The effects of moderate hypoxia and moderate hypoxia plus hypercapnea on cardiac development in chick embryos

Abstract

Moderate hypoxia (5% 0,) and moderate hypoxia + hypercapnea (5% 0 2 + 2 % C02) administered to Hamilton-Hamburger stage17 (60-h) chick embryos produced significant frequencies of brain, eye, and limb malformations, as observed grossly, and cardiovascular malformations, as found in serial sections. Hypoxia f hypercapnea was more lethal (survival rate, 49%) than hypoxia alone (mean survival rate, 6 5 % ) but the frequencies of malformations produced by both procedures were in the same range. When moderate hypoxia + hypercapnea was utilized hemorrhages, heart and blood vessel distention, bradycardia, and the disappearance of blood-flow patterns occurred. Such changes were previously found to be produced by moderate hypoxia alone. Since cardiovascular malformations were produced under conditions known to affect hemodynamics, it is postulated that these events are related.

The role of embryology in teratological research, with particular reference to the development of the neural tube and heart

“…Examples of morphological changes which are almost certainly brought about in this way are the development of the spiral septum in the arterial outflow region of embryonic heart, and, much later, the considerable circulatory changes which take place within the heart and in the circulation at birth. Indeed, temporary, reversible changes in the haemodynamic equilibrium which have been induced by hypoxia have been shown to result in the production of malformations of the heart in the chick embryo (Jaffee, 1974).…”

Hypoxia induces cardiac malformations via A1 adenosine receptor activation in chicken embryos

“…Hypoxia exposure during critical periods of embryogenesis can lead to impaired heart development including cardiac bifida, as well as neural tube and somite defects (Altimiras and Phu, 2000; Chan and Burggren, 2005; Jaffee, 1974; Villamor et al, 2004). Our recent studies show that a period of transient hypoxia during early murine embryogenesis impairs cardiac development and leads to intrauterine growth retardation (Wendler et al, 2007).…”

Impact of Hypoxia on Early Chick Embryo Growth and Cardiovascular Function

“…O xygen tension is a critical determinant of appropriate embryonic and fetal development (1)(2)(3)(4)(5)(6)(7), and hypoxia is associated with increased fetal mortality. Specifically, hypoxia is known to cause decreased birth weight, cerebrovascular anomalies, CV dysfunction, and altered angiogenesis (2-6), with hypoxia producing greater negative effects later in gestation (7).…”