Electron microscopic autoradiographic analysis of the uptake and intracellular transport of H3-leucine by the rat submandibular gland acinar cells in tissue slices.

Uptake of H3-leucine into secretory product and its subsequent intracellular transport was analyzed by electron microscopic autoradiographic techniques in the rat submandibular gland acinar cells in vitro. The route and kinetic timetable of intracellular transport was established for the acinar cell secretory product by calculating the present of silver grains and relative grain density associated with the various organelles on a time sequence basis. Radioactivity was first associated with the rough endoplasmic reticulum; then the convex surface of the Golgi apparatus; the concave surface of the Golgi apparatus; and finetics of intracellular transport in the rat submandibular gland acinar cell with other established systems revealed only a difference in the exit of radioactivity from the concave surface of the Golgi apparatus.