[The influence of docosahexaenoic acid and moderate perinatal hypoxia on the performance of one-month-old Wistar rats in a T-maze test].

BACKGROUND

Docosahexaenoic acid (DHA) has been shown to improve neurodevelopment in both human observations and animal models. Perinatal hypoxic insults have been recognized as a major cause of neurodevelopmental disturbances.

OBJECTIVE

To find out if the CNS-improving effect of DHA could be induced in animals subjected to mild perinatal hypoxic conditions.

METHODS

A total of 140 Wistar rat pups were separated into two main groups of 70 each, and one group was reared on a DHA-supplemented diet while the other was not. One half of each group was subjected to immediate post-natal hypoxia (FiO2 = 0.05, 1 h). All the rats were individually subjected to a T-maze to test their passive-avoidance performance, among other skills, on days P25 (three trials) and P30 (one trial). All the trials were videotaped and reviewed to record the maze-solving time (MST), the number of electrical hazards (NEH) and the correct maze-solution percentage (CMS).

RESULTS

The animals in the control group significantly improved their MST (p < 0.01). The group on the DHA-supplemented diet improved only the CMS (p < 0.001). The hypoxic group improved the MST (p < 0.014) and the NEH (p < 0.004). The hypoxic group on the DHA-supplemented diet improved the NEH (p < 0.0000) and the CMS (p < 0.0001).

CONCLUSIONS

The subgroups subjected to one experimental condition or the other (DHA-supplemented diet or perinatal hypoxia) independently improved their T-maze-test performance more than the absolute control group. The rats subjected to both conditions appeared to improve their T-maze-test solution performance more effectively than the control groups and the groups subjected to only one of the two conditions.