@article{oai:niigata-u.repo.nii.ac.jp:00016491, author = {柴, 正美}, issue = {8}, journal = {新潟医学会雑誌, 新潟医学会雑誌}, month = {Aug}, note = {Abnormal genes were reported in the idiopathic long QT syndrome (LQT) but the pathogenesis and the aggravating factors of the QT interval on the occurrence of life-threatening ventricular tachyarrythmias are to be determined. Following a case report in which intracoronary acetylcholine (ACh) induced QT prolongation, the effect of Ach on the QT interval was studied. QTc interval was significantly prolonged by ACh:0.519±0.029 sec^<1/2> to 0.688±0.067 sec^<1/2> in QT syndrome but not in the healthy control group. We, then, analyzed the gene of G protein in the blood samples from the patients with LQT using RT-PCR followed by direct nucleotide sequencing. One of 12 patients had 129 bp deletion in G protein β3 subunit. Another patient had four point mutations. They showed C to T transition at codon 12, G to T transition at codon 27, C to T transition at codon 53 and C to T transition at codon 60, which substituted cystein (TGC) for arginine (CGC), asparagine (AAT) for lysine (AAG), leucine (CTA for prorine (CCA) and tryptophan (TGG) for arginie (CGG), respectively. Though these changes suspected splicing abnormality and polymorphysm, analysis of the qene of G protein needs to be studied further in a large number of patients with LQT.}, pages = {465--476}, title = {特発性QT延長症候群における冠動脈内アセチルコリン投与試験および三量体GTP結合タンパク遺伝子の解析}, volume = {112}, year = {1998} }