An attempt to use vincristine and colcemid to measure proliferative rates in normal human epidermis in vivo.

A range of doses of vincristine (0.5-10 micrograms) or colcemid (5-100 micrograms) injected intradermally into normal volunteers failed to yield any significant accumulation of arrested mitoses. This was despite an apparently successful block of cells in metaphase by the highest three doses of each drug. Possible reasons for the failure to see accumulation are discussed. The results suggest that normal human epidermis is not a suitable system for application of the metaphase-arrest technique using intradermal injection.