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.

Antiviral Agents ; therapeutic use ; Hepatitis B, Chronic ; drug therapy ; Humans

Humans ; Neurotoxicity Syndromes ; etiology ; Xylenes ; toxicity

Medicine, Chinese Traditional ; Translations

Amino Acid Metabolism, Inborn Errors ; Humans ; Mitochondrial Diseases ; Sarcosine Dehydrogenase ; deficiency

Objective To explore the clinical efficacy and safety of low dose fentanyl combined to ropivacaine in subarachnoid block for cesarean section.Methods Eighty patients with ASA physical status Ⅰ and Ⅱscheduled to undergo cesarean section for delivery were randomly allocated to receiving spinally mixture none fentanyl ( group R),5 μg fentanyl ( group F5 ), 10 μg fentanyl ( group F10 ), and 15μg fentanyl ( group F15 ), combined with 1%ropivacaine 1 ml and 10% glucose 1 ml respectively,after combined spinal-epidural anesthesia puncture was applied at the L2～3 interspace.Heart rate, blood pressure, the onset and recovery time of the sensory and motor block,time to the highest level and the highest level of sensory block, time to the maximal extent and the maximal extent of the motor block were recorded at regular intervals.The adverse effects were sought during and after surgery.Neonatal outcome was assessed using Apgar score.Results The recovery of sensory block was prolonged significantly in group F10 and group F15 than in group R and group F5.Conclusion Ropivacaine with 10μg fentanyl is safe and effective in subarachnoid block for cesarean section.

Objective To estimate whether a change in the polarity of low atrial electrograms recorded near the ablation line is an accurate indicator of complete isthmus block in the radiofrequency ablation of typical atrial flutter. Methods Radiofrequency ablation was performed in 10 patients with typical atrial flutter. Electrograms were recorded around the tricuspid annulus using a duodecapolar halo catheter and the distal electrode of halo catheter positioned just near the ablation line. The electrogram polarity of the distal electrode pair (H potential) was analyzed during atrial flutter and during coronary sinus pacing before and after ablation. Results Radiofrequency ablation was performed during coronary sinus pacing in 8 patients and performed during atrial flutter in 2 patients. Complete isthmus block was achieved in all patients. Before ablation, the initial polarity of H potential was predominantly positive during coronary sinus pacing and predominantly negative during atrial flutter. After complete isthmus block was achieved, the initial polarity of H potential was predominantly negative during coronary sinus pacing in all the patients. Conclusion The change of the electrogram polarity recorded just near the ablation line during coronary sinus pacing after ablation of typical atrial flutter is a simple, quick and accurate indicator of complete isthmus block.

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.

Objective To investigate the effect of Qi-boosting & Yin-nourishing formula and purslane herb on expression of nitric oxide synthase (NOS) positive neuron in hippocampal CA1 area of diabetic rats. Methods The diabetic rat models were induced by intraperitoneal injection of streptozotocin. After prevented and treated with Qi-boosting & Yin-nourishing formula and purslane herb one month, the diabetic rats were killed, the expression of NOS was detected by NADPH-diaphorase histochemistry. Results The expression of NOS positive neuron in hippocampal CA1 area of diabetic rats which were prevented and treated with Qi-boosting & Yin-nourishing formula and purslane herb was increased (P

Integrative Medicine ; Medicine, Chinese Traditional