title: Immunohistochemistry of connexin43 and zonula occludens-1 in the myocardium as markers of early ischemia in autopsy material.
abstract: Immunohistochemistry of the terminal complement complex (C5b-9) and fibronectin (FN) is useful to detect myocardial ischemia preceding necrosis in the postmortem diagnosis of sudden cardiac death. The present immunohistochemical study examined connexin43 (Cx43) and zonula occludens-1 (ZO-1) as markers of early myocardial ischemia in addition to the above-mentioned markers, using forensic autopsy cases of acute deaths due to myocardial infarction (MI, n=15) and acute ischemic heart disease (AIHD) without apparent myocardial necrosis (n=8), compared with those of acute mechanical asphyxiation (As, n=24) and drowning (D, n=10) as controls. Immunopositivities of each marker in the myocardium were semi-quantitatively graded by scoring. ZO-1, C5b-9 and FN were detected in the myocardial cytoplasm, whereas Cx43 and non-phosphorylated (np) Cx43 showed varied localizations at the intercalated disc, in the cytoplasm and along the lateral cell border. ZO-1 and FN showed a tendency to be detected more intensely in MI and IHD than in As and D. C5b-9 showed specific staining at the site of ischemia in MI (n=10/15) and AIHD (n=6/8), while the distribution of npCx43 was different in most cases of MI (n=14/15) and AIHD (n=5/8), compared with As and D; npCx43 positivity score was higher in the cytoplasm than at the intercalated disc, indicating redistribution due to myocardial ischemia. Such findings were detected in a few cases of As (n=3/24). These findings suggest that the combination of npCx43 and C5b-9 immunohistochemistry is useful for detecting early lesions of myocardial ischemia in sudden cardiac death.
authors.affiliation: Department of Legal Medicine, Osaka City University Medical, School, Osaka, Japan. m2071101@med.osaka-cu.ac.jp.
authors.forename: Osamu
authors.initials: O
authors.lastname: Kawamoto
authors.affiliation: Department of Legal Medicine, Osaka City University Medical, School and Forensic Autopsy Section, Medico-legal Consultation and Postmortem Investigation Support Center (MLCPI-SC), Osaka, Japan.
authors.forename: Tomomi
authors.initials: T
authors.lastname: Michiue
authors.affiliation: Department of Legal Medicine, Osaka City University Medical, School and Forensic Autopsy Section, Medico-legal Consultation and Postmortem Investigation Support Center (MLCPI-SC), Osaka, Japan.
authors.forename: Takaki
authors.initials: T
authors.lastname: Ishikawa
authors.affiliation: Department of Legal Medicine, Osaka City University Medical, School and Forensic Autopsy Section, Medico-legal Consultation and Postmortem Investigation Support Center (MLCPI-SC), Osaka, Japan.
authors.forename: Hitoshi
authors.initials: H
authors.lastname: Maeda
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001344:Autopsy; D015415:Biomarkers / Q000378:metabolism; D002423:Cause of Death; D015938:Complement Membrane Attack Complex / Q000378:metabolism; D018031:Connexin 43 / Q000378:metabolism*; D016757:Death, Sudden, Cardiac / Q000473:pathology*; D005260:Female; D005353:Fibronectins / Q000378:metabolism; D006801:Humans; D007150:Immunohistochemistry; D008297:Male; D008875:Middle Aged; D017202:Myocardial Ischemia / Q000175:diagnosis* / Q000378:metabolism / Q000473:pathology; D009206:Myocardium / Q000378:metabolism* / Q000473:pathology; D010766:Phosphorylation; D019108:Tight Junctions / Q000378:metabolism; D055815:Young Adult; D062826:Zonula Occludens-1 Protein / Q000378:metabolism*
chemical_list: D015415:Biomarkers; D015938:Complement Membrane Attack Complex; D018031:Connexin 43; D005353:Fibronectins; D062826:Zonula Occludens-1 Protein