instantly after modeling with middle cerebral artery occlusion (MCAO) method, while the model and control groups were not given any treatment. The degrees of neurological deficiency were evaluated using neurological severity scores (NSS) and the brain blood flow was evaluated by a laser scanning confocal microscope. Western blot analysis was conducted to detect the expression levels of G-protein subtype (Gq) and calmodulin (CaM). Competition for protein binding was conducted to detect the expression level of inositol triphosphate (IP3). Thin layer quantitative analysis was conducted to detect the expression level of diacylglycerol (DAG). The expression level of intracellular concentration of free calcium ion ([Ca@*RESULTS@#The NSS of the model group was significantly higher than the control group at 3 and 6 h after MCAO (P<0.01), while the EA group was significantly lower than the model group at 6 h (P<0.01). The cerebral blood flow in the model group was significantly lower than the control group at 1, 3 and 6 h after MCAO (P<0.01), while for the EA group it was remarkably higher than the model group at the same time points (P<0.01). The expressions of Gq, CaM, IP3, DAG and [Ca@*CONCLUSION@#EA treatment at GV 26 can effectively decrease the over-expression of related factors of PI system in rats with acute cerebral infarction, improve cerebral autonomy movement, and alleviate cerebral vascular spasm.
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Animals , Rats , Acupuncture Therapy , Brain Ischemia , Cerebral Infarction/therapy , Electroacupuncture , Phosphatidylinositols , Rats, WistarABSTRACT
Backround: Aim of this study was to assess changes in vasomotion during post–occlusive reactive hyperaemia in patients after hyperbaric oxygen therapy (HBOT). Methods: 38 patients with type 2 diabetes mellitus underwent 15 sessions of HBOT consisting of 90 minutes of eathing 100 % oxygen at 2.5 atm. We used laser Doppler flowmetry (LDF) to assess vasomotion during post–occlusive reactive hyperaemia. Results: We observed significant increase in endothelial (3.22 [2.07 – 5.31] vs. 4.91 [2.9 – 6.57], p < 0.05), neurogenic (0.64 [0.44 – 1.01] vs. 0.85 [0.53 – 1.63], p < 0.05), cardiac (9.22 [7.21 – 13.79] vs. 12.74 [8.66 – 16.83], p < 0.05) and total spectral activity (20.93 [15.97 – 27.88] vs. 27.96 [17.45 – 37.99], p < 0.05) after HBOT. No significant changes were observed in myogenic and respiratory spectral activity Conclusion: Our study demonstrated vasomotion changes measured by LDF after HBOT.
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Objective To study the influence of high calcium ion environment on the membrane current of denervated aortic smooth muscles in iso-osmotic condition,as well as study the myogenic spontaneous vasomotion of the aortic smooth muscles under different pre-load state and intervention of calcium-channel blockers.Methods Smooth muscle samples were taken from the aortic smooth muscle layer of Kunming mice.The samples were fixed at two-ends in relaxed state and infiltrated in Ringer's solution.After stabilization,a glass microelectrode was adsorbed on the smooth muscle membrane to form gigaohm-seal.The current state of the membrane was observed under the physiological osmotic pressure.Then,the calcium ions concentration in the Ringer's solution was increased from 0.9 mol/L to 1.2 mol/L,and the immediate change of membrane current was observed after changing of osmotic pressure.Finally,the membrane potential change in iso-osmotic condition was observed when the pre-load was increased to 1 g,and the spontaneous vasomotion curves of the samples were recorded.Results In the relaxation state,the membrane current of the smooth muscle was increased significantly,i.e.(10.25±1.34) pA vs.(24.91±3.27) pA (P＜0.05),when the calcium ion concentration was increased from 0.9 mol/L to 1.2 mol/L in iso-osmotic condition.When the pre-load was increased,the variation amplitude of the membrane current was increased in iso-osmotic condition,i.e.(10.25±1.34) pA to (15.33±4.33) pA (P＜0.05) for the lower calcium ion concentration,and (24.91±3.27) pA to (33.31±7.25) pA (P＜0.05) for the higher calcium ion concentration.If only increasing the pre-load,the myogenic spontaneous vasomotion could be increased by 175％ for the condition of lower calcium ion concentration (0.9 mol/L).When the calcium ion concentration was increased to 1.2 mol/L,the spontaneous vasomotion frequency of the specimen was increased,and the range of the vasomotion could be further increased by 40％.After pretreatment with the calcium-channel blocker (0.5 g/L nitrendipine),the membrane current and myogenic spontaneous vasomotion were significantly decreased in the higher calcium ion environment,which indicated that the membrane potential and spontaneous vasomotion was dominated by calcium ions.Conclusions The increase of extracellular calcium ion concentration not only can improve the excitability of the aorta smooth muscle cells,but also can cause significant spontaneous vasomotion,and can improve the compliance of the smooth muscle tissue in pre-load variation.The calcium-channel blockers can inhibit calcium-dominated transmembrane currents,reduce myogenic spontaneous vasomotion,and enhance the stiffness of smooth muscle,which may have negative effects on windkessel vessel function.
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Objective: To determine the appropriate time of early administration of dopamine (DA) before nitroglycerin (GTN) for establishing rat model with vasomotor abnormalities. Methods: Rats were divided into 5 groups: normal group, DA Group and other 3 groups in accordance with DA at different time points (10, 30, 45 min) plus GTN .Common carotid artery (CCA) blood flow velocity was dynamically measured with pulsed Doppler flow probe to evaluate the influence of DA, GTN on blood flow velocity rate(BFVR). Results:The blood flow velocity rate induced by DA of All medication administration was different from the normal group within 10 minutes(P 0.05). The BFVR of 10min interval group had differences with the DA group at 45min, 50min, 55min, 60min, 65min and 70min(P 0.05). Conclusion: Subcutaneous injection of DA, 45m in after injection of GTN can induce vasomotor abnormalities in rat with phase characters. The model may be useful for vasoactive screening of anti-migraine drugs.
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Objective:The aim of this study was to observe the role of NO in the action of tetramethylpyrazine (TMP) on arterioles vasomotion induced by noradrenaline (NA), in order to make further understand of vasodilation mechanism of TMP.Methods: Albino rabbits weighting 2.0 ～ 2.5 kg were anesthetized. They were ventilated with room air via tracheotomy tube. The arterial pressure was monitored with a pressure transducer attached to a polyethylene canula in the right common carotid artery by four channel polygraph, the intestinal loop was mounted on the stage of an inverted microscope and bathed in balanced Kreb Ringer solution maintained at 37.5 ?C . The inside diameter of arterioles were measured manully on a TV monitor using a TV camera mounted on the microscope. Observe the changes of BP、 microcirculation and filtration of true capillary after injection of TMP 8mg/kg、 N G monomethyl L arginine( L NMMA) 10mg via a cannula in the left carotid artery after topical application of NA(0.8?g) conducted in the measured field. Results:TMP can inhibit spontaneous vasomotion in vasodilation; L NMMA can inhibit it in vasoconstriction stage. L NMMA have no effect on the action of TMP. Conclusions: Endogenous NO has no role in TMP's vasodilation.