[Changes in the burrowing reflex of mice and rats under the influence of kynurenines]

Behaviour of SHR, C57B1/6 male mice and common albino male rats treated intracerebroventricularly or intraperitoneally with kynurenine, quinolinic, kynurenic, picolinic, xanthurenic, anthranilic acids and nicotinamide, was studied in the dark/light chamber. Quinolinic acid and its precursor kynurenine diminished dark preference, increased the number of transitions between dark and light compartments, diminished locomotion in light compartment. Biogenic amine phenylethylamine with its typical anxiogenic activity, exerted a similar action. Diazepam acted in the opposite way. Noncompetitive antagonist of the NMDA receptors, kynurenic acid, prevented the effect of quinolinic acid. The hole reflex appears to be a useful simple object to study neuroactive endogenous compounds on.