Morphology and biochemical activity of rat liver golgi complexes after pretreatment with bis(kojato)oxovanadium(IV) or kojic acid alone

The authors studied the effect of a short (2 days) oral treatment of rats with bis(kojato)oxovanadium (IV) [VO(ka)2] as 1.8 mmol liquid solution on the biochemical activity and morphology of liver Golgi complexes (Group pVC). Such a short treatment induced greater changes than a longer (1 week) application of the same vanadium compound, what had been observed previously. Especially the Golgi marker enzyme activity (GalT) was the highest among all the investigated groups, and additionally, the greatest dispersion of result was obtained in this group. This group of animals showed twisted Golgi complexes, which--apart from 2-3 narrow cisterns--often contained 1-2 grossly distended cisterns filled with clear, floccular contents. The fairly long cisterns were irregular in shape and were often bent, forming ring-like structures. In the second experiment, we studied the effect of the ligand alone (kojic acid) (Group C+ka2) employed in the same way as in the case of the previously used vanadium complex (time and concentration). The biochemical parameters (body and liver weight, liquid and food intake, blood sugar level and GalT activities) were the same as in the untreated control group (C). Contrary to the biochemical findings, the morphology of Golgi complexes changed in effect of 3.6 mmol kojic acid application (the same application, time and concentration as in the whole complex with vanadium) over a 1-week period, manifesting the stimulation of exocytosis (in the trans region and directed toward plasma membrane), with the cisterns of Golgi dictyosomes being rounded or oval in more than 85% of cases. In this group, electron microscopy revealed the presence of two types of Golgi complexes, namely 2-3 short, slightly arched cisterns grossly distended at both ends and filled with clear, floccular material, as well as vacuoles with the same contents, which were visible in the vicinity of the cisterns. The other type, which was observed less frequently, was represented by Golgi complexes formed by haphazardly twisted cisterns.