Rapid eye-movement sleep deprivation does not ‘rescue’ developmentally regulated long-term potentiation in visual cortex of mature rats

Abstract

The age at which it is possible to obtain a usually age-limited (developmental) form of long-term potentiation (LTP) in rat visual cortex slices can be extended by suppressing rapid eye movement (REM) sleep. In this study, we examined whether REM sleep deprivation can also ‘rescue’ this type of LTP in older rats. Rats, 42–59 days of age, were either REM sleep-deprived for 7–10 days ( n=8), or not deprived of REM sleep (control group, n=8). Brain slices from visual cortex were tested for the developmental form- and a related, non-developmental form of LTP. Three of the eight REM sleep-deprived animals and four of the eight non-deprived animals met criteria for a valid attempt to induce the developmental form of LTP. Though the non-age-regulated form of LTP could be obtained in all seven of these animals, the developmental form could not be elicited in any, indicating that REM sleep deprivation does not uniformly affect all forms of LTP in adult rats. We conclude that extended periods of REM sleep deprivation do not facilitate induction of developmentally regulated LTP once the animal is beyond a certain age.