5 bromo 2 deoxyuridine brdu solution

Five-week-old male C57BL6 mice were used for chronic oral CORT exposure. Mice were divided into 5 groups: control group (n = 10), CORT-treated group (n = 10), CORT + NYT (500 or 1000 mg/kg)-treated group (n = 10), CORT + imipramine-treated group (n = 10). Mice were administered CORT (100 μg/mL; Sigma-Aldrich, St. Louis, MO, United States) in place of drinking water for 14 days. Animal were weaned with 50 μg/mL CORT for 3 days and then with 25 μg/mL CORT for 3 days to allow for gradual recovery of endogenous corticosterone secretion. NYT (500 or 1000 mg/kg/day) was orally administered once daily from day 21 to day 49. As a positive control, imipramine (10 mg/kg/day, intraperitoneally (i.p.); Wako Pure Chemical, Osaka, Japan) was administered once daily. Subsequent behavioral tests were performed on days 50–64 and brain samples were collected on day 65. On the days behavioral tests were performed, the drugs were administered 30 min before the tests. A 5-bromo-2-deoxyuridine (BrdU) solution (50 mg/kg/day, i.p.; Sigma-Aldrich) was administered from day 15 to day 19.

For zebrafish studies, one-year-old zebrafish were maintained in 6 L of water containing 200 ppm diethylnitrosamine (DEN; Sigma Chemical Co, St Louis MO.) for 3 or 8 weeks, with the water changed once per week. Treated fish were then exposed to 75 mg/L 5-bromo-2′-deoxyuridine (BrdU) solution (Sigma Chemical Co, St Louis MO.) for two days. Fish were sacrificed and cell proliferation analyzed by immunohistochemistry. Preneoplastic foci and tumor types were identified by their size and pattern of HE staining under a light microscope. For HHM transgenic medaka studies (see below), fish were reared in 6 L of water containing 100 ppm DEN for 3 weeks, during which the water was changed weekly. Treated fish were then exposed to 75 mg/L BrdU for 2 days as described above [16 (link)]. Fish were sacrificed and cell proliferation analyzed as above. Homozygous, heterozygous and control HHM transgenic medaka were all reared in the same aquarium during DEN treatment.