Distribution of intracellular and surface components labeled with mannose-3H in amoebae exposed to the local anesthetic lignocaine.

Following injection with mannose-3H, which is a precursor to cell surface components, amoebae were exposed to the local anesthetic, lignocaine. Electron microscope radioautographs were prepared at intervals between 1 and 24 h after injection, and the distribution of silver grains over various parts of control and treated cells was determined. Control amoebae displayed successive peaks of radioactivity associated with the Golgi apparatus, cell surface, and "fringed" vacuoles. In the presence of lignocaine, incorporation of precursor into the Golgi apparatus and endoplasmic reticulum at the early intervals was inhibited, a result suggesting that glycosylation of surface components diminished. At later times, the proportion of grains associated with the cell surface and fringed vacuoles of treated cells decreased while that over lysosomes increased compared to controls. The changes in patterns of labelling of the Golgi apparatus and cell surface in lignocaine-treated amoebae resembled alterations previously observed in amoebae exposed to a general anesthetic. However, the effects of local and general anesthetic agents on the endoplasmic reticulum, lipid droplets, and lysosomes differed.