Unknown

Four or six consecutively sliced skins were placed into 5 ml of 40% PEG400 solution with a 60– 80% concentration of EA (β-Estradiol 17-acetate) saturated concentration (26.9 +/- 1.0 mg/ml). The slices were then incubated in the elution medium at 36C. Samples (750 ml) of the solution were withdrawn at predetermined time intervals and the same volume of ethanol was added to the sample for removing proteins and the OCT compound. The mixture of 40% PEG400 solution and ethanol was then centrifuged for 10 min at 10,000 x g. After filtering the supernatant (0.45 mm PTFE, Alltech Association Inc., Deerfield, IL, USA), the concentrations of EA and E (Estradiol) were assayed by high performance liquid chromatography (HPLC).