[Lysosomal activity in prolactin cells under the effect of a dopamine agonist]

The influence of bromoergocryptine, a dopamine agonist used in clinical praxis, on hormone degradation by the lysosomal system was studied in the pituitary mammotrophs of female rats. Immunocytochemistry of prolactin (protein A-gold technique) combined with the electron-microscopic visualization of the lysosomal system by its non-specific esterase activity (gold thiol-acetic acid method) revealed that bromoergocryptine administration increases the spatial extent of both the lysosomal and the hormone storage compartments with a considerable overlap and interaction between them. This change in compartmentalization may be effective in eliminating hormone excess and preserving cell integrity after release inhibition.