Learning activity induces rapid generation of formaldehyde
To investigate the role of brain formaldehyde in cognitive processes, we examined whether hippocampal formaldehyde concentration changes after spatial learning activity in Morris water maze (MWM) in the wild-type adult male Sprague−Dawley (SD) rats. First, we observed that healthy rats exhibited a rapid reduction in escape latency during training and significantly greater time spent in the target quadrant compared to nontarget quadrants during the probe test (Fig. 1a, b), suggesting that a classical spatial memory was forming in these rats. Notably, this spatial learning was associated with a marked increase in hippocampal formaldehyde as detected using a free formaldehyde-sensitive fluorescent probe NaFA19 (Fig. 1c). The magnitude of this elevation was ~30 μM on day 1 and ~50 μM on day 6 as quantified by…
