The effect of cooling rate and temperature on the toxicity of ethylene glycol in the rabbit internal carotid artery.
The smooth muscle and vascular endothelium of small elastic arteries (the rabbit common carotid artery) are injured by exposure to 40% ethylene glycol (EG) at 4 degrees C, and additional damage occurs when the arteries are cooled without freezing to -20 degrees C. This paper reports attempts to reduce this injury by altering the cooling rate and temperature of exposure to the cryoprotectant. Very slow cooling (0.1 degree C/min) removed all residual smooth muscle and endothelial function when assessed in vitro after rewarming and removal of the cryoprotectant. Very rapid cooling to -20 degrees C also increased the injury, both to the endothelium and to the smooth muscle. Reducing the temperature of exposure to 40% EG from +4 degrees C to -20 degrees C had no beneficial effect on the smooth muscle but enabled the vascular endothelium to retain some functional activity. These data suggest that the mechanism responsible may be related to the physical properties of ethylene glycol rather than to a biochemical interaction with metabolic processes, and that it is a mechanism which is highly specific for the cell types involved. It also underlines the difficulties involved in the successful cryopreservation of complex tissues and organs.
Wusteman
M
M
Department of Biology, University of York, United Kingdom.
Boylan
S
S
Pegg
D E
DE
D000818:Animals; D020212:Carotid Artery Injuries; D002343:Carotid Artery, Internal / Q000187:drug effects* / Q000502:physiology; D015925:Cryopreservation / Q000379:methods*; D004730:Endothelium, Vascular / Q000187:drug effects / Q000293:injuries / Q000502:physiology; D019855:Ethylene Glycol; D005026:Ethylene Glycols / Q000633:toxicity*; D066298:In Vitro Techniques; D009131:Muscle, Smooth, Vascular / Q000187:drug effects / Q000293:injuries / Q000502:physiology; D011817:Rabbits; D013696:Temperature; D013997:Time Factors; D014661:Vasoconstriction
D005026:Ethylene Glycols; D019855:Ethylene Glycol