CHRONIC ALLERGIC PULMONARY INFLAMMATION IS AGGRAVATED IN ANGIOTENSIN-(1-7) MAS RECEPTOR KNOCKOUT MICE

The angiotensin-(1–7) [ANG-(1–7)]/Mas receptor pathway is currently recognized as a counterbalancing mechanism of the renin-angiotensin system in different pathophysiological conditions. We have previously described that treatment with ANG-(1–7) attenuates lung inflammation and remodeling in an experimental model of asthma. In the present study, we investigated whether lack of the Mas receptor could alter the inflammatory response in a model of chronic allergic lung inflammation induced by ovalbumin (OVA). Mas receptor wild-type (MasWT) and knockout (MasKO) mice were subjected to four doses of OVA (20 μg/mice ip) with a 14-day interval. At the 21st day, nebulization with OVA (1%) was started, three times per week until the 46th day. Control groups received saline (0.9% ip) and were nebulized with saline (0.9%). MasWT-OVA developed a modest inflammatory response and minor pulmonary remodeling to OVA challenge. Strikingly, MasKO-OVA presented a significant increase in inflammatory cell infiltrate, increase ...