title: Therapeutic drugs that slow the heart rate of early rat embryos. Is there a risk for the human?
abstract: During the organogenic period of development the cardiovascular system of the embryo fulfills several functions including delivery of oxygen and nutrients and a hemodynamic role necessary for cardiac morphogenesis, angiogenesis and hematopoiesis. It is expected that at each stage of embryonic development there is an ideal embryonic heart rate and contractility that maintains the optimal blood flow and pressure to fulfill these various functions. In vitro rat embryo culture studies have revealed that many therapeutic drugs (antiarrhythmics, antidepressants, antipsychotics and anticonvulsants), that may be taken during human pregnancy, cause a concentrationdependent slowing of the embryonic heart and irregular heart rate at higher concentrations. The concentrations causing bradycardia in vitro are often close to human therapeutic plasma concentrations and raise concern that these drugs can potentially cause embryonic death or malformations, and that current reproductive toxicity testing does not adequately examine possible effects of drugs on the embryo's cardiac function.
authors: William S
authors: WS
authors: Webster
authors: Mats
authors: M
authors: Nilsson
authors: Discipline of Anatomy and Histology, Sydney Medical School, University of Sydney, Sydney, NSW 2006, Australia. bill.webster@sydney.edu.au.
authors: Helen
authors: H
authors: Ritchie
mesh_terms: D000818:Animals; D001919:Bradycardia / Q000139:chemically induced* / Q000196:embryology*; D002316:Cardiotonic Agents / Q000009:adverse effects; D064420:Drug-Related Side Effects and Adverse Reactions; D047108:Embryonic Development / Q000187:drug effects* / Q000502:physiology; D005260:Female; D006339:Heart Rate / Q000187:drug effects* / Q000502:physiology; D006801:Humans; D011247:Pregnancy; D051381:Rats; D012307:Risk Factors
chemical_list: D002316:Cardiotonic Agents