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Updated: Aug 26, 2026

Monitoring the Effect of Osmotic Stress on Secretory Vesicles and Exocytosis
Published on: February 19, 2018
Membrane and soluble proteins of adrenal chromaffin granules
1Department of Biochemistry, University of Edinburgh, Hugh Robson Building, George Square, Edinburgh, EH8 9XD, Scotland, UK.
Abstract:
Bovine adrenal chromaffin granules are useful 'model' neurosecretory vesicles, particularly for biochemical studies. The granule matrix contains three major secretory proteins (chromogranin A and secretogranins I and II) together with peptides derived from them, and smaller amounts of neuropeptides (enkephalins and neuropeptide Y). Several different endo- and exo-proteinases are also present in both soluble and membrane-bound forms. The major membrane proteins are those involved in catecholamine biosynthesis (dopamine beta-monooxygenase and cytochrome b(561)), active transport of granule components (vacuolar-type proton-translocating ATPase, and carriers for monoamines, nucleotides and small ions) and exocytosis (synaptotagmin, synaptobrevin and other proteins). In addition, the functions of a number of major granule membrane proteins remain unknown.
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