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Introduction: Both age and gender can influence kidney function as well as renin-angiotensin system, and Mas receptor (MasR) as one of the components of depressor arm has more expression in female gender. The association between the receptor and age in renal vascular responses to angiotensin II (AngII) in male and female rats is completely unclear. Therefore, the aim of this study was to examine the effects of age and sex on systemic and renal vascular responses to AngII in Wistar rats with or without MasR antagonist (A779). Methods and Materials: Anesthetized Wistar male and female rats with two age ranges of adult (8-12 weeks) and old (24-28 weeks) underwent arterial and venous cannulation. Mean arterial pressure (MAP), renal perfusion pressure (RPP), renal vascular resistance (RVR) and renal blood flow (RBF) in response to the infusion of AngII with or without A779 were recorded and evaluated. Results: The baseline data (before A779 and AngII infusion) showed no significant changes in MAP, RPP, RBF, and RVR values between 8-12- week male and female groups. Although, RBF in the phase had a significant change between 24-28- week male and female groups (P < 0.05). The administration of A779 or vehicle could not influence the mentioned parameters in all experimental groups. On the other hand, the gender difference was observed in RBF and RVR responses to AngII administration in 8-12- week groups receiving vehicle or A779 (P < 0.05). However, the gender difference was not seen between 24-28- week groups. Conclusion: Advancing age could impress sex difference in RBF and RVR responses to AngII infusion, and it seems that the MasR could not participate in the responses. [ABSTRACT FROM AUTHOR]