By removing the escape box at the end of the training
period we introduced the PT in our variant of the test,
which enabled us to assess memory-dependent and independent
parameters as well as recent (PT1) and longerterm
(PT2) retention of spatial memory, whose magnitude
is proportional to the inverse of spatial memory extinction.
The moderate deterioration in recent (PT1) and longerterm
(PT2) spatial memory retention, as assessed by
latency to escape hole and number of errors, revealed
by our study is in line with PT in MWM studies in young
(3 months) and middle-aged (12 months) male SD rats
where no significant age differences were detected either
in platform trials (using swim time and swim distance
measures) and in the one-probe trial measure (percent
of swim path spent in the correct quadrant). However,
the 12-month-old rats were impaired on the platform
crossings measure during the probe trial