Passive cutaneous anaphylaxis

Chloro-oxazolo[4,5-/i]quinoline-2-carboxylic acid methyl ester was the most active compound in tests for inhibitors of antigen-induced release of histamine in vitro from rat peritoneal mast cells (IC50 of 0.3 p,M) and as inhibitors of IgE-mediated passive cutaneous anaphylaxis in the rat (ED50 (intraperitoneal) of 0.1 mg/kg in dose 0.5 mg/kg as an inhibitor of the test)—10 times and 60 times more potent, respectively, than the disodium salt of cromoglycic acid (85JMC1255). 

Reaction of 2-aminoquinoline derivatives with BrCH2C0C02Et gave imidazoquinoline-2-carboxylate 473 which upon hydrolysis with sodium hydroxide gave the corresponding acid which had been tested against the passive cutaneous anaphylaxis (78GEP2802493, 78BEP858605) (Scheme 79). 

Although human anaphylaxis is a systemic reaction, the mouse model of passive cutaneous anaphylaxis (PGA) has been used extensively to enhance our understanding of mechanisms which also may contribute to systemic anaphylaxis. Unlike systemic anaphylaxis in the mouse, PGA appears to be entirely dependent on mast cells [4,6]. While IgE appears to be the primary antibody isotype that mediates PCA reactions in actively immunized mice, activation of FcyRIII by a fraction of IgGl antibodies (called anaphylactic IgGl) can also mediate PCA reactions in mice [4]. 

Fig. 2. IgG-mediated systemic versus local anaphylaxis, a IgG-mediated systemic anaphylaxis. When allergen-IgG immune complexes are formed in the circulation, basophils immediately capture them through IgG receptors on their surface and are activated to release PAF, that in turn act on vascular endothelial cells, leading to increased vascular permeability, b Passive cutaneous anaphylaxis. When allergen-IgG immune complexes are formed in the skin, they stimulate tissue-resident mast cells to release chemical mediators such as histamine, leading to local inflammation. 

Arimura A, Nagata M, Takeuchi M, Watanabe A, Nakamura K, Harada M Active and passive cutaneous anaphylaxis in WBB6F1 mouse, a mast cell-deficient strain. Immunol Invest 1990 19 227-233. 

The synthetic P-o-glucopyranoside 30 was converted to the cyanoglucoside rho-diocyanoside A (38a), which was isolated from the underground part of Rhodiola quadrifida (Pall.) Fisch. et Mey. (Crassulaceae) and found to show antiallergic activity in a passive cutaneous anaphylaxis test in rat. Acetylation of 30 gave an acetate (98% yield) which was subjected to ozonolysis to afford the aldehyde 39. The Horner-Emmons reaction of 39 using diethyl (l-cyanoethyl)phosphonate furnished (Z)-40a (32% yield from 30) and ( )-40b (10% yield from 30). The physical... 

PCA Passive cutaneous anaphylaxis pCDM8 Eukaryotic expression vector PCNA Proliferating cell nuclear antigen... 

Ovary, Z., Passive cutaneous anaphylaxis in immunological methods, in Council for International Organizations of Medical Sciences Symposium, Ackroid, J.F., ed., Blackwell Scientific Publications, Oxford, 1964, 259. 

Passive cutaneous anaphylaxis (PCA)-Test for potential antigenicity of compounds Other... 

Amino-substituted naphthoquinones and heterocyclic variants have been disclosed in the patent literature as 5-LO inhibitors. Compounds represented by (80) (X = C, N) from Lilly inhibited SRS-A release from sensitized guinea-pig lung tissue [218]. Similar compounds such as (81) (R = carboxylic ester, acyl, or aryl) and related naphthalene derivatives, from American Cyanamid, gave good inhibition in guinea-pig ISN (at 10 //g/ml) and in passive cutaneous anaphylaxis in mice (25-60 /zM i.p.) [219,220]. 

Li et al. (1994) examined the effects of chloroform administered in drinking water to guinea pigs with cedar pollen-induced allergic conjunctivitis, prepared by passive cutaneous anaphylaxis. Groups of 5 male... 

Passive cutaneous anaphylaxis studies of byssinotic and nonbyssinotic sera in our laboratory and similar studies in rabbits... 

There are four subclasses of IgG IgGi, 70% IgGj, 16% IgG., 10%, and IgG, 4%. IgGi is capable of inhibiting IgE-mediated passive cutaneous anaphylaxis (PGA) reaction in baboons when injected in relatively high concentrations. 

Passive cutaneous anaphylaxis inhibition. Acetone extract of the dried rhizome, administered intragastrically to rats at a dose of 200 mg/kg, was active vs IgE-sensitized animals . 

Hexahydropyrimido[l,2-a]azepin-4-ones 456, 463, and 467 display analgetic activity (77MI1). 10-Aminomethylene and 10-phenylhydrazino derivatives 478 (R = H) possess weak antiallergic effects in the passive cutaneous anaphylaxis (PCA) test (84JMC1253). 

Typical protocols for dermal sensitization, active systemic anaphylaxis, and passive cutaneous anaphylaxis tests are given in the article Animals in Drug Development, in this encyclopedia. In a typical gel-diffusion test, solutions of test compound, egg albumin (positive control), or vehicle (usually saline) are mixed with complete Freund s adjuvant. These mixtures are injected into animals (usually guinea pigs) of the... 

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