title: Social stress induces hypothalamo-pituitary-adrenal axis responses in lactating rats bred for high trait anxiety.
abstract: Hypothalamo-pituitary-adrenal axis responses to various stressors are typically attenuated during lactation, including in rats selectively bred for high or low anxiety. As high-anxiety dams are more aggressive towards intruders than low-anxiety dams during maternal defence, we investigated their hypothalamo-pituitary-adrenal axis responses to this social stress. Maternal defence induced elevated stress responses in high-anxiety dams only; nerve-growth-factor-induced gene B mRNA expression in the parvocellular paraventricular nucleus and adrenocorticotropin hormone secretory responses were substantially enhanced after maternal defence. In contrast, secretory responses to a non-social stress (elevated platform) were not different between high- and low-anxiety dams. Thus, responsiveness of the stress axis in lactation is dependent upon the innate level of anxiety of the dam and, as a consequence, her reactiveness to social threat.
authors.affiliation: Centre for Integrative Physiology, College of Medicine and Veterinary Medicine, The University of Edinburgh, Edinburgh, EH8 9XD, UK. alison.j.douglas@ed.ac.uk
authors.forename: A J
authors.initials: AJ
authors.lastname: Douglas
authors.forename: S L
authors.initials: SL
authors.lastname: Meddle
authors.forename: S
authors.initials: S
authors.lastname: Kroemer
authors.forename: W
authors.initials: W
authors.lastname: Muesch
authors.forename: O J
authors.initials: OJ
authors.lastname: Bosch
authors.forename: I D
authors.initials: ID
authors.lastname: Neumann
mesh_terms: D000324:Adrenocorticotropic Hormone / Q000378:metabolism; D000704:Analysis of Variance; D000818:Animals; D001007:Anxiety / Q000235:genetics* / Q000503:physiopathology*; D001522:Behavior, Animal; D004268:DNA-Binding Proteins / Q000235:genetics / Q000378:metabolism; D005106:Exploratory Behavior; D005260:Female; D007030:Hypothalamo-Hypophyseal System / Q000378:metabolism*; D019344:Lactic Acid / Q000378:metabolism*; D008297:Male; D008425:Maternal Behavior; D018782:Maze Learning / Q000502:physiology; D057105:Nuclear Receptor Subfamily 4, Group A, Member 1; D010913:Pituitary-Adrenal System / Q000378:metabolism*; D011247:Pregnancy; D051381:Rats; D018160:Receptors, Cytoplasmic and Nuclear / Q000235:genetics / Q000378:metabolism; D011987:Receptors, Steroid / Q000235:genetics / Q000378:metabolism; D013315:Stress, Psychological / Q000378:metabolism* / Q000473:pathology; D014157:Transcription Factors / Q000235:genetics / Q000378:metabolism
chemical_list: D004268:DNA-Binding Proteins; C539820:Nr4a1 protein, rat; D057105:Nuclear Receptor Subfamily 4, Group A, Member 1; D018160:Receptors, Cytoplasmic and Nuclear; D011987:Receptors, Steroid; D014157:Transcription Factors; D019344:Lactic Acid; D000324:Adrenocorticotropic Hormone