I 2 Imidazoline binding sites have been shown to exist on cardiac myocytes of human beings and rat. Both of I 1 and I 2 imidazoline binding sites have been identified on vascular smooth muscle cells of various species. Vascular I 2 imidazoline binding sites may participate in vascular smooth muscle proliferation. The sympathetic nerves supplying the cardiovascular system are endowed with presynaptic inhibitory imidazoline receptors. Being different from most of the imidazolines, moxonidine does not activate presynaptic imidazoline receptors, but SR141716A, which is considered as a selective antagonist at cannabinoid receptors, antagonizes presynaptic imidazoline receptors. It has been shown that imidazolines exhibit antiarrhythmic action. Agamatine, which is endogenous ligand at imidazoline receptors, not only decreases the rate of pacemaker firing in sinoatrial node of animal, prolongs action potential duration on cardiac myocytes of human beings and animal, but also inhibits afterdepolarizations induced by isoproterenol. On the other hand, imidazolines and guanidines inhibit the cardiovascular K ATP channel in a noncompetitive manner, those effects might interfere with the cardioprotective effects of K ATP channel.

0.05). Phenylephrine induced contractile responses in a concentration-dependent manner in the dorsal detrusor strips, but not in the ventral detrusor strips. S-doxazosin, R-doxazosin and rac-doxazosin at 1 ?mol?L-1 antagonized the phenylephrine-induced contractile responses competitively in the dorsal detrusor strips, and their pKB values were 7.44?0.19, 7.39?0.14 and 7.38?0.30, respectively. Three pKB values of doxazosin and its enantiomers were not significantly different from each other. Electric field stimulation produced a steady contractile response that was completely inhibited by tetrodotoxin at 0.3 ?mol?L-1. S-doxazosin, R-doxazosin and rac-doxazosin significantly inhibited the contractile responses to electric field stimulation in the dorsal detrusor strips of the rabbit urinary bladder(P0.05). However, S-doxazosin, R-doxazosin and rac-doxazosin did not affect the responses to electric field stimulation in the ventral detrusor strips. Conclusion The pKB value of S-doxazosin against phenylephrine-induced contraction via-adrenoceptors is same to R-doxazosin and rac-doxazosin, and the three agents are able to inhibit the adrenergic contraction induced by electric field stimulation in dorsal detrusor strips of the rabbit urinary bladder.

AIM: To study the effects of urocortin(Ucn) on the isolated heart tissues of spontaneously hypertensive rat(SHR).METHODS: Effects of Ucn on contractile force and heart rate were observed in the SHR and Wistar rat right atrium,left atrium and right ventricle strip.RESULTS: Ucn(1-10 nmol/L) concentration-dependently increased the contractile force in the SHR and Wistar rat isolated right atrium.Ucn increased the contractile force in the SHR by(31.1?14.9)% at 3 nmol/L and by(65.7?22.4)% at 10 nmol/L,and its inotropic effect was significantly greater than that in Wistar rat(P

Objective To explore the factors related with difficulty of laparoscopic cholecystectomy(LC) for acute calculus cholecystitis.Methods A total of 245 patients were retrospectively divided into two groups:easy group(123patients)and difficult group(122patients,including 32patients of conversion to OC)based on surgery time and LC or OC.Results There were statistical differences between the groups in regards to preoperative body temperature,white blood cell count,surgical timing,the thickness of gallbladder wall,gallbladder volume,and diameter of common bile duct(all P

Objective To discuss the therapeutic effects of rhubarb and natrii sulfas for severe acute(pancreatitis)(SAP).Methods Eighty-three patietns with SAP were randomly divided into treatment group(group A,n=45) and control group(group B,n=38).The 2 groups received the same therapy except that group A received rhubarb and natrii sulfas through nasogastric tube.Results In treatment group(compared) to control group,the clinical symptoms such as abdominal pain and distention were more quickly(relieved),with early return to oral food intake,lesser complications and shorter hospital stay(all with P

Aim To study effects of intraduodenal administration of S-doxazosin, R-doxazosin and rac-doxazosin on the carotid blood pressure and urinary bladder function in anesthetized rats. Methods The various parameters of carotid blood pressure, heart rate, vesical micturition pressure, intercontraction interval in anesthetized rats were recorded with an ADInstruments PowerLab/8s data recording and analysis system, and the vesical micturition volume was measured simultaneously. Results S-Doxazosin, R-doxazosin and rac-doxazosin administered intraduodenally decreased the systolic blood pressure, diastolic blood pressure and mean arterial blood pressure significantly in anesthetized rats in a dose-dependent manner. The inhibition of mean arterial pressure by S-doxazosin, R-doxazosin and rac-doxazosin at 1.0 mg?kg-1 was 23.5%?4.6%, 38.5%?8.9% and 42.6%?7.5%, respectively. The ED30 values of decreasing mean arterial blood pressure by S-doxazosin, R-doxazosin and rac-doxazosin were (2.0?0.8),(0.6?0.7) and (0.6?0.5) mg?kg-1,respectively. S-Doxazosin had a weaker inhibitory effect on the carotid blood pressure compared with R-doxazosin and rac-doxazosin, but no significantly different effect was observed between R-doxazosin and rac-doxazosin on the carotid blood pressure. rac-Doxazosin produced a significant inhibition on the heart rate at the dosage from 0.1 mg?kg-1 to 3.0 mg?kg-1 in a dose-dependent manner, but S-doxazosin and R-doxazosin reduced the heart rate only at 3.0 mg?kg-1. S-Doxazosin, R-doxazosin and rac-doxazosin administered intraduodenally decreased the vesical micturition pressure dose-dependently in anesthetized rats. The maximal inhibition of vesical micturition pressure by S-doxazosin, R-doxazosin and rac-doxazosin was 13.4%?5.7%, 14.5%?11.0% and 10.9%?7.6%, and their inhibitory potency on the vesical micturition pressure was not significantly different each other. R-Doxazosin, however, decreased the intercontraction interval and vesical micturition volume significantly compared with S-doxazosin, but S-doxazosin and rac-doxazosin did not significantly affect the intercontraction interval and vesical micturition volume. Conclusion In comparison with R-doxazosin and rac-doxazosin, S-doxazosin administered intraduodenally remains the beneficial action on vesical micturition pressure and relieves the adverse effects on blood pressure, heart rate and intercontraction interval in anesthetized rats.

