Variant angina and Samter's

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I found by chance this abstract, which says that some people have genetic thromboxane receptor defects, and that they are more likely to have aspirin-intolerant asthma. It does not say anything about any causality whatever behind the relationship, but it does mention the existence of thromboxane receptor antagonists and thromboxane synthase inhibitors, which may therefore be of some use against variant angina.-----------------------------Clin Exp Allergy. 2005 May;35(5):585-90. LinksAssociation of thromboxane A2 receptor gene polymorphism with the phenotype of acetyl salicylic acid-intolerant asthma.Kim SH, Choi JH, Park HS, Holloway JW, Lee SK, Park CS, Shin HD.Department of Allergy and Rheumatology, Ajou University School of Medicine, Suwon, Korea.BACKGROUND AND OBJECTIVE: The thromboxane A2 receptor (TBXA2R) is a receptor for a potent bronchoconstrictor, TBXA2 which is known to be related to bronchial asthma and myocardial infarction. TBXA2R antagonist and TBX synthase inhibitors have been found to be effective in the management of asthmatic patients. This study was aimed to evaluate whether genetic variants of TBXA2R may be related with development of acetyl salicylic acid (ASA)-intolerant asthma (AIA). METHODS: TBXA2R gene polymorphisms (TBXA2R+795T>C, TBXA2R+924T>C) were determined using a single-base extension method in 93 AIA patients compared with 172 patients with ASA-tolerant asthma (ATA) and 118 normal controls (NCs) recruited from the Korean population. HLA DPB1*0301 genotype was performed using a direct sequencing method. RESULTS: The rare C allele frequency of TBXA2R+795T>C was significantly higher in AIA than in ATA (P=0.03) and the TBXA2R+795T>C polymorphism was also associated with extent of percent fall in forced expiratory volume in 1 s (FEV1) after the inhalation of lysine-acetyl salicylic acid in AIA patients (P=0.009); AIA patients homozygous for the +795 C allele had a greater percent fall of FEV1 compared with individuals with TBXA2R+795 CT or TT genotypes. The frequency of patients carrying both the TBXA2R+795T>C rare allele and HLA DPB1(*)0301 was significantly higher in AIA patients (29.4%) than in ATA patients (7.3%) (P=0.008, odds ratio=5.3). CONCLUSION: These results suggest that the polymorphism of TBXA2R+795T>C may increase bronchoconstrictive response to ASA, which could contribute to the development of the AIA phenotype.