In female rats, estradiol is responsible for a circadian secretory prolactin (PRL) pattern which requires an intact suprachiasmatic nucleus (SCN). SCN outputs involved in this secretory profile remain elusive. Because oxytocin has been proposed to stimulate PRL secretion, we investigated whether the projections of vasoactive intestinal polypeptide (VIP) from the SCN to neurons producing oxytocin in the paraventricular and periventricular nuclei (PVN and PeVN, respectively) are responsible for timing PRL surges induced by estradiol (E(2)). E(2)-treated ovariectomized rats received an injection of antisense or random-sequence oligodeoxynucleotide for VIP in the SCN and blood samples were taken for PRL measurements by radioimmunoassay. Additionally, the percentage of oxytocin-positive neurons immunoreactive to FOS-related antigens was determined in the PVN and PeVN, as an index of neuronal activity. In the PVN, oxytocinergic neuronal activity increased in the early evening regardless of E(2) treatment, whereas E(2) induced an increase of activity in the PeVN. VIP antisense attenuated this increase observed in both neuronal populations. Additionally, in the PeVN, VIP antisense advanced this increase by 2 h (from 19:00 h to 17:00 h). This same effect was observed in the PRL surge that occurred at 17:00 h in the VIP antisense injected animals. Thus, the SCN influences the precise timing of the E(2)-induced PRL surge via VIP projections to oxytocinergic neurons of the PVN and PeVN.
Download full-text PDF |
Source |
|---|---|
| http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2275054 | PMC |
| http://dx.doi.org/10.1016/j.brainres.2007.12.061 | DOI Listing |
Publication Analysis
Top Keywords
Similar Publications
Mechanisms for dysregulation of excitatory-inhibitory balance underlying allodynia in dorsal horn neural subcircuits.
PLoS Comput Biol
January 2025
Department of Mathematics and Statistics, Middlebury College, Middlebury, Vermont, United States of America.
Chronic pain is a wide-spread condition that is debilitating and expensive to manage, costing the United States alone around $600 billion in 2010. In a common symptom of chronic pain called allodynia, non-painful stimuli produce painful responses with highly variable presentations across individuals. While the specific mechanisms remain unclear, allodynia is hypothesized to be caused by the dysregulation of excitatory-inhibitory (E-I) balance in pain-processing neural circuitry in the dorsal horn of the spinal cord.
View Article and Find Full Text PDFmRNA Expression of Mineralocorticoid and Glucocorticoid Receptors in Human and Mouse Sensory Neurons of the Dorsal Root Ganglia.
Anesth Analg
September 2024
From the Department of Anesthesiology, Pain Research Center, University of Cincinnati College of Medicine, Cincinnati, Ohio.
Background: Corticosteroid receptors, including mineralocorticoid receptor (MR) and glucocorticoid receptor (GR), play important roles in inflammatory pain in the dorsal root ganglion (DRG). Although it is widely known that activating the GR reduces inflammatory pain, it has recently been shown that MR activation contributes to pain and neuronal excitability in rodent studies. Moreover, little is known about the translation of this work to humans, or the mechanisms through which corticosteroid receptors regulate inflammatory pain.
View Article and Find Full Text PDFCd99l2 regulates excitatory synapse development and restrains immediate-early gene activation.
Cell Rep
January 2025
Department of Biomedical Sciences, Seoul National University College of Medicine, Seoul 03080, South Korea; Neuroscience Research Institute, Medical Research Center, Seoul National University, Seoul 03080, South Korea; Transplantation Research Institute, Medical Research Center, Seoul National University, Seoul 03080, South Korea. Electronic address:
Cd99 molecule-like 2 (Cd99l2) is a type I transmembrane protein that plays a role in the transmigration of leukocytes across vascular endothelial cells. Despite its high expression in the brain, the role of Cd99l2 remains elusive. We find that Cd99l2 is expressed primarily in neurons and positively regulates neurite outgrowth and the development of excitatory synapses.
View Article and Find Full Text PDFGenistein-3'-sodium sulfonate suppresses NLRP3-mediated cell pyroptosis after cerebral ischemia.
Metab Brain Dis
January 2025
Key Laboratory of Prevention and treatment of cardiovascular and cerebrovascular diseases of Ministry of Education, Gannan Medical University, Ganzhou, 341000, China.
Cerebral ischemia-induced pyroptosis contributes to the dissemination of neuroinflammation, and Nod-like receptor protein-3 (NLRP3) inflammasome plays a key role in this process. Previous studies have indicated that Genistein-3'-sodiumsulfonate (GSS) can inhibit neuroinflammation caused by cerebral ischemia, exert cerebroprotective effects, but its specific mechanism has not been comprehensively understood. The aim of this study was to explore the effect of GSS on ischemic stroke-induced cell pyroptosis.
View Article and Find Full Text PDFTeMac™ ameliorates memory impairment and cholinergic dysfunction in rats induced by scopolamine.
Metab Brain Dis
January 2025
Department of Biochemistry, Faculty of Science, University of Yaoundé 1, P.O. Box 812, Yaounde, Cameroon.
Alzheimer's disease (AD) is associated with cognitive impairments which are linked to a deficit in cholinergic function. The objective of this study was to evaluate the ability of TeMac™ to prevent memory impairment in scopolamine-rats model of Alzheimer's disease and by in silico approaches to identify molecules in TeMac™ inhibiting acetylcholinesