Long lasting sex-specific effects upon behavior and S100b levels after maternal separation and exposure to a model of post-traumatic stress disorder in rats.
This study was undertaken to verify if repeated long-term separation from dams would affect the development of parameters related to post-traumatic stress disorder (PTSD) after animals are subjected to inescapable shock when adults. Wistar rats were subjected to repeated maternal separation during post-natal days 1-10. When adults, rats from both sexes were submitted to a PTSD model consisting of exposure to inescapable footshock, followed by situational reminders. We observed long-lasting effects of both interventions. Exposure to shock increased fear conditioning. Anxiety-like behavior was increased and exploratory activity decreased by both treatments, and these effects were more robust in males. Additionally, basal corticosterone in plasma was decreased, paralleling effects observed in PTSD patients. Levels of S100B protein in serum and cerebrospinal fluid (CSF) were measured. Levels in serum correlated with the effects observed in anxiety-like behavior, increasing in males exposed to shock, and presenting no effect in females. S100B in CSF was increased in females submitted to maternal separation during the neonatal period. These results suggest that, in rats, an early stress experience such as maternal separation may aggravate some effects of exposure to a stressor during adult age, and that this effect is sex-specific. Additionally, data suggest that the increased S100B levels, observed in serum, have an extracerebral origin, possibly mediated by an increase in the noradrenergic tonus. Increased S100B in brain could be related to its neurotrophic actions.
Diehl
Luisa Amalia
LA
Departamento de Bioquímica, ICBS, Universidade Federal do Rio Grande do Sul, Ramiro Barcelos, 2600, Anexo, Lab. 11. 90035-003 - Porto Alegre, RS, Brazil.
Silveira
Patrícia Pelufo
PP
Leite
Marina C
MC
Crema
Leonardo Machado
LM
Portella
Andre Krumel
AK
Billodre
Mauro Nör
MN
Nunes
Edelvan
E
Henriques
Thiago P
TP
Fidelix-da-Silva
Linda Brenda
LB
Heis
Marta D
MD
Gonçalves
Carlos Alberto
CA
Quillfeldt
Jorge Alberto
JA
Dalmaz
Carla
C
D000704:Analysis of Variance; D000818:Animals; D000831:Animals, Newborn; D001522:Behavior, Animal / Q000502:physiology*; D003213:Conditioning, Psychological / Q000502:physiology; D003345:Corticosterone / Q000097:blood; D004195:Disease Models, Animal; D004597:Electroshock / Q000009:adverse effects; D005106:Exploratory Behavior / Q000502:physiology; D005239:Fear / Q000502:physiology; D005260:Female; D008297:Male; D008426:Maternal Deprivation; D009414:Nerve Growth Factors / Q000378:metabolism*; D011247:Pregnancy; D051381:Rats; D017208:Rats, Wistar; D064568:S100 Calcium Binding Protein beta Subunit; D009418:S100 Proteins / Q000378:metabolism*; D012727:Sex Characteristics; D013313:Stress Disorders, Post-Traumatic / Q000378:metabolism*
D009414:Nerve Growth Factors; D064568:S100 Calcium Binding Protein beta Subunit; D009418:S100 Proteins; C579158:S100b protein, rat; D003345:Corticosterone