Physiological effects of trypan blue on chick embryos

Abstract

Ten-day chick embryos (1) received yolk sac injections of 0.1 ml of 1.5% trypan blue in sterile saline, (2) received 0.1 ml of sterile saline or ( 3 ) were handled and returned to the incubator and examined five hours later. Trypan blue treated embryos exhibited decreased survival rate and significant decreases in plasma glucose, chloride, Con content and blood pH. Plasma potassium and embryonic wet weight were significantly elevated, but little change occurred in plasma sodium or hematocrit. Embryos frequently exhibited hemorrhaging after treatment. Saline treatment caused a small but significant decrease in plasma chloride and only a slight decrease in survival rate.The immediate response to trypan blue was markedly similar to that of hypoxia, presenting additional evidence in support of the view that trypan blue may interfere with the normal oxygen consumption of the embryo.

Using Chicken Embryos for Teratology Studies

“…The embryo will start to develop as soon as the egg is incubated, even somewhat at room temperature. A number of researchers (Hoffman and Ramm, , ; Hoffman, ; Hoffman and Campbell, ; Brunstrom, , ; Brunstrom and Darnerud, ; Brunstrom and Lund, ; Powell et al, , ; Grasman and Whitacre, ; Fox and Grasman, ) prefer to start incubating the egg first, then injecting the toxicant at embryonic day 3 or 4. This way, researchers can candle the eggs prior to injection and cull out any eggs that do not seem to be developing normally.…”

“…In the past few decades, several groups of investigators began using the chicken embryo as a model for toxicant‐induced teratological studies. Hoffman and colleagues (Hoffman and Ramm, , ; Hoffman, ; Hoffman and Campbell, ) used the chicken embryo to study chemical‐induced teratogenity in a large number of studies that evaluated the teratogenic potency of a broad range of pollutants. Jelinek and colleagues (Jelinek and Marhan, ) developed the CHick Embryotoxicity Screening Test (CHEST) to evaluate pharmacological agents with respect to regulatory rat‐rabbit procedures.…”