Feeding impairs chill coma recovery in the migratory locust (Locusta migratoria)

J Insect Physiol. 2013 Oct;59(10):1041-8. doi: 10.1016/j.jinsphys.2013.07.008. Epub 2013 Aug 8.


Low temperature causes loss of neuromuscular function in a wide range of insects, such that the animals enter a state known as chill coma. The ability to recover from chill coma (chill coma recovery time) is often a popular phenotype to characterise chill tolerance in insects. Chill coma in insects has been shown to be associated with a decrease in haemolymph volume and a marked increase in [K(+)], causing dissipation of K(+) equilibrium potential and resting membrane potential. High potassium diet (wheat) has also previously been shown to increase haemolymph [K(+)] in Locusta migratoria leading to sluggish behaviour. The present study combined these two independent stressors of ion and water homeostasis, in order to investigate the role of K(+)- and water-balance during recovery from chill coma, in the chill sensitive insect L. migratoria. We confirmed that cold shock elicits a fast increase in haemolymph [K(+)] which is likely caused by a water shift from the haemolymph to the muscles and other tissues. Recovery of haemolymph [K(+)] is however not only reliant on recovery of haemolymph volume, as the recovery of water and K(+) is decoupled. Chill coma recovery time, after 2h at -4 °C, differed significantly between fasted animals and those fed on high K(+) diet. This difference was not associated with an increased disturbance of haemolymph [K(+)] in the fed animals, instead it was associated with a slowed recovery of muscle [K(+)], muslce water, haemolymph [Na(+)] and K(+)equilibrium potential in the fed animals.

Keywords: Cold coma; Cold tolerance; Ion transport; Nernst potential; Sodium balance; Stress resistance.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Cold Temperature
  • Cold-Shock Response*
  • Diet
  • Female
  • Hemolymph / metabolism*
  • Locusta migratoria / physiology*
  • Male
  • Potassium / metabolism*
  • Water-Electrolyte Balance*


  • Potassium