title: The Effects of Beta Amyloid Peptide 1-42 on Isolated Rat Hearts and Ileum Smooth Muscle.
abstract: Neurotoxic beta amyloid peptides (βAPs) are involved in the pathogenesis of Alzheimer disease. βAP1-42 may also play a role in the regulation of cardiovascular functions. Therefore, we investigated the possible effects of βAP1-42 on isolated rat heart and ileum. The hearts were perfused with modified Krebs-Henseleit solution. Left ventricular developed pressure (LVDP), maximal rate of pressure development of left ventricle (+dP/dtmax), heart rate, coronary flow, monophasic action potential amplitude (MAPamp), MAP duration at 90% repolarization (MAP90) and contractions of ileum were measured. One, 10 and 100 nmol/l doses of βAP1-42 significantly decreased LVDP, +dP/dtmax and heart rate. The dose of 1 nmol/l did not change coronary flow, but 10 and 100 nmol/l doses significantly reduced it. All doses of βAP1-42 did not alter MAPamp, but increased MAP90. βAP1-42 (1, 10, 100, 1,000 nmol/l) also did not influence ileum contractions. We suggest that βAP1-42 produces negative inotropic and negative chronotropic effects with an increase in MAP duration. Furthermore, βAP1-42 at high doses decreases coronary flow.
authors.affiliation: Department of Physiology, Faculty of Medicine, Eskisehir Osmangazi University, Eskisehir, Turkey.
authors.forename: Neda
authors.initials: N
authors.lastname: Yousefirad
authors.forename: Ziya
authors.initials: Z
authors.lastname: Kaygisiz
authors.forename: Yasemin
authors.initials: Y
authors.lastname: Aydin
mesh_terms: D016229:Amyloid beta-Peptides / Q000633:toxicity*; D000818:Animals; D004305:Dose-Response Relationship, Drug; D005260:Female; D006321:Heart / Q000187:drug effects* / Q000502:physiology; D006339:Heart Rate / Q000187:drug effects / Q000502:physiology; D007082:Ileum / Q000187:drug effects* / Q000502:physiology; D009130:Muscle, Smooth / Q000187:drug effects* / Q000502:physiology; D009924:Organ Culture Techniques; D010446:Peptide Fragments / Q000633:toxicity*; D051381:Rats; D017207:Rats, Sprague-Dawley
chemical_list: D016229:Amyloid beta-Peptides; D010446:Peptide Fragments; C075222:amyloid beta-protein (1-42)