3.25 in. x 4 in. Lantern Slides and The guinea pig pancreatic lobule preparation was developed in the laboratory of Dr. Jamieson at the Rockefeller. It was later adapted in these studies to demonstrate that newly synthesized exocrine pancreatic enzymes and proenzymes are packaged into condensing vacuoles and zymogen granules in synchrony, and are secreted in parallel upon stimulation in vitro by secretagogues. The advantage of the lobule preparation was rapidity of harvesting lobules in sufficient numbers for morphologic studies and cell fractionation with superior preservation of structural and functional characteristics over prolonged (12 hr. or more) incubation periods in vitro.
3.25 in. x 4 in. Lantern Slides, Original Magnification: x17,000, and Pulse chase experiments, carried out by Jamieson and Palade, defined the kinetics and pathway of intracellular transport of newly synthesized proteins in guinea pig pancreatic slices in vitro. The 3 min pulse consisted of preincubation in the cold in a leucine-free medium containing tritiated leucine, followed by warming up to 37 for 3 min. Chase incubations followed by incubation in medium containing an excess of "cold" leucine, fixation at indicated times, and processing for EM autoradiography. Historic details in the Nobel Lecture 1974 by Dr. Palade.
3.25 in. x 4 in. Lantern Slides, Original Magnification: x1,000, and Zymogen granule fractions were isolated from pancreatic slices pulse labeled and incubated in vitro. Processing for EMAR was as for tissues.
