Liver cell hyperplasia: on the suitability of using the metaphase-arrest technique.

This study has explored the possibility of applying the metaphase-arrest method with colchicine to two models of induced liver growth in the rat, regenerative growth and phenobarbital-induced growth. At a dosage of 0.5 mg/kg body weight (BW), colchicine caused a linear accumulation of mitoses for up to 90 min when administered at 3 days after the start of phenobarbital treatment; however these mitoses included a number of anaphases and telophases. No anaphase escape was seen when this dose of colchicine was given at various times after partial hepatectomy, though the arrested mitoses were invariably more fragmented and some may have even degenerated beyond recognition as early as 90 min after injection. It is concluded that the optimal dose of stathmokinetic agent is heavily dependent on the relative liver weight, and thus would change continuously during compensatory hyperplasia.