The effects of emotional stressors on the release of arginine vasopressin (AVP) and oxytocin (OXT) within the rat hypothalamus and the origin and physiological significance of AVP released within the hypothalamic paraventricular nucleus (PVN) were investigated. First, adult male Wistar rats with a microdialysis probe aimed at the PVN or the supraoptic nucleus were exposed to either a dominant male rat (social defeat) or a novel cage. Release of AVP within the PVN was significantly increased in response to social defeat but not to novelty. In contrast to an activation of the hypothalamic-pituitary-adrenal (HPA) system, neither stressor stimulated the hypothalamic-neurohypophysial system (unchanged plasma AVP and OXT and unchanged release within the supraoptic nucleus [AVP] and the PVN [OXT]). Next, we demonstrated by simultaneous microdialysis of the suprachiasmatic nucleus and the PVN that AVP measured in PVN dialysates during social defeat was probably of intranuclear origin. Finally, a mixture of a V1 AVP and the alpha-helical corticotropin-releasing hormone (CRH) receptor antagonists administered via inverse microdialysis into the PVN caused a significant increase in the plasma adrenocorticotropic hormone (ACTH) concentration compared with vehicle-treated controls both under basal conditions and during social defeat, indicating inhibitory effects of intra-PVN-released AVP and/or CRH on HPA system activity. The antagonists failed to affect anxiety-related behavior of the animals as assessed with the elevated plus-maze. Taken together, our results show for the first time that AVP is released within the PVN in response to an emotional stressor. We hypothesize that this intranuclear release provides a negative tonus on ACTH secretion.
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http://dx.doi.org/10.1523/JNEUROSCI.16-23-07725.1996 | DOI Listing |
Dev Psychobiol
January 2025
Department of Psychology, The University of Tennessee Knoxville, Knoxville, Tennessee, USA.
Long-term effects of social play on neural and behavioral development remain unclear. We investigated whether just 1 h of juvenile social play could rescue the effects of play deprivation on stress-related behavior and markers of neural plasticity. Syrian hamsters were reared from postnatal days 21-43 in three conditions: peer isolation, peer isolation with daily social play sessions (dyadic play), or group-housed with littermates.
View Article and Find Full Text PDFJ Hist Behav Sci
January 2025
Department of Psychology, Oklahoma State University, Stillwater, Oklahoma, USA.
Although naturalists have devoted attention to cetaceans since Antiquity, it was only in the 19th century that cetology underwent a true explosion. Three key cetological works of this period are The Natural History of the Sperm Whale (1839) by Thomas Beale, The Whaleman's Adventures in the Southern Ocean (1850) by Henry Cheever and The Seals and Whales of the British Seas (1881) by Thomas Southwell. Importantly, these three works did not only represent fundamental compendia of scientific knowledge of cetaceans, but also had a crucial role in awakening a cetacean protection consciousness.
View Article and Find Full Text PDFPLoS One
January 2025
Division of Oral Physiology, Faculty of Dentistry, Niigata University Graduate School of Medical and Dental Sciences, Niigata, Japan.
This study examined the effects of treadmill running (TR) regimens on craniofacial pain- and anxiety-like behaviors, as well as their effects on neural changes in specific brain regions of male mice subjected to repeated social defeat stress (SDS) for 10 days. Behavioral and immunohistochemical experiments were conducted to evaluate the impact of TR regimens on SDS-related those behaviors, as well as epigenetic and neural activity markers in the anterior cingulate cortex (ACC), insular cortex (IC), rostral ventromedial medulla (RVM), and cervical spinal dorsal horn (C2). Behavioral responses were quantified using multiple tests, while immunohistochemistry measured histone H3 acetylation, histone deacetylases (HDAC1, HDAC2), and neural activity markers (FosB and phosphorylated cAMP response element-binding protein (pCREB).
View Article and Find Full Text PDFBiomolecules
January 2025
Research and Education Resource Center, Peoples Friendship University of Russia (RUDN University), 117198 Moscow, Russia.
Post-translational modifications of proteins via palmitoylation, a thioester linkage of a 16-carbon fatty acid to a cysteine residue, reversibly increases their affinity for cholesterol-rich lipid rafts in membranes, changing their function. Little is known about how altered palmitoylation affects function at the systemic level and contributes to CNS pathology. However, recent studies suggested a role for the downregulation of palmitoyl acetyltransferase (DHHC) 21 gene expression in the development of Major Depressive Disorder (MDD)-like syndrome.
View Article and Find Full Text PDFMetabolites
January 2025
Jiangsu Provincial Key Laboratory of Drug Metabolism and Pharmacokinetics, State Key Laboratory of Natural Medicines, China Pharmaceutical University, Nanjing 210009, China.
Background: There is a high rate of depressive symptoms such as irritability, anhedonia, fatigue, and hypersomnia in patients with type 2 diabetes mellitus (T2DM). However, the causes and underlying mechanisms of the comorbidity of depression and diabetes remain unknown.
Methods: For the first time, we identified Decidual protein induced by progesterone 1 (Depp1), also known as DEPP autophagy regulator 1, as a hub gene in both depression and T2DM models.
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