Abstract— The effect of losartan on systolic blood pressure (SBP), function and structure of thoracic aorta and mesenteric artery was examined. Four-week-old Wistar rats, spontaneously hypertensive rats (SHR), and SHR treated with losartan (20 mg/kg/day for 5 weeks) were used. SBP was measured by the tail-cuff method weekly. Isometric contraction of aortal rings and neurogenic contractions of mesenteric artery were studied in organ baths. For in vivo investigation after anesthesia, carotid artery was cannulated for SBP measurement and jugular vein for drug administration. Then thoracic aorta was processed according to electron microscopy procedure. In SHR (9-week-old) SBP and relative heart weight were increased, acetylcholine induced relaxation of phenylephrine-precontracted aortal rings was reduced compared to Wistar rats. In losartan treated SHR SBP and relative heart weight were lowered. Impairment of acetylcholine-induced relaxation was prevented and neurogenic responses of mesenteric artery were suppressed. In vivo administration of acetylcholine (0.1µg, 1µg, 10µg) evoked similar decrease of SBP in SHR and Wistar rats. In losartan treated SHR the decrease of SBP was larger than in SHR and Wistar rats. Wall thickness (WT) and cross-sectional area (CSA) of the aorta in SHR were decreased compared to Wistar rats; inner diameter (ID) and WT/ID ratio were not changed. In losartan treated SHR ID was increased and WT/ID decreased while WT and CSA were not changed. Conclusion: Losartan administered to SHR (i) reduced SBP, (ii) prevented impairment of endothelium-dependent relaxation, (iii) improved integrated responses to acetylcholine, and (iv) reduced structural changes in the aortic wall.
Keywords— Hypertension, Conduit artery, Losartan, Neurogenic contraction, Structure.
Click here to Download Full Paper
AD Publications is a rapidly growing academic publisher in the fields of Engineering, Medical-Health, Environmental Science and Agriculture Research. AD Publications is a registered organization broad-based open access and publishes most exciting researches with respect to the subjects of our journals. The Journals is being indexed and abstracted by all major global current awareness and alerting services.
The organization aims at undertaking, co- coordinating and promoting research and development. It provides professional and academic guidance in the field of basic education, Higher Education as well in the Technical Education. Our Aims is to Promote and support, High Quality basic, Scientific Research and development in fields of Engineering, Medical-Health, Environmental Science and Agriculture Research and to Generate Public awareness, provide advice to scholar’s researchers and communicate research outcomes.
Some Important Links About Research Journal
International Journal
Agriculture Journal
Medical Journal
Environmental Journal
Engineering Journal