[The adrenoreceptor blocker prazosin does not prevent synchronization of the protein biosynthesis rhythm by exogenous gangliosides in the hepatocyte culture].

We studied the effect of the alpha 1-adrenolytic prazosine on dense cultures of hepatocytes, which are normally characterized by the protein synthesis rhythm, and diluted cultures, in which such a rhythm is revealed after external synchronization. Exogenous gangliosides (a fraction of the total gangliosides of the bovine brain) then synchronize the rhythm in diluted cultures; this effect is also displayed in the presence of 10(-7) M prazosine. The synchronizing effect of the medium conditioned by dense cultures was also preserved in the presence of prazosine. In the dense cultures that don't normally require external synchronization, prazosine affected intensified the rhythmic patter of changes in the protein synthesis. After a total of 0.3 microM gangliosides were introduced in the medium with prazosine-pretreated dense cultures, the protein synthesis rhythm was visualized. We propose that, while blocking adrenoreceptors, prazosine does not prevent the action of exogenous synchronizing factors on the hepatocytes, but inhibits the release of such factors from the cell.