title: The effects of early-life stress on dopamine system function in adolescent female rats.
abstract: During adolescence, many neural systems, including the dopamine system, undergo essential remodeling and maturation. It is well known that early-life stress (ELS) increases the risk for many psychopathologies during adolescence and adulthood. It is hypothesized that ELS interferes with the maturation of the dopamine system. There is a sex bias in the prevalence of stress-related mental disorders. Information regarding the effects of ELS on brain functioning in females is very limited. In the current study, maternal separation (MS) procedures were carried out to study the effects of ELS on dopamine system functioning in adolescent female rats. Our study showed that MS increased the density of tyrosine hydroxylase immunoreactive fibers in the prelimbic cortex (PLC) and nucleus accumbens (Acb). These changes were accompanied by a decrease in the level of D5 receptor mRNA and an increase in D2 receptor mRNA expression in the PLC of MS females. Conversely, D1 and D5 receptor mRNA levels were augmented in the caudate putamen (CPu), while the expression of the D3 dopamine receptor transcript was reduced in MS females. Additionally, in the Acb, MS elicited a decrease in D2 receptor mRNA expression. At the behavioral level, MS increased apomorphine-induced locomotion; however, it did not change locomotor responses to selective D1/D5 receptor agonist and attenuated D2/D3 receptor agonist-triggered locomotion. Moreover, MS decreased D1/D5 receptor agonist-induced grooming behavior. These results indicate that ELS disrupts dopamine receptor function in the PLC and basal ganglia during adolescence in females and may predispose them to psychopathologies during adolescence and adulthood.
authors.affiliation: Institute of Pharmacology, Polish Academy of Sciences, Laboratory of Pharmacology and Brain Biostructure, 31-343 Kraków, Smętna Street 12, Poland.
authors.forename: Iwona
authors.initials: I
authors.lastname: Majcher-Maślanka
authors.affiliation: Institute of Pharmacology, Polish Academy of Sciences, Laboratory of Pharmacology and Brain Biostructure, 31-343 Kraków, Smętna Street 12, Poland.
authors.forename: Anna
authors.initials: A
authors.lastname: Solarz
authors.affiliation: Institute of Pharmacology, Polish Academy of Sciences, Laboratory of Pharmacology and Brain Biostructure, 31-343 Kraków, Smętna Street 12, Poland.
authors.forename: Krzysztof
authors.initials: K
authors.lastname: Wędzony
authors.affiliation: Institute of Pharmacology, Polish Academy of Sciences, Laboratory of Pharmacology and Brain Biostructure, 31-343 Kraków, Smętna Street 12, Poland. Electronic address: chocyk@if-pan.krakow.pl.
authors.forename: Agnieszka
authors.initials: A
authors.lastname: Chocyk
mesh_terms: D000818:Animals; D000831:Animals, Newborn; D001921:Brain / Q000187:drug effects / Q000254:growth & development* / Q000378:metabolism*; D004195:Disease Models, Animal; D004298:Dopamine / Q000378:metabolism*; D015259:Dopamine Agents / Q000494:pharmacology; D005260:Female; D018507:Gene Expression Regulation, Developmental / Q000187:drug effects / Q000502:physiology*; D006120:Grooming / Q000187:drug effects / Q000502:physiology; D008124:Locomotion / Q000187:drug effects / Q000502:physiology; D008426:Maternal Deprivation; D012333:RNA, Messenger / Q000378:metabolism; D051381:Rats; D017208:Rats, Wistar; D011954:Receptors, Dopamine / Q000235:genetics / Q000378:metabolism; D013315:Stress, Psychological / Q000209:etiology / Q000473:pathology* / Q000503:physiopathology; D014446:Tyrosine 3-Monooxygenase / Q000235:genetics / Q000378:metabolism
chemical_list: D015259:Dopamine Agents; D012333:RNA, Messenger; D011954:Receptors, Dopamine; D014446:Tyrosine 3-Monooxygenase; D004298:Dopamine
keywords: Adolescence; Basal ganglia; Dopamine receptors; Females; Maternal separation; Tyrosine hydroxylase