title: Association between Na⁺,K⁺-ATPase activity and the vulnerability/resilience to mood disorders induced by early life experience.
abstract: There is increasing evidence that early life events can influence neurodevelopment and later susceptibility to disease. Chronic variable stress (CVS) has been used as a model of depression. The objective of this study was to evaluate the interaction between early experience and vulnerability to chronic variable stress in adulthood, analyzing emotional, metabolic and neurochemical aspects related to depression. Pups were (1) handled (10 min/day) or (2) left undisturbed from day 1 to 10 after birth. When the animals reached adulthood, the groups were subdivided and the rats were submitted or not to CVS, which consisted of daily exposure to different stressors for 40 days, followed by a period of behavioral tasks, biochemical (plasma corticosterone and insulin sensitivity) and neurochemical (Na⁺,K⁺-ATPase activity in hippocampus, amygdala and parietal cortex) measurements. Neonatally-handled rats demonstrated shorter immobility times in the forced swimming test, independently of the stress condition. There was no difference concerning basal corticosterone or insulin sensitivity between the groups. Na⁺,K⁺-ATPase activity was decreased in hippocampus and increased in the amygdala of neonatally-handled rats. CVS decreased the enzyme activity in the three structures, mainly in the non-handled group. These findings suggest that early handling increases the ability to cope with chronic variable stress in adulthood, with animals showing less susceptibility to neurochemical features associated with depression, confirming the relevance of the precocious environment to vulnerability to psychiatric conditions in adulthood.
authors.affiliation: PPG Neurociências, Instituto de Ciências Básicas da Saúde (ICBS), Universidade Federal do Rio Grande do Sul, Porto Alegre, Rio Grande do Sul, Brazil. 00032386@ufrgs.br
authors.forename: Patrícia Pelufo
authors.initials: PP
authors.lastname: Silveira
authors.forename: André Krumel
authors.initials: AK
authors.lastname: Portella
authors.forename: Carla da Silva
authors.initials: Cda S
authors.lastname: Benetti
authors.forename: Alexandra Ioppi
authors.initials: AI
authors.lastname: Zugno
authors.forename: Emilene Barros da Silva
authors.initials: EB
authors.lastname: Scherer
authors.forename: Cristiane Bastos
authors.initials: CB
authors.lastname: Mattos
authors.forename: Angela T S
authors.initials: AT
authors.lastname: Wyse
authors.forename: Aldo Bolten
authors.initials: AB
authors.lastname: Lucion
authors.forename: Carla
authors.initials: C
authors.lastname: Dalmaz
mesh_terms: D000223:Adaptation, Psychological; D000679:Amygdala / Q000378:metabolism; D000818:Animals; D000831:Animals, Newborn; D001786:Blood Glucose / Q000378:metabolism; D003345:Corticosterone / Q000097:blood*; D003863:Depression / Q000523:psychology; D004777:Environment; D006234:Handling, Psychological; D006624:Hippocampus / Q000378:metabolism; D046353:Immobility Response, Tonic; D007328:Insulin / Q000097:blood; D007333:Insulin Resistance / Q000502:physiology; D019964:Mood Disorders; D010296:Parietal Lobe / Q000378:metabolism; D051381:Rats; D000254:Sodium-Potassium-Exchanging ATPase / Q000378:metabolism*; D013315:Stress, Psychological / Q000150:complications* / Q000378:metabolism*; D013550:Swimming
chemical_list: D001786:Blood Glucose; D007328:Insulin; D000254:Sodium-Potassium-Exchanging ATPase; D003345:Corticosterone