Fig. 2: Rapid homeostatic plasticity elicited by ketamine and retinoic acid.

Preclinical studies have demonstrated that both ketamine and retinoic acid can elicit a rapid form of homeostatic plasticity. Ketamine and retinoic acid have been also shown to trigger a rapid antidepressant-like effect in animal models. Left: Field excitatory postsynaptic potentials (fEPSPs) in 20 μM ketamine-treated wild type and RARα-knock-out hippocampal slices. Initial field potential (FP) slopes were plotted as a function of time. Inset, representative wave forms from wild type and RARα-knock-out slices before and after 30 min. rapid treatment. Right: fEPSPs were recorded from wild type hippocampal slice treated with AM580, a RARα agonist, in the presence or absence of ketamine pretreatment. After 20 min of stable baseline measurement, 20 μM ketamine or vehicle were applied for 30 min. After these pretreatments, 20 μM AM580 was applied for 2 h and then fEPSP responses were recorded for 20 min. Note that effects of ketamine and AM580 treatments occlude each other suggesting a common endpoint. Inset, representative wave forms before and after treatment (Modified from [58]).