Reduction of tissue histamine by compound 48/80

Abstract

It is widely accepted that histamine can be released under various conditions from the tissues, but scarcely anything is known about its restoration. One of the reasons for this gap in our knowledge has been the lack of a method by which a tissue could be depleted of its histamine and the subsequent changes in histamine content followed up. The position has been changed in recent years by the findings, particularly those of MacIntosh & Paton (1949), that there exist a number of substances which have the property of releasing histamine from a tissue without producing visible structural damage. These substances are generally referred to as histamine liberators. In the experiments of the present paper they have been injected into animals in order to reduce the histamine content of a tissue and to find out how long it takes for the tissue to regain its original histamine level.If this restoration were to proceed quickly, factors influencing the rate of restoration might be studied; if it were to proceed slowly, it would be possible, in addition, to study in a more or less histamine depleted tissue, reactions for which histamine is assumed to play a dominant role.Local and general reduction of tissue histamine could be obtained in several organs such as skin and skeletal muscle, and it was found that restoration to normal histamine level was a slow process. Two skin phenomena which are attributed to release of histamine were then studied in such histamine depleted skins: (1) the anaphylactoid reaction of rats to egg-white and (2) the reactions to light of rats photosensitized with haematoporphyrin. METHODSThe experiments were carried out in dogs and rats. The histamine liberator mainly used was 48/80

5-Hydroxytryptamine and Histamine as Mediators of the Vascular Injury Produced by Agents Which Damage Mast Cells in Rats

“…Our experiments do not bear this out: There are no apparent mast cell--damaging effects with large doses of 5-hydroxytryptamine; the edema produced by histamine can be completely inhibited without affecting the edema produced by 5-hydroxytryptamine. Furthermore we have not found following repeated local injections of 5-hydroxytryptamine the refractory state seen following repeated injections of ovomucoid (1) or other known "histamine releasers" (18).…”

Histamine release as cause of acute hypotension following rapid colloid infusion

“…The increase in the histamine concentration in the whole blood of dogs was observed only when a hypotensive reaction took place; thus, the taehyphylaxis against the hypotensive reaction due to gelatine also favorizes the concept of a liberation of mast cell histamine. Tachyphylaxis is regarded as characteristic for liberators of mast cell histamine (Feldberg and Talesnik, 1953).…”

Macrocolony Assays in the Rat of Allogeneic Y-P388 and W-256 Tumour Cells Injected Intravenously: Dependence of Colony Forming Efficiency on Age of Host and Immunity

“…5) (Feldberg and Talesnik, 1953) has been found to increase growth of a heterologous tumour in rats (van den Brenk and Upfill, 1958) and to increase survival of skin homografts in rats (Boyd and Smith, 1960 (Biozzi, Benacerraf and Halpern, 1953). Pretreatment of rats with a single large intravenous injection of 0 3 ml of india ink (Pelikan) given with a view to inhibiting the functions of macrophages present in the various tissues of the rat, had no significant effect on CFE, neither in weanling nor in older rats.…”