ABSTRACT
OBJECTIVE@#To test the effect of Banxia Xiexin Decoction (, BXD) on the contraction and relaxation of gastric smooth muscle (SM) in diabetic gastroparesis (DGP) model rats, and to explore the mechanism of BXD in the prevention and treatment of DGP through experiments of signal pathway both in vivo and in vitro.@*METHODS@#Sixty Sprague-Dawley rats were divided into 6 groups according to a random number table: control group, model group, high-, medium- and low-dose BXD groups (9.2, 4.6 and 1.8 g/(kg·d), respectively), and domperidone group (10 mg/(kg·d)), 10 rats per group. DGP model was established initially by a single intraperitoneal injection of streptozotocin (STZ), and was confirmed by recording gastric emptying, intestinal transport velocity and gastric myoelectric activity of rats after 2 months. Each group was treated with a corresponding drug for 4 weeks. The mRNA and protein expressions of phospholipase C (PLC), inositol triphosphate (IP@*RESULTS@#Compared with the model group, high- and medium-dose BXD and domperidone significantly increased the expressions of PLC, IP@*CONCLUSIONS@#Treatment with high- and medium-dose BXD significantly attenuated STZ-induced experimental DGP in rats. The therapeutic effect of BXD on DGP rats might be associated with the PLC-IP
ABSTRACT
Objective To study the effects and the mechanism of the ethanol extract of Blueberry(BE) on relaxation vascular endothelium or smooth muscle.Methods To use rat aorta as the specimen,to observe the effects of BE on induced relaxation of the phenylephrine-precontracted aorta.and approach the mechanism on vascular endothelium or smooth muscle.Results BE induced relaxation of the phenylephrine-precontracted(1.0×10~(-5)mol·L~(-1) aorta in a dose-dependent way(P<0.01),which was disappeared by removal of functional endothelium(P<0.01).Pretreatment of the aortic tissues with NG-nitro-L-arginine methyl ester(L-NAME),methylene blue,or 1H[1,2,4]-oxadiazole-[4,3_a]-quinoxalin-1-one (ODQ) inhibited the vascular relaxation induced by BE(P<0.01).BE-induced vascular relaxations were also markedly attenuated by addition of verapamil or diltiazem,while the relaxant effect of BE was not blocked by pretreatment with indomethacine,glibenclamide,tetraethylammonium(TEA),atropine,propranolol(P<0.01).Conclusion These results suggest that BE dilates vascular smooth muscle via endothelium-dependent nitricoxide-cGMP signaling pathway,possible involvement of L-type Ca~(2+) channel.