The release of histamine / by W.D.M. Paton.

  • William Paton
Date:
1958
Catalogue details

Licence: In copyright

Credit: The release of histamine / by W.D.M. Paton. Source: Wellcome Collection.

    10/72 page 86
    their sensitivity to it; indeed, some of the mast cells resist the drug completely even when very large doses are given. Further, it is interesting that if the administration of a histamine liberator is continued, restitution of some of the mast cell population occurs even during the continued presence of the drug. Finally, it is worth noting that in the mouse even vigorous treatment with Compound 48/80 may leave as much as 50% of the subcutaneous mast cells intact (Riley and West, 1955 a, 1955 b). The cause of the differential sensitivity of the mast cells is unknown, but it is a reminder that they are not cells with constantly uniform reactions. Although this article is primarily concerned with histamine it is important to note that mast cells certainly contain other sub¬ stances. Heparin has long been known to be a constituent of the mast cell, and it was indeed the fact that chemical histamine liberators released heparin as well that prompted the investigation by Riley and West as to whether histamine was also present in mast cells. But in addition to heparin there is now evidence that 5- hydroxytryptamine occurs in the mast cell, perhaps in about 1/10 of the amount of histamine present, and released by procedures which disrupt the cell such as the action of the histamine liberators (.Bhattacharya and Lewis, 1956). There are also a number of enzymes, including phosphatase, succinoxidase, phosphoramidase, histidine decarboxylase, and an enzyme resembling chymotrypsin (Montagna and Noback, 1947; Schayer, 1956; Benditt, 1956). It is therefore misleading to think of the mast cells solely as reservoirs of histamine and heparin. Indeed the possibility cannot be excluded yet that their histamine content is incidental to some other more important function. This, however, is rendered less likely by the recent discovery (Schayer, 1956) of histidine decar¬ boxylase in the mast cell, and the ability of the mast cell to form and bind histamine. The distribution of histamine has been followed to the intra¬ cellular level. It is interesting that as long ago as 1938 Trethewie showed that it was possible to obtain, from dog liver, particles in cell-free extracts which contained histamine and which would release this histamine on heating; he made similar observations for acetylcholine. His words are worth quoting: “the cell cannot be regarded as a “diffusion-tight compartment” in the interior of which histamine or acetylcholine is freely diffusible. There is no experimental evidence for the assumption of a “precursor” or
    digitised image 1
    digitised image 2
    digitised image 3