Figure 1.

Effect of Li⁺ (126 mM) on spontaneous inhibitory postsynaptic currents (sIPSCs) on hypothalamic preoptic area (hPOA) neurons. (A) A representative current trace of sIPSCs recorded in the presence of Na⁺ and Li⁺ artifical cerebrospinal fluid (ACSF) on hPOA neurons at a holding potential of −60 mV. (a₁–a₃), sections of the current trace in Figure 1A show sIPSCs before, during, and after perfusion of Li⁺ at 2 s intervals, respectively. (B) A spike frequency histogram (bin size 10 s) of current traces in Figure 1A. (C) A cumulative probability plot of sIPSCs inter-event interval (IEI) in the presence of Na⁺ (solid line) and Li⁺ (dotted line). Note that the cumulative probability curve was left-shifted by Li⁺_, indicating the increase of sIPSCs frequency (Kolmogorov-Smirnov test, p < 0.05). (D) Mean relative amplitude and frequency of sIPSCs in LiCl ACSF compared to NaCl ACSF (** p < 0.01 by a paired t-test).