In basophils

Histamine in the Blood. After its release, histamine diffuses rapidly into the blood stream and surrounding tissues (12). Histamine appears in blood within 2.5 min after its release, peaks at 5 min, and returns to baseline levels by 15 to 30 min. In humans, the diurnal mean of plasma histamine levels is 0.13 ng/g. In urine, elevations of histamine or metaboUtes are more prolonged than plasma elevations. Consequendy, abnormahties are more easily detected by urinary histamine assay. About one-half of the histamine in normal blood is in basophils, one-third in eosinophils, and one-seventh in neutrophils the remainder is distributed among all the other blood components. Increases in blood histamine levels occur in several pathological... 

Heparin is biosynthesized and stored (probably as a complex with histamine and other basic species) in basophilic granules of mast cells of many animal tissues. (Mast cells, whose function remains largely obscure, are located in connective tissues, near the capillaries, and in the walls of blood vessels.10 28 27)... 

The answer is d. (Katzung, pp 336-3373 The inhibitory effect of mediator release of cromolyn is cell specific In mast cells exposed to cromolyn, inhibition of the early response occurs to antigen challenge, while in eosinophils, it affects the late response, and in basophils it has almost no effect on mediator release. Cromolyn is effective in anti gen-induced asthma, occupation-exposure asthma, and in some cases of intrinsic asthma. Administration of cromolyn by inhalation is most effective in treating patients. 

Somatostatin (SOM), initially identified by its ability to inhibit the release of growth hormone, is known to have inhibitory effects on a variety of cells [ 109], In mast cells and in basophils, SOM, like NT, has inhibitory as well as stimulatory effects depending on the concentration used. At high concentrations (> 10 8 M), SOM is a powerful stimulus of peritoneal mast-cell secretion (from both normal and athymic rats) and resembles other non-immunologic secretagogues such as compound 48/80, SP and NT in that it triggers a rapid exocytosis that is primarily dependent on cellular Ca [ 110,111], A similar effect is seen in vivo when injected into skin or skin blisters at high concentrations (> 10-8 M), SOM causes a rapid, dose-dependent release of histamine [88, 112] but when used at concentrations lower than those which elicit a secretory... 

Newborn healthy infants vary in their total leukocyte counts from 9,000 to 30,000 per cu. mm., in neutrophils from 6,000 to 26,000, in eosinophils from 20 to 850, in basophils from 0 to 640, in lymphocytes from 2,000 to 11,000, and in monocytes from 400 to 3,100. In healthy adults the total leucocytes vary from 3,500 to 14,800, which may be distributed within the following ranges ... 

Inhaled and intravenous histamine causes bronchoconstriction as one of the first recognized properties of histamine, which is inhibited by Hi antihistamines. As a manifestation of airway hyperresponsiveness, asthmatic individuals are more sensitive to the bronchoconstrictor effect of histamine than normal individuals. In addition, in vitro studies have shown increased histamine release in basophils and mast cells obtained from asthmatic subjects compared with... 

Histamine (B). Histamine is stored in basophils and tissue mast cells. It plays a role in inflammatory and allergic reactions (p. 72, 326) and produces bronchoconstriction, increased intestinal peristalsis, and dilation and increased permeability of small blood vessels. In the gastric mucosa, it is released from enterochromaffin-like cells and stimulates acid secretion by the parietal cells. In the CNS, it acts as a neuromodulator. Two receptor subtypes (G-pro-tein-coupled), H and H2. are of therapeutic importance both mediate vascular responses. Prejunctional H3 receptors exist in brain and the periphery. 

CCR4 was originally cloned by Power and colleagues from a basophilic cell line (163). RNA for CCR4 is expressed in stimulated T-cells, B-cells, monocytes, platelets, and, to a lesser extent, in basophils (163,164). CCR4 has been... 

Histamine is a low-molecular-weight amine compound formed by decarboxylation of histidine and is stored in basophil and mast cell granules. The release of histamine from these cells is triggered by antigen cross-linking IgE bound to specific receptors on the surface membranes of mast cells and basophils. The tissue effects of histamine are evident within 1 to 2 minutes, but it is rapidly metabolized within 10 to 15 minutes. The major effects of histamine on target tissues include increased capillary permeability, contraction of bronchial and vascular smooth muscle, and hypersecretion of mucus glands. 

We have also demonstrated that low concentrations of protein Fv induce IL-4 secretion from basophils [19]. A study in which we examined IL-4 expression in resting basophils and in protein Fv-stimulated basophils demonstrated that protein Fv induced an increase in IL-4 similar to that obtained with anti-IgE (fig. 2). The stimulation of IL-4 synthesis in basophils by protein Fv was mediated by interaction with IgE. In fact, brief exposure to lactic acid completely blocked the effect of protein Fv and of anti-IgE on IL-4 secretion from... 

There was a significant increase on the 14th day which lasted until the 16th day. Between the 16th and 18th day the number of basophils dropped to its normal value. This increase in basophils is not regularly progressive (Fig. 25). 

In 1960 WiNQuisT induced a basophilia in guinea pigs between the 10th and 14th day by the injection of horse plasma. We call attention to the fact that this author s graph shows an almost significant increase in basophils on the 2nd day, which is followed by a drop in the graph, which is comparable to that recorded in our experiments. 

Summary the increase in eosinophils is a lasting phenomenon, differing in intensity with CA and PA, but non-existent with DNCB while the increase in basophils is a transient phenomenon common to the 3 ec ematogens with which we experimented. We do not observe significant variations in lymphocytes throughout the course of the sensitisation treatment. 

Already in 1902 Levaditi described a basophilia in the guinea pig and rabbit during the course of sensitization with foreign proteins. Schlecht (1909/10) and Winqvist (1960) also reported an increase in basophils following an injection of serum or heterogeneous plasma into guinea pigs. 

Thus, the increase in basophils that we observed links sensitisation with chemically simple substances to a larger phenomenon, that is, sensitisation in general. 

Ogasawara H, Fujitani T, Drzewiecki G, Middleton EJ. The role of hydrogen peroxide in basophil histamine release and the effect of selected flavonoids. J Allergy Clin Immunol 1986 78 321-328. 

In an isolated culture of ECL cells, a linear increase in gastrin-stimulated HDC activity was noted over 60 minutes. HDC levels were elevated up to threefold during this time. In a similar system of acutely isolated ECL cells, it has been noted that gastrin stimulated HDC activity with an ECso of 10- M and an EC of 10 M. Maximal stimulation resulted in a time-dependent increase of HDC activity, with linear kinetics up to 30 minutes, and no further increase between 30 and 60 minutes. In basophil leukemia cells, phorbol esters have been noted to increase HDC gene expression after 2 to 4 hours of incubation by 50% due to increased protein synthesis. The accelerated time course and amplified levels of HDC noted in ECL cells suggest that a second factor, such as posttranslational activation of HDC, might be involved, rather than only stimulation of HDC synthesis. 

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