Behavioural alteration in the progeny of rats exposed to ketamine, a n-methyl-d-aspartate receptor blocker
The first study was conducted with the administration of ketamine to rats during pregnancy, both pregnancy and lactation, or lactation, respectively, in order to localisc the most sensitive period for behavioural effects of ketamine. In the second study, pups were injected subcutaneously with ketmnine during the suckling period. No significant effects on litter size, physical signs. early movements and neuromuscular development of the pups were observed. From the discrimination behavioural tests in Skinner boxes differences between groups appeared at the most demanding tasks, the 10 % reinforcement schedule. In the first study, the behavioural activity as expressed by the total number of tray visits tended to be increased in the preg/lae group, although not statistically significant. For the animals exposed during lactation (lac) and especially those exposed during pregnancy and lactation (preg/lae), the percentage of correct tray visits tended to be decreased during the last 5 sessions.
In the second study, the total activity as expressed by total number of lever presses tended to be increased in the in pups exposed by postnatal injections (inj), although not statistically significant. In the same group the percentage of correct lever presses tended be decreased during the last 5 sessions. For the perseveration error type, there was a statistically significant increase in error number for the last 5 sessions in the injected (inj) group. Reduced learning ability was observed both for the pups that were indirectly exposed to ketamine both prenatally and during lactation, and for the pups receiving direct ketamine injections during the suckling period, more clearly however in the latter group.