the effect of media supplementation with angiotensin on developmental competence of ovine embryos derived from vitrified-warmed oocytes

background: this study was aimed to assess the effects of angiotensin ii (ang ii) supplementation to the in vitro maturation (ivm) and in vitro culture (ivc) media of vitrified-warmed ovine oocytes on their developmental competence and expression of na+/k+/atpase in resulting embryos. methods: the slaughterhouse-derived immature oocytes (n=1069) were randomly distributed into four experimental groups: groups i and ii) ivm/ivf and ivc of fresh and vitrified oocytes without angiotensin supplementation (control-fresh and control-vit groups, respectively); group iii) ivm of vitrified oocytes in the presence of ang ii followed by ivf/ivc (vit-ivm group); and group iv) ivm/ivf of vitrified oocytes followed by ivc wherein the embryos were exposed to ang ii on day 4 of ivc (vit-d4 group). the embryos were immunostained with primary antibodies against na+/k+/atpase α1 and β1 subunits. results: in vit-ivm and vit-d4 groups, the rates of expanded and total blastocysts on day 7 as well as the proportion of blastocysts on day 8 were increased. the expression of na+/k+/atpase α1 and β1 subunits were positively influenced by the addition of ang ii on day 4 (vit-d4 group). conclusion: the addition of ang ii to the ivm and ivc media could improve blastocysts formation in vitrified sheep oocytes. this improvement might be related to the greater expression of na+/k+/atpase α1 and β1 subunits when ang ii was added during ivc.