1.Effects of the novel compound pivanampeta on the fatty liver with hyperlipidemia in rabbits and quails
Chinese Pharmacological Bulletin 2003;0(12):-
AIM To investigate the effects of the novel compound pivanampeta on the fatty liver induced by cholesterol-feeding in rabbits and quails. METHODS ①24 male rabbits were divided into four groups randomly as following: control group, model group, pivanampet 1 and 5 mg?kg -1 groups. The serum levels of total cholesterol were determined after the rabbits were cholesterol-fed for 12 weeks. The morphological changes of liver were observed. The levels of cholesterol and malonal-dialdehyde and the activities of glutatione peroxidase in the homogenate of liver were also measured.②181 male quails were divided into six groups randomly:control group, model group, Simvastatin 5 mg?kg -1 group, pivanampet 3,6 and 9 mg?kg -1 groups. The serum levels of total cholesterol were determined after the quails had been fed with cholesterol diets for 11 weeks. After 14 weeks part of the animals were killed, the morphological changes of liver were observed. The hepatic coefficient were determined after the remaining quails were cholesterol-feeding for 18 weeks. RESULTS Pivanampet alleviated the liver Steatosis induced by cholesterol-feeding in rabbits and quals. It decreased total cholesterol levels, elevated the activity of glutatione peroxidase in the rabbits liver, and reversed the increasing hepatic coefficient in rabbits and quails. CONCLISION The novel compound Pivanampet can delay the formation of fatty liver by cholesterol-feeding.
2.Functional genomics in drug target research
Chinese Pharmacological Bulletin 1987;0(03):-
Due to the completion of human genome project and the advent of new technologies, the traditional drug discovery is shifting to genomics-based drug discovery. Target discovery is an important first step in drug discovery pipeline. In this review, we critically introduce the strategies and biology technologies for target discovery, especially focus on the likely impact of new technologies in drug target research and speculate the future trend of target research.
3.Effects of 1,3-dipropyl-8-cyclopentylxanthine,an adenosine A_1 receptor antagonist,on brain neuronal damage induced by hypoxia and reoxygenation
Medical Journal of Chinese People's Liberation Army 2001;0(07):-
Objective To observe the effects of 1,3-dipropyl-8-cyclopentylxanthine(DPCPX),an adenosine A1 receptor antagonist,on brain neurons damage induced by hypoxia and reoxygenation(H/R),and to elucidate the relevant mechanisms.Methods An in vitro cultured rat cerebral cortical neuronal H/R damage model was established;the effects of DPCPX were detected at final concentrations of 0(control),25,50,100nmol/L on the lactate dehydrogenase(LDH) release from normoxic neurons and H/R neurons which were treated with hypoxia for 8,12,24 hours followed by reoxygenation for 24 hours;the changes of malondialdehyde(MDA) content,activities of xanthine oxidase(XO) and Ca2+-ATPase in H/R neurons which were treated with hypoxia for 12 hours and reoxygenation for 24 hours brought by administration of DPCPX at the concentration of 100nmol/L were also determined by use of specific reagents.Results With addition of 100nmol/L DPCPX,the LDH release from H/R neurons which were treated with hypoxia for 12 hours and reoxygenation for 24 hours was significantly increased compared with that in control group(P
4.Preventive Effects of Iptakalim on Brain Edema Caused by Acute Hypobaric Hypoxia in Rats.
Space Medicine & Medical Engineering 2006;0(04):-
Objective To investigate the preventive effect of iptakalim hydrochloride(Ipt) on brain edema in rats after exposure to simulated high altitude and the mechanisms involved.Method Adult Wistar rats were randomly divided into normoxic control group,simulated plateau acute hypoxia group simulated 8 000 m for 8 h and three Ipt taking groups which were pretreated with 2, 4 and 8 mg(kg?d) of Ipt respectively for 7d before exposure to hypoxia.Water content was determined by the wet-dry method;Na~+,K~+,Ca~(2+) and Mg~(2+) content in the cortex was detected with all atomic absorption spectrophotometer;inorganic phosphorus standardization was applied to decide the activities of Na~+/K~+-ATPase,Ca~(2+)-ATPase and Mg~(2+)-ATPase;Occludin and AQP4 gene expression were determined by RT-PCR.Result The water content was increased and the concentration of Na~+ and Ca~(2+),the activities of Na~+/K~+-ATPase,Ca~(2+)-ATPase and Mg~(2+)-ATPase and the gene expression of the Occludin and AQP4 were all down-regulated in acute hypoxia group compared with normoxic control group.And these changes could be significantly relieved by pretreatment with Ipt.Conclusion Ipt can prevent the occurrence of brain edema caused by acute hypobaric hypoxia possibly related to the effect on water content,electrolytes concentration,ATPase activity and gene expressions of aquaporin and tight junction proteins.
5.Effects on gene expressions of G protein alpha subunits by activation of non-neuronal muscarinic receptor
Chinese Pharmacological Bulletin 1986;0(06):-
Aim To study the subtypes distribution of G-proteins and modulation by carbachol and pilocarpine on gene expression in endothelial cells.Methods The rat aorta endothelial cells were cultivated and incubated with carbachol and pilocarpine at the dose of 10~(-4) mol?L~(-1)for 6 h.Then the total RNA was extracted.The mRNA levels of G-protein ? subunits was measured by RT-PCR.Results Gq/11,Gs and Gi mRNA was detected in rat aorta endothelial cells,while G12/13 mRNA was not detected.Carbachol and pilocarpine treatment induced no changes in Gs,Gi and G11 mRNA.Gq mRNA was 72.7% up-regulated by carbachol and unchanged by pilocarpine.Conclusion In all G-protein ? subunits,only Gq mRNA was changed after activation of non-neuronal muscarinic receptor by carbachol.We can conclude that Gq-protein may play an important role in signal transduction of nonneuronal muscarinic receptor.
