Biliary hypertension as the cell proliferation trigger in bile duct ligated rats.

The aim of the study was to investigate the relationship between biliary pressure dynamics and proliferative activity of cholangiocytes and hepatocytes in BDL setting. 30 white Wistar male rats, weighting 200-220 gr. were involved in the modelled biliary hypertension setting induced by common bile duct ligation (CBD). The pressure in CBD was measured before (I) and at 1st (II), 3rd (III), 72nd (IV), 96th (V), 120th (VI) and 144 th (VII) hours after its ligation, with following data registered respectively: 169.67+/-4.16 (I), 205.0+/-1.0 (II), 213.67+/-3.06 (III), 252.67+/-3.51 (IV), 270.67+/-2.52 (V), 277.33+/-3.21 (VI) and 285.67+/-2.52 (VII) mm H(2)O. Pressure in portal vein was measured before (I) and at 1st (II), 6th (III), 24th (IV), 72nd (V) and 144 th (VI) hours past the bile flow obstruction. The corresponding indices were: 103.67+/-3.51 (I), 107.33+/-4.16 (II), 123.33+/-2.08 (III), 58.00+/-1.73 (IV), 172.00+/-3.61 (V) and 190.67+/-4.93 (VI) mm H(2)O. Liver histology was studied on paraffin embedded and Hand E stained slides in every above mentioned terms of CBD ligation. Mitotic indices for proliferating cholangiocytes and hepatocytes were counted at 24th, 48th, 72nd, 96th and 144 th hours after CBD ligation. The outcomes revealed that ductular reaction appears just in the first hours after CBD ligation. However the mitoses of epitheliocytes reach their peak (18.0+/-1.3) at 3rd day but mitoses of hepatocytes (31.5+/-2.1) - at 4th day after bile flow obstruction. Consequently, the following conclusions were made: biliary and portal hypertension, induced by the first respectively, represent the proliferative triggers for biliary ductules, cholangiocytes and hepatocytes in common biliary duct occlusion setting; However, dynamics, as well as the mechanisms of this process require further comprehensive investigation, including not only reduced inter-experimental term intervals and refinement of morphological and/or molecular - biological techniques of the study, but also the development of new, different experimental models.