5-Chloro-2'-deoxyuridine

Cell experiment:

Human erythroleukemia K-562 cells are used throughout the study. Cells are initially seeded at 1.0×105 cells/mL and treated with either 10 μM 5-Chloro-2’-deoxyuridine or 10 μM thymidine (negative control) for 63 h, or two cell doublings. Cells are counted by trypan blue exclusion, pelleted by centrifugation (500×g) and washed with 10 mL sterile PBS[1].

Animal experiment:

Rats[2]Adult, male Wistar rats, weighing 200-250 g are used. Firstly, the animals are allowed to self-administer methamphetamine at a dose of 0.05 mg/kg/injection under a fixed-ratio 1 (FR1) schedule for baseline sessions. After that, the rats are divided into four groups. Two groups of rats (long-access; LgA-4 days (d), LgA-13 d; n=7 per group) are allowed to self-administer 0.05 mg/kg/injection of methamphetamine for 6 h per day, whereas the other groups (short-access; ShA-4 d, ShA-13 d; n=7 per group) are allowed to do so for 1 h per day. All procedures are performed during the dark cycle. On day 5, ShA-4 d and LgA-4 d rats receive one injection of 50 mg/kg 5-chloro-2’-deoxyuridine and survive for 30 min. On day 14, ShA-13 d and LgA-13 d receive one injection of 50 mg/kg 5-Iodo-2’-deoxyuridine followed by 50 mg/kg 5-chloro-2’-deoxyuridine 2 h later. These rats also survive for 30 min after the 5-Chloro-2'-deoxyuridine injection. A parallel group of drug-naive rats (n=6) receive one injection of 50 mg/kg IdU followed by 50 mg/kg 5-Chloro-2'-deoxyuridine 2 h later. These rats also survive for 30 min after the 5-Chloro-2'-deoxyuridine injection[2].

References:

[1]. Kim CH, et al. Polymerase incorporation and miscoding properties of 5-chlorouracil. Chem Res Toxicol. 2010 Apr 19;23(4):740-8.
[2]. Yuan CJ, et al. Extended access methamphetamine decreases immature neurons in the hippocampus which results from loss and altered development of neural progenitors without altered dynamics of the S-phase of the cell cycle. Pharmacol Biochem Behav. 2011 Nov;100(1):98-108.