6.Tetrandrine ameliorates cirrhosis and portal hypertension by inhibiting nitric oxide in cirrhotic rats.
Journal of Huazhong University of Science and Technology (Medical Sciences) 2004;24(4):385-8, 395
To examine the role and effect of nitric oxide synthase type II (NOS II) in cirrhotic rats, expression of NOS II mRNA was detected by real time RT-PCR. The enzymatic activity of nitric oxide synthase and the circulating levels of NO, systemic and portal hemodynamics and quantification of cirrhosis were measured. Chinese traditional medicine was used to treat cirrhotic rats and the effect of NO was evaluated. Double-blind method was used in experiment. Our results showed the concentration of NO and the enzymatic activity of NOS increased markedly at all stages of cirrhosis and iNOSmRNA was strongly expressed. Meanwhile, the portal-venous-pressure (PVP) and portal-venous-flow (PVF) were significantly increased. NO, NOS and iNOSmRNA were positively correlated to the degree of hepatic fibrosis. Tetrandrine significantly inhibited NO production and the expression of iNOSmRNA. Our results suggested that increased hepatic expression of NOS II is one of the important factors causing cirrhosis and portal hypertension. Tetrandrine can significantly ameliorate cirrhosis and portal hypertension.
7.Regulatory effect of iptakalim hydrochloride on excess expression of adhesive molecules in endothelial cells injury with high concentration of D-glucose
Chinese Pharmacological Bulletin 2003;0(07):-
Aim To investigate the regulatory effects of Iptakalim hydrochloride(Ipt) on excess expression of monocyte chemoattractant protein-1(MCP-1), intercellular cell adhesive molecule type-1(ICAM-1),vascular cell adhesive molecule1-1(VCAM-1) mRNA in bovine aortic endothelial cells cultured with high concentration D-glucose.Methods The endothelial cells were divided into three groups: control,model and Ipt group.The MCP-1,ICAM-1 and VCAM-1 mRNA was detected by reverse transcription-polymerase chain reaction (RT-PCR).Results Compared with control group,MCP-1,ICAM-1 and VCAM-1 mRNA expres sion of model group all increased after treatments with 25 mmol?L~(-1) D-glucose for 16 h,respectively.Compare with model group,the excess expression of MCP-1,ICAM-1 mRNA was blocked by 1~10 ?mol?L~(-1) Ipt added for 20 h in advance,respectively but no significant effect was found in the expression of VCAM-1 mRNA.Conclusion High concentration of D-glucose induced excess expression of MCP-1,ICAM-1 and VCAM-1 mRNA,respectively.The excess expression of MCP-1,ICAM-1mRNA is inhibited by Ipt.
8.A new target for anti-ischemic drugs: mitochondrial ATP-sensitive potassium channel
Chinese Pharmacological Bulletin 1986;0(06):-
ATP sensitive potassium channels (K ATP ) have been thought to be a mediator of cardioprotection. Recent pharmacologic and molecular biology studies show the protective effects of K ATP openers are not dependent of action potential shortening and cardiodepressant effects, but mediated by preservation of mitochondrial function, which suggests a role for intracellular mitochondrial K ATP (mito K ATP ). The mechanism by opening mito K ATP produces cardioprotection is less clearer, however, it is thought that a beneficial effect may occur as the result of K + entry and intramitochondrial depolarization. This effect would reduce mitochondrial calcium overload and cause matrix swelling, which are shown to enhance ATP synthesis and stimulate mitochondrial respiration.
9.Potassium channels and the modulators in vascular smooth muscle cells
Yuge JIANG ; Hai WANG ;
Chinese Pharmacological Bulletin 1986;0(05):-
It is well documented that vascular tone is the key determinant of blood vessel resistance and blood flow. But vascular tone could be regulated by modulating the activity of potassium channel directly. Potassium channel openers promote vasodilation by inhibiting the activity of voltage dependent calcium channels and reducing Ca 2+ influx. In this case, inhibition results from membrane hyperpolarisation, which arises due to the stimulation of K + efflux through smooth muscle K + channels. While K + channels are blocked, vasoconstriction could be observed as a result of membrane depolarization, which opens voltage dependent calcium channels. The influx of Ca 2+ can promote smooth muscle contraction by making myosin light chain phosphorylation and arising thick myofilament and thin myofilament relative movements. In this article, the gene structure, current character, Pharmacological and physiological effects of the four subtypes potassium channels are reviewed.
10.The developments of vascular endothelial functions and cardiovascular disease factors
Dongmei CHEN ; Hai WANG ;
Chinese Pharmacological Bulletin 1986;0(04):-
The functions of vascular endothelial cells (VEC) are closely related with the etiology of cardiovascular diseases. The present paper reviews the bioactive substances secreted from endothelial cells and their regulatory effects on the tone of blood vessel wall, on the functions of platelet adhesion and aggregation, on the hemostatic and fibrinolytic systems.