Effect of colchicine on nuclear presence of two lysosomal enzymes in rat implantation sites.

The purpose of the study was to demonstrate that the effect of colchicine on the implantation and embryo development in rat is caused in part by its action on lysosome translocation to the perinuclear region. The subcellular enzymatic distribution of two lysosomal enzymes, acid phosphatase (E.C.3.1.3.2.) and beta-glucuronidase (E.C.3.2.1.3.1.), were measured. The right uterine horn was treated during preimplantation with colchicine (2 micrograms/kg of body weight on day 4) and the left with lumicolchicine (control). In the control horn, the nuclear activity of lysosomal enzymes was significantly higher in the implantation site tissue than the treated horn (colchicine) (p < 0.01). There were no modifications on the undecidualized endometrium under colchicine treatment. Simultaneously to this result, implantation and embryonic development were abolished. From the results presented herein, it is proposed that the inhibitory effect of colchicine is due to an inadequate biochemical differentiation at the implantation site, related to both arrest of cell division (mitosis is arrested in methaphase) and inhibition of the lysosomal movement toward the nucleus.