Boardman et al. exposed the specimens of the caterpillar Pyrrharctiais abella to various sub-zero temperatures for up to 6 weeks to investigate the effect of cold intensity and duration on ion redistribution upon thawing. The
ions Na+, K+, Mg2+ and Ca2+ selleck were measured after thawing in the haemolymph, fat body, muscle, midgut tissue and hindgut tissue. Both ion content and water distribution changes were observed after thawing, with the largest effect seen in the fat body and midgut tissue. The observations during this study led the authors to conclude that failure to regain ion homeostasis after thawing is implicated in the mortality of freeze tolerant insects. J. Williams and R.E. Lee investigated the effect of extracellular freezing and dehydration on the haemolymph volume, and cryoprotectant and ion levels in the haemolymph in larvae of the goldenrod gall fly Eurosta solidaginis. The authors observed that dehydrated larvae, or ones that had been frozen at −5 or −20 °C, had a significantly smaller proportion of their body water as haemolymph Rapamycin clinical trial compared to the controls. Haemolymph and intracellular content of ions remained largely unchanged between treatment groups. Larvae exposed to dehydration and freezing at −20 °C had a much lower relative amount of cryoprotectants in the haemolymph compared to the controls. From the
present study the authors conclude that E. solidaginis larvae likely maintained cellular water volume during dehydration and freezing by moving solutes from their haemolymph into intracellular compartments. Cryoprotectants did appear to move into the intracellular
compartment during both dehydration and freezing. The authors suggest that the correlation between reduced haemolymph volume and intracellular movement of cryoprotectants may represent a link between tolerance of dehydration and cold in E. solidaginis larvae. A list of the most important papers by Karl Erik Zachariassen Aarset, A.V., Zachariassen, K.E., 1982. Effects of oil pollution on the freezing tolerance and solute concentration of the blue mussel Mytilus edulis. Marine Biology 72, 45–51. Baust, J.G., Zachariassen, K.E., 1983. Seasonally active cell matrix clonidine associated ice nucleators in an insect. Cryo-Letters 4, 65–71. Bjerke, R., Zachariassen, K.E., 1997. Effects of dehydration on water content, metabolism, and body fluid solutes of a carabid beetle from dry savanna in East Africa. Comparative Biochemistry and Physiology A 118, 779–787. Børseth, J.F., Aunaas, T., Denstad, J.P., Nordtug, T., Olsen, A.J., Schmid, R., Skjaervo, G., Zachariassen, K.E., 1995. Transmembrane sodium energy gradient and calcium content in the adductor muscle of Mytilus edulis L. in relation to the toxicity of oil and organic-chemicals. Aquatic Toxicology 31, 263–276. Børseth, J.F., Aunaas, T., Einarson, S., Nordtug, T., Olsen, A.J., Zachariassen, K.E., 1992. Pollutant-induced depression of the transmembrane sodium-gradient in muscles of mussels.