The influence of immunosuppressants on the morphology, proliferating cell nuclear antigen (PCNA) and apoptosis in the rat ventral prostate.

Aim: Analysis of the impact of immunosuppressants on apoptosis and PCNA in the rat ventral prostate.

Method: The studies were performed on 48 male Wistar rats. The animals were divided into a control group and 7 experimental groups. For 6 months, the rats were administered drugs such as: rapamycin (Rapa), cyclosporin A (CsA), tacrolimus (Tac), mycophenolate mofetil (MMF) and glucocorticosteroids (GS). During section of the rats, prostate ventral lobes were obtained. Morphological evaluation (HE, PAS), TUNEL assay, PCNA expression analysis and quantitative image computer analysis were performed.

Results: The highest percentage of apoptosis in epithelial cells was observed in groups which received two combinations of drugs: (V) CsA, MMF, GS and (VII) Tac, MMF, GS. A much lower percentage of apoptotic epithelial cells was found in the groups where the treatment schemes included rapamycin throughout the duration of the study. Interestingly, the conversion of the treatment to rapamycin caused a significant reduction of apoptosis in epithelial cells as well as in proliferation in both epithelial and stromal cells.

Conclusions: On one hand, the obtained results may explain the anticancer activity of rapamycin in reducing the proliferation of epithelial cells, and on the other hand the adverse effect of rapamycin in the form of reduced regeneration of these cells. Taking into account the prostate in isolation from other organs/systems, the dosage scheme with Rapa, Tac and GS would appear to be the most favorable, due to the smallest morphological changes.