Cardiac chronotropic hypo-responsiveness and atrial fibrosis in rats chronically treated with lithium

• Published in: Autonomic neuroscience 2019-01, Vol.216, p.46-50
• Main Authors: Moradi, Somayeh, Aminian, Atefeh, Abdollahi, Alireza, Jazayeri, Amin, Ghamami, Giti, Nikoui, Vahid, Bakhtiarian, Azam, Jazaeri, Farahnaz
• Format: Article
• Language: English
• Subjects: Animals; beta-Arrestin 2 - biosynthesis; Bipolar disorder; Cardiac fibrosis; Chronotropic response; Collagen Type I - biosynthesis; Depression, Chemical; Fibrosis - chemically induced; Fibrosis - pathology; Gene Expression - drug effects; Heart Atria - drug effects; Heart Atria - metabolism; Heart Atria - pathology; Heart Rate - drug effects; Lithium; Lithium Chloride - adverse effects; Lithium Chloride - blood; Male; Rats; Thiophenes - pharmacology; β-Arrestin
• ISSN: 1566-0702; 1872-7484
• DOI: 10.1016/j.autneu.2018.09.002

Lithium is a widely used mood-stabilizing agent; however, it causes a variety of cardiovascular side effects including sinus node dysfunction. In this study we explored the potential adverse effects of lithium on cardiac chronotropic responsiveness, atrial tissue histology and gene expression in rats that were chronically treated with therapeutic doses of lithium. Male Wistar albino rats were given lithium chloride (2.5 g/kg) orally for 2 or 3 months. Following treatment, the atria were isolated and spontaneously beating rate and chronotropic responsiveness to β-adrenergic stimulation was evaluated in an organ bath. Development of cardiac fibrosis was examined by histological methods. The expression of atrial Col1a1 (collagen I, alpha 1) and β-arrestin2 was also assessed using quantitative RT-PCR. Treatment with lithium induced a significant hypo-responsiveness to adrenergic stimulation (P