We studied the effect of propofol (PPF) on the endothelium-dependent vascular responses in isolated rat thoracic aorta. In aortic rings with endothelium, PPF inhibited the phenylephrine (PE)-induced contraction in a concentration-dependent manner. In PE-precontracted preparations, PPF attenuated the endothelium-dependent relaxation by acetylcholine but not by A23187. And PPF did not attenuate the endothelium-independent relaxation by sodium nitroprusside (SNP).

The therapeutic efficacy of xylamine in the field of psychological medicine has been recognized for years and the drug is used to treat depression and some other conditions, but little is known about its mechanism of action on vascular system. Therefore, the present study was designed to investigate the influence of xylamine on the contractile responses of isolated rat thoracic arteries to phenylephrine(PE) and potassium chloride(KCl). Xylamine produced a concentration-dependent relaxation in PE-precontracted endothelium intact(+E) rat aortic rings, but not in a KCl-precontracted aortic rings.

We studied the effects of trazodone on arterial blood pressure in anesthesized guinea pigs, and on vascular responses in isolated thoracic aorta. Trazodone produced a concentration-dependent relaxation in phenylephrine-precontracted endothelium intact (+E) rings, but not in a KCl-precontracted aortic rings. These relaxant effects of trazodone on +E rings were siginificantly greater than those on denuded (-E) rings. The trazodone-induced relaxation was suppressed by gilbenclamide and tetrabutylammonium, but not by N(G)-nitro-L-arginine (L-NNA), N(omega)-nitro-L-arginine methyl ester (L-NAME), methylene blue (MB), nifedipine, indomethacin, 2-nitro-4-carboxyphenyl-n,n-diphenylcarbamate (NCDC) and clotrimazole. In vivo, infusion of trazodone elicited a significant decrease in arterial blood pressure.

The vasorelaxant effect of serotonin reuptake inhibitor fluoxetine was investigated in rat isolated thoracic aorta. Fluoxetine induced a concentration-dependent relaxation in aorta precontracted with phenylephrine (PE) and KCl. These relaxations were suppressed by removal of the endothelium (-E) or pretreatment of nitric oxide synthase inhibitors, N(G)-nitro-L-arginine (L-NNA) and N(omega)-nitro-Larginine methyl ester (L-NAME), guanylate cyclase inhibitors, methylene blue (MB) and 1H-[1,2,4]oxadiazolo [4,3-a]quinoxalin-1-one (ODQ), and Ca²+ channel blockers, nifedipine and verapamil, in PE-precontracted +E rings.

The aim of this study was to establish selective hepatic artery catheterization technique through percutaneous femoral artery puncture and to offer digital subtraction angiography(DSA) of hepatic artery in beagle dogs. Percutaneous femoral artery puncture was performed with Sheldinger's method. Microferret TM- 18 Infusion catheter(William, Cook, Europe) was introduced into abdominal aorta. Then, under fluoroscopy, iopamidol 370(Bracco, Italy) was injected to identify celiac artery and `J' shpaed guide wire was introduced into celiac artery. Catheter could be introduced into celiac artery through guide wire. In this manner, catheter was located at the insertion of hepatic artery and DSA was performed. In DSA of beagle dogs, hepatic artery which was divided into lateral branch, right-medial branch, right-lateral branch of hepatic artery, cystic artery and gastroduodenal artery was opacified without superimposition of any other body structure and so was the parenchyme of liver afterward. In autopsy angiographic finding of resected liver, cystic artery, caudate branch, lateral branch, right-medial branch, right-lateral branch and quadrate branch of hepatic artery were identifed. It was concluded that selective hepatic artery catheterization technique was a minimally invasive method that facillitated the approach of hepatic artery and DSA was an excellent tool to visualize the vessle of liver in dogs.

Melatonin, the principal hormone of the vertebral pineal gland, participates in the regulation of cardiovascular system in vitro and in vivo. However, the effects of melatonin on vascular tissues are still vague. The aim of this study was to assess the relationship between phospholipase C (PLC) and nitric oxide synthase (NOS)/cyclic guanosine 3',5'-monophosphate (cGMP) signaling cascade in the relaxatory action of melatonin in isolated rat aorta. Melatonin induced a concentration-dependent relaxation in phenylephrine (PE)- and KCl-precontraceted endothelium intact (+E) aortic rings.

Melatonin, the principal hormone of the vertebral pineal gland, participates in the regulation of cardiovascular system in vitro and in vivo. Lithium inhibits both inositol polyphosphate phosphatase (IPPase) and inositol monophosphatase (IMPase), which are involved in a wide range of signal transduction pathways. The aim of the present study was to assess the effect of lithium on endothelial-dependent relaxation to melatonin and on the melatonin-induced inhibition of contraction by phenylephrine (PE) in isolated rat aorta. Melatonin induced a concentration-dependent relaxation in PE-precontracted in endothelium-intact (+E) aortic rings.