Effects Of Hypoxia On Broiler Pulmonary Vascular Remolding And The Expression Of Endothelin-1and Its Receptors

To investigate the effects of hypoxia on broiler pulmonary vascular remolding and the expression of ET-1and its receptors,introduded600AA1-day-old broilers from low-altitude areas, and keeped them in pasture that affiliated with Agriculture and Animal Husbandry College of Tibet. AA broilers were randomly divided into2groups (A and C), Group A received no treatment. Group C is the control group, fed in aerobic room. Experiments were conducted28days, in every week, captured20broilers randomly, weighed and measured growth performance and cardiac index, statisticed incidence of ascites. In each period, part of the lung tissue, and made into paraffin sections. A part of them was dyed with the method of H.E to observe dynamic changes of pulmonary vascular remodeling during the process of pulmonary hypertension. The technology of immunohistochemistry was adopted to observe the expression of ET-1and its receptors, and conducted semi-quantitative analysis of immunohistochemical images by using image-pro plus image analysis system, the purpose was to study the dynamic changes of ET-1and its receptors’expression during the process of pulmonary hypertension. The results showed that oxygenation significant decreased incidence of ascites, and increased growth performance and suggested oxygenation significant decreased ascites incidence and increased growth performance at the high altitude environment, hypoxemia is the key factor in the development of poultry ascites.(2) The sections of lung tissues which stained by H.E, the epithelium of lung rooms proliferated in sick broiler, the pulmonary capillary expanded irregularly, and the pulmonary artery mooth muscle between interlobulars proliferatived severely. The results indicated that sustained pulmonary hypertension hypoxia could lead to pulmonary vascular remodeling.(3) In the process of pulmonary hypertension induced by the hypoxic environment, from the first to third week-old, the experimental group of ET-1and ETA-R expression levels tended to increase, the average optical density of ET-1and ETR-A of experimental group was significantly higher than the control group in the third and the fourth week-old. The average optical density of the ETB-R was significantly lower than the control group in the fourth week-old, Under hypoxic conditions, the expression level of ET-1and its receptor in the experimental group generally higher than the control group. ET-1and its receptor involved in the process of pulmonary hypertension by changs of expression.