High corticosterone levels in prenatally stressed rats predict persistent paradoxical sleep alterations.
Prenatal stress predisposes rats to long-lasting disturbances that persist throughout adulthood (e.g., high anxiety, dysfunction of the hypothalamo-pituitary-adrenal axis, and abnormal circadian timing). These disturbances parallel to a large extent those found in depressed patients, in which hypercortisolemia and sleep alterations may be related to stress-inducing events. We studied sleep-wake parameters in control and prenatally stressed adult rats (3-4 months old) and examined possible relationships with their corticosterone levels (determined at 2 months of age). Under baseline conditions, prenatally stressed rats showed increased amounts of paradoxical sleep, positively correlated to plasma corticosterone levels. Other changes include increased sleep fragmentation, total light slow-wave sleep time, and a slight decrease in the percentage of deep slow-wave sleep relative to total sleep time. During recovery sleep from acute restraint stress, all sleep changes persisted and were correlated with stress-induced corticosterone secretion. High corticosterone levels under baseline conditions as well as an acute stress challenge may thus predict long-term sleep-wake alterations in rats. Taken together with other behavioral and hormonal abnormalities in prenatally stressed animals, the pronounced changes in sleep-wake parameters that are similar to those found in depressed patients suggest that prenatal stress may be a useful animal model of depression.
Dugovic
C
C
Department of Neuropsychopharmacology, Janssen Research Foundation, 2340 Beerse, Belgium.
Maccari
S
S
Weibel
L
L
Turek
F W
FW
Van Reeth
O
O
D000704:Analysis of Variance; D000818:Animals; D001007:Anxiety / Q000503:physiopathology*; D003345:Corticosterone / Q000097:blood / Q000378:metabolism*; D004569:Electroencephalography; D005260:Female; D011247:Pregnancy; D011248:Pregnancy Complications / Q000523:psychology*; D011297:Prenatal Exposure Delayed Effects; D051381:Rats; D017207:Rats, Sprague-Dawley; D012044:Regression Analysis; D012149:Restraint, Physical; D012895:Sleep, REM / Q000502:physiology*
D003345:Corticosterone