Can examination of tissue stained with Oil red O be postponed up to three months?

Introduction: As far as we know, there are no known studies on the durability of frozen tissue stained with Oil Red O. The purpose of this study was to examine if the lipid drops in Oil Red O stained tissue keep the original position and color over time (3 months). Further we examined if storage position of the stained tissue makes a difference. Method: We used ten frozen kidney sections stained with Oil Red O. Half of the samples were stored vertically and the other half horizontally, and photos of the same areas were taken within the first 24 hours after staining, and then after 48 hours, 72 hours, 7 days, 14 days, 1 month, 2 months and 3 months respectively. Results and conclusion: No changes in position of the lipids were observed. The color of the staining faded somewhat over time, but it was still possible to distinguish the positive sites from the negative.