Fig. 4. Model of the hypothermia response seen in rat brain glial cells. Hypothermia inhibits the Na⁺/K⁺-ATPase and also upsets the normal balance between Na⁺ influx and K⁺ efflux in favour of Na⁺ influx. This leads to a net accumulation of Na⁺ that is exacerbated by hypothermia-induced activation of the Na⁺/H⁺ exchanger, leading to cell swelling (redrawn in part from Plesnila et al., 2000, with permission of Cambridge University Press). Further details are given in the text.