Objective:To assess the effect of angiotensin II type 1(AT1)receptor antagonist losartan on myocardium con- nexin43(Cx43)gap junction(GJ)expression in spontaneously hypertensive rats(SHRs)and investigate possible mech...Objective:To assess the effect of angiotensin II type 1(AT1)receptor antagonist losartan on myocardium con- nexin43(Cx43)gap junction(GJ)expression in spontaneously hypertensive rats(SHRs)and investigate possible mechanisms. Methods:Sixteen 9-week-old male SHRs and 8 age-matched male Wistar-Kyoto(WKY)rats were included in this study.SHRs were randomly divided into two groups to receive losartan at 30 mg/(kg·d)by oral gavage once daily for 8 weeks(SHR-L)or vehicle(0.9%saline)to act as controls(SHR-V);WKY rats receiving vehicle for 8 weeks served as normotensive controls.At the end of the experiment,rats were sacrificed and the hearts were removed.Expressions of Cx43 and nuclear factor-kappaB p65 (NF-κB p65)proteins in all three groups were observed and further investigations on the effect of angiotensin II type 1 receptor antagonist losartan(30 mg/(kg·d),8 weeks)on Cx43 expression were conducted with Western blot and immunohistochemistry. NF-κB p65 protein in nuclear extracts was determined by Western blot.Results:Left ventricular(LV)hypertrophy was prominent in SHRs,Cx43 and NF-κB p65 protein expressions were obviously upregulated and Cx43 distribution was dispersed over the cell surface.Treatment with losarton reduced the over-expressions of Cx43 and NF-κB p65 in LV myocardium.The distribution of Cx43 gap junction also became much regular and confined to intercalated disk after losartan treatment.Conclu- sion:Cx43 level was upregulated in LV myocardium of SHR during early stage of hypertrophy.Angiotensin II type 1 receptor antagonist losartan prevented Cx43 gap junction remodeling in hypertrophied left ventricles,possibly through the NF-κB pathway.展开更多
AIM:To determine the effect of pituitary adenylate cy-clase-activating polypeptide (PACAP) on left gastric artery (LGA) flow and to unveil the structural or functional important sites that may be critical for discrimi...AIM:To determine the effect of pituitary adenylate cy-clase-activating polypeptide (PACAP) on left gastric artery (LGA) flow and to unveil the structural or functional important sites that may be critical for discrimination of different receptor subtypes. METHODS: Peptides, including PACAP-27, PACAP-38, amino acid substituted PACAP-27 and C-terminus truncated analogues PACAP (27-38), were synthesized by a simultaneous multiple solid-phase peptide synthesizer. Flow probes of an ultrasound transit-time blood flowmeter were placed around the LGA of beagle dogs. Whenpeptides were infused intravenously, the blood flow was measured.RESULTS: [Ala4, Val5]-PACAP-27 caused a concentration-dependent vasodepressor action which was similar to that caused by PACAP-27. The LGA blood flow response to [Ala4, Val5]-PACAP-27 was significantly higher than that to PACAP-27, which was similar to that to vasoactive intestinal polypeptide (VIP) at the same dose. [Ala6]-PACAP-27 did not increase the peak LGA ? ow. [Gly8]-PACAP-27 showed a similar activity to VIP. [Asn24, Ser25, Ile26]-PACAP-27 did not change the activity of peptides at all doses. CONCLUSION: NH2 terminus is more important to biological activity of peptides and specifi c receptor recognition than COOH-terminus.展开更多
