Improved isolation of the crustacean hyperglycemic hormone-containing granules from sinus glands of Carcinus maenas (Linnaeus, 1758)

An improved neurosecretory granule (NSG) preparation of the shore crab, Car cinus maenas sinus glands, enriched for members of the crustacean hyperglyc emic hormone family (CHH) and almost devoid of contaminating subcellular fr actions, was obtained by differential and density-gradient centrifugations. CHH was determined in an aliquot of each fraction by means of a specific r adioimmunoassay, and purity of the fractions by means of electron microscop y of pellet sections from duplicate tubes. Fraction F-3 from the first disc ontinuous gradient centrifugation was enriched for CHH-containing NSG and p urified on a second, shallower discontinuous gradient, and fraction F-3b pr oved to contain solely CHH granules as revealed by EM and RIA criteria.