Effects Of Valsartan On Ultrastructure In Rats With Portal Hypertensive Colopathy

Objective To observe the effects of valsartan, propranolol and two drugs combination to microcirculation of colonic mucous membrane and submucosa in rats with portal hypertensive colopathy(PHC), the changes of ultrastructure, protection to PHC of valsartan, propranolol and the combination.Methods Rat models of PHT were induced by composite factors, being randomly divided into model group, three treatment groups(valsartan group, propranolol group and two drups combined group ). In 42 days, treatment groups were respectively administered valsartan, propranolol and valsartan combined with propranolol. The dosage of valsartan was 20mg/kg, once a day, that of propranolol being 22.5mg/kg, twice everyday. Valsartan combined propranolol group was administered the same dosage by gavage. Normal control group and model control group were given the equal dose of tap water, once a day. The administration of each group continued fifteen days. Each group was measured portal vein pressure(PVP), mean arterial pressure(MAP). The serum levels of hyaluronic acid(HA) and precollagenâ…¢(PCâ…¢) were measured while colons were obtained in order to analyze the submucous vascellum areas, metrical diameters of phlebectasia under light microscope and to observe the ultrastructure by transmission electron microscope.Results Compared with model control group, valsartan, propranolol, and two drugs combination significantly decreased PVP respectively (p<0.01). The combined group more significantly reduced PVP than valsartan and propranolol group(p<0.05), and the difference wasn't significant between valsartan and propranolol group. Every treatment group didn't decrease MAP. The groups of valsartan and valsartan plus propranolol could decreaese the content of HA and PCâ…¢in blood serum (p<0.01 or p<0.05) when compared with model control group. Furthermore, groups of valsartan, propranolol and valsartan plus propranolol could cut down vascellum areas and metrical diameters of phlebectasia of submucosa (p<0.01). Especially, valsartan plus propranolol were the most effective group compared with others . Under the light microscope, model control group was observed with angiotelectasis of colonic mucous membrane, phlebectasia with big cavity and thin tubal wall as well, and a lot of lammatory cells infilrtation of colonic submucous. Medication groups weren't obviously shown angiotelectasis of colonic mucous membrane, while they were improved with phlebectasia and lammatory cells infilrtation of colonic submucous. Particularly, the combination group was most significant. By transmission electron microscope, model control group observed with microvilli of absorptive...