V_(1)导联P波终末电势(P-wave terminal force in V_(1),PtfV_(1))又称Morris指数,在心房颤动(简称房颤)相关脑卒中风险评估方面有着举足轻重的作用。PtfV_(1)与急性缺血性脑卒中、急性心肌梗死后的新发房颤、冠状动脉病变、心力衰竭、...V_(1)导联P波终末电势(P-wave terminal force in V_(1),PtfV_(1))又称Morris指数,在心房颤动(简称房颤)相关脑卒中风险评估方面有着举足轻重的作用。PtfV_(1)与急性缺血性脑卒中、急性心肌梗死后的新发房颤、冠状动脉病变、心力衰竭、左心室舒张功能障碍、睡眠呼吸障碍、急性精神压力、弥漫性大B细胞淋巴瘤等疾病的诊断和预后预测也有一定相关性。本文主要综述PtfV_(1)应用于多种临床疾病诊断及预后预测的最新研究进展。展开更多
文摘Objective:To assess the effect of angiotensin II type 1(AT1)receptor antagonist losartan on myocardium con- nexin43(Cx43)gap junction(GJ)expression in spontaneously hypertensive rats(SHRs)and investigate possible mechanisms. Methods:Sixteen 9-week-old male SHRs and 8 age-matched male Wistar-Kyoto(WKY)rats were included in this study.SHRs were randomly divided into two groups to receive losartan at 30 mg/(kg·d)by oral gavage once daily for 8 weeks(SHR-L)or vehicle(0.9%saline)to act as controls(SHR-V);WKY rats receiving vehicle for 8 weeks served as normotensive controls.At the end of the experiment,rats were sacrificed and the hearts were removed.Expressions of Cx43 and nuclear factor-kappaB p65 (NF-κB p65)proteins in all three groups were observed and further investigations on the effect of angiotensin II type 1 receptor antagonist losartan(30 mg/(kg·d),8 weeks)on Cx43 expression were conducted with Western blot and immunohistochemistry. NF-κB p65 protein in nuclear extracts was determined by Western blot.Results:Left ventricular(LV)hypertrophy was prominent in SHRs,Cx43 and NF-κB p65 protein expressions were obviously upregulated and Cx43 distribution was dispersed over the cell surface.Treatment with losarton reduced the over-expressions of Cx43 and NF-κB p65 in LV myocardium.The distribution of Cx43 gap junction also became much regular and confined to intercalated disk after losartan treatment.Conclu- sion:Cx43 level was upregulated in LV myocardium of SHR during early stage of hypertrophy.Angiotensin II type 1 receptor antagonist losartan prevented Cx43 gap junction remodeling in hypertrophied left ventricles,possibly through the NF-κB pathway.
基金Supported by (in part) Grants from Ministry of Education,Culture,Science,and Technology,Japan Society for the Promotion of Science and Special Fund of Six-Talented Peak of Jiangsu Province,No.07-B-15 (IB07)
文摘AIM:To determine the effect of pituitary adenylate cy-clase-activating polypeptide (PACAP) on left gastric artery (LGA) flow and to unveil the structural or functional important sites that may be critical for discrimination of different receptor subtypes. METHODS: Peptides, including PACAP-27, PACAP-38, amino acid substituted PACAP-27 and C-terminus truncated analogues PACAP (27-38), were synthesized by a simultaneous multiple solid-phase peptide synthesizer. Flow probes of an ultrasound transit-time blood flowmeter were placed around the LGA of beagle dogs. Whenpeptides were infused intravenously, the blood flow was measured.RESULTS: [Ala4, Val5]-PACAP-27 caused a concentration-dependent vasodepressor action which was similar to that caused by PACAP-27. The LGA blood flow response to [Ala4, Val5]-PACAP-27 was significantly higher than that to PACAP-27, which was similar to that to vasoactive intestinal polypeptide (VIP) at the same dose. [Ala6]-PACAP-27 did not increase the peak LGA ? ow. [Gly8]-PACAP-27 showed a similar activity to VIP. [Asn24, Ser25, Ile26]-PACAP-27 did not change the activity of peptides at all doses. CONCLUSION: NH2 terminus is more important to biological activity of peptides and specifi c receptor recognition than COOH-terminus.
文摘V_(1)导联P波终末电势(P-wave terminal force in V_(1),PtfV_(1))又称Morris指数,在心房颤动(简称房颤)相关脑卒中风险评估方面有着举足轻重的作用。PtfV_(1)与急性缺血性脑卒中、急性心肌梗死后的新发房颤、冠状动脉病变、心力衰竭、左心室舒张功能障碍、睡眠呼吸障碍、急性精神压力、弥漫性大B细胞淋巴瘤等疾病的诊断和预后预测也有一定相关性。本文主要综述PtfV_(1)应用于多种临床疾病诊断及预后预测的最新研究进展。
