Mitostatic action of vinblastine sulphate on oral epithelia of hamsters

Vinblastine sulphate at doses of 1 mg. 2 mg and 4 mg/kg body weight were administered intraperitoneally to 30 golden hamsters that were sacrificed after 1/2, 1, 2, 4 and 8 hours. The percentage of basal cells in each phase of mitosis was computed from epithelium of the cheek pouch, palate and tongue at the various time intervals. It was found that vinblastine at a dose of 4 mg/kg body weight produced total metaphase block in these epithelia from 1 hour after administration for at least 8 hours. The drug did not affect the rate of entry of basal cells into mitosis.