Granules, intracellular

Cathepsins are intracellular proteinases that reside within lysosomes or specific intracellular granules. Cathepsins are used to degrade proteins or pqffides that are internalised from the extracellular space. Some cathepsins such as cathepsin-G or cathepsin-K may be released from the cell to degrade specific extracellular matrix proteins. All cathepsins except cathepsin-G (serine) and cathepsin-D (aspartyl) are cysteine proteinases. 

Cells containing Hb-F are densely stained with erythrosln and cells with Hb-A appear as ghost cells Intermediate cells are stained more or less pink. Reticulocytes with Hb-A sometimes resemble Intermediate cells and may also show some Intracellular granulation. Inclusion bodies are visible In eluted cells as compact particles of differing sizes. Figure 10 gives some examples. The method Is Ideally suited to demonstrate the presence of newborn red cells In the maternal circulation. The method Is also widely used for the evaluation of the distribution of Hb-F within red cells mainly to differentiate between the HPFH condition and the 3 or 36 thalassemias. Evaluation of F cell smears In such cases Is difficult the term "equal distribution" usually Indicates the presence of Hb-F In each red cell but not necessarily In the same amount. 

The antimicrobial neutrophil proteins are located within intracellular granules. Approximately 30% of all neutrophil granules contain myeloperoxidase, and these azurophilic granules are the first granule types to be... 

These suggestions may go some way toward explaining the occurrence and composition of intracellular granules and it is easy to envisage how such a system could evolve into a mechanism where the deposits became involved in the variety of purposes normally associated with biomineralization454 ... 

Platelet participation in normal hemostasis. The hemostatic plug is the specific response to external vessel lesion and depends on the extent of vessel wall damage, the specific interaction between endothelial cells and activated platelets, release of the contents of platelets intracellular granules in response to activation, the conjoint activity of activated factor Vll and platelet agonists, and the open conditions of blood flow. After activation, platelets also produce the external ization of membrane phosphatidylserine through the flip-flop mechanism that will support the function of the prothrombinase complex ending in thrombin generation and local clot formation. 

To date, neither the stoichiometry nor the electrogenicity of serotonin uptake has been resolved, the evidence gleaned from intact cells being different from that for isolated vesicle systems. A further complication to the study of biogenic amine transport is the fact that there are cellular granules which act as storage sites in neural cells (and other cells as well, e.g., platelets) so that a second level of transport occurs inside the cell. These intracellular granules have an ATP-ase which creates... 

Hopkin S. P. and Nott J. A. (1979) Some observations on concentrically structured intracellular granules in the hepatopancreas of the shore crab Carinus maenas (L.). J. Mar. Biol. Assoc. UK 59, 867-877. 

Howard B., Mitchell P. C. H., Ritchie A., Simkiss K., and Taylor M. (1981) The composition of intracellular granules from the metal-accumulating cells of the common garden snail (Helix aspersa). Biochem. J. 194, 507-511. 

Stimulating the release of these neurotransmitters stored in intracellular granules or (2) inhibiting the uptake of synaptic levels of these neurotransmitters by membrane transporters. Direct-acting drugs, in contrast, act on pre- or postsynaptic receptors to affect ap-... 

GH is synthesized by the somatotropic (acidophilic) cells of the adenohypophysis and is stored within intracellular granules. During the daytime hours, the plasma concentration of GH in normal adults remains stable and relatively low (<2ng/mL), with several secretory spikes occurring approximately 3 hours after meals and after exercise. In contrast, during the evening hours, adults and children show a marked rise in GH secretory activity 90 minutes after the onset of sleep GH concentrations reach a peak value during the period of deepest sleep. This pattern of GH secretion... 

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