Aim To observe the modulation of adenosine triphosphate (ATP) on motility of isolated gastric smooth muscle from rat.Methods Longitudinal and circular muscle strips of rat gastric body and antrum were prepared, and the effects of ATP (0.1, 1,10,100 ?mol?L~-1 and 1 mmol?L~-1 ) on the motility of the strips were investigated. Results ATP induced a small relaxation followed by an obvious spasm in longi- tudinal muscle strips of the gastric body; when tone was raised by KCl, ATP induced a larger relaxation followed by a smaller spasm.ATP only produced contraction in circular muscle strips of the gastric body.Low concentration of ATP inhibited the contractile amplitude of the antral longitudinal strips, at the same time increased the frequency of the contraction apparently; when tone was raised by KCl, ATP produced a concentration-related relaxation.Low concentration of ATP firstly enhanced and then inhibited contractile amplitude of antral circular musle strips, while high concentration of ATP fully inhibited the motility. Conclusion We firstly reported the obvious effects of ATP on longitudinal and circular strips of rat gastric body and antrum. The effects of ATP on the four preparations were different from each other, suggesting that ATP plays an important modulatory role on motility of gastric smooth muscle of rats.

Ⅺ deficiency in Chinese Han population. Conclusion The 13 mutations of the F Ⅺ gene which were found in this study may unravel the molecular pathogenesis of the F Ⅺ deficiency in Chinese Han population.

Objective To explore the expression and clinical significance of phosphoenolpyruvate carboxykinase (PCK) and plaminogen activator inhibitor-1 (PAI-1) in pleomorphic adenoma and adjacent tumor tissues of parotid gland. Methods Immunohistoehemistry was used to detect the expression of PCK and PAI-1 in10 cases of normal parotid glands, 38 cases of pleomorphic adenoma (0 cm) , adjacent tumor tissues (0.5, 1.0, 1.5, 2.0 cm from the pleomorphic adenoma). Results PCK expressed in all cases of normal parotid glands and adjacent tumor tissues, while PAI-1 expressed in 4 cases of normal parotid glands. Except 18 samples of 2.0 cm apart from pleomorphic adenoma, PAI-1 was expressed in the other adjacent tumor tissues. There was no obvious difference of PCK expression among normal, pleomorphic adenoma and adjacent tumor tissues of parotid glands (P> 0.05). The difference of PAI-1 expression was detected between pleomorphic adenoma (0 cm) and normal parotid glands and adjacent tumor tissues (2.0 cm from the tumor, P < 0.05). Conclusion During the development of pleomorphic adenoma, the expression level of PAI-1 is progressively increased while no change of PCK expression is found. It is rather remarkable that translocation of PAI-1 and PCK expression from cytoplasm and plasma membrane to nucleus occurs. The results mentioned above suggest that PCK and PAI-1 might play important roles in the progress of pleomorphic adenoma.

Objective To investigate the expression of mitochondrial autophagy-associated protein PINK1 and Parkin in parotid pleomorphic adenoma (PA) and carcinoma ex pleomorphic adenoma(CA-EX-PA). Methods The expression of PINK1 and Parkin were detected by immunohistochemistry in 24 cases of normal parotid gland tissues, 32 cases of PA tissues and 42 cases of CA-EX-PA tissues. The correlations of PINK1 and Parkin expression with the clinicopathologic characteristics of CA-EX-PA patients were analyzed. Results The positive rates of PINK1 in normal parotid gland, PA and CA-EX-PA tissues were 100%, 91% and 67% respectively; and those of Parkin were 100%, 88% and 52% respectively. The expression rates of PINK1 and Parkin in PA and CA-EX-PA tissues were significantly lower than those in normal tissues (P < 0.05). The expression of PINK1 and Parkin protein were positively correlated in CA-EX-PA tissues (r=0.877, P < 0.01). In CA-EX-PA tissues, the expression of PINK1 and Parkin were associated with tumor invasion, lymph node metastasis and TNM stage (P < 0.05). Conclusion The expression of PINK1 and Parkin are decreased in PA and CA-EX-PA tissues. The decrease of mitochondrial autophagy activity might play important roles in the development, invasion and metastasis of parotid gland tumors.