LAUSR

Kidney ischemia-reperfusion injury (IRI) causes acute kidney injury with increasing risk of maladaptive repair through endothelin-1/ETAR signaling. Calcitriol shows renoprotection in kidney fibrosis, however, its effects on vasoactive substances expression and vascular remodeling following kidney IRI remain unclear. This research aimed to investigate Calcitriol's effects on ppET-1, ETAR, eNOS mRNA expression and vascular remodeling in acute and chronic phases of kidney IRI in mice. Twenty-five male Swiss mice were randomly divided into 5 groups (n=5): SO (Sham-operated), IR3 (3-day kidney IRI), IR12 (12-day kidney IRI), IRD3 (3-day kidney IRI+Calcitriol 0.5 μg/kgBW/day), IRD12 (12-day kidney IRI+Calcitriol 0.5 μg/kgBW/day). IRI groups underwent bilateral renal pedicles clamping for 30 minutes then reperfusion. Kidneys were harvested for Sirius Red staining to observe interstitial fibrosis and vascular remodeling, PCR to quantify ppET-1, ETBR, eNOS mRNA expression, and Western blotting to quantify ETAR protein expression. Calcitriol treatment in both phases of kidney IRI showed lower serum creatinine and ETAR protein expression, while higher eNOS and ETBR mRNA expression than IRI-only groups. Furthermore, ppET-1 mRNA expression was higher in IRD3 than IR3, but lower in IRD12 than IR12. Calcitriol also prevented vascular remodeling as indicated by lower wall thickness and higher lumen/wall area ratio than IRI-only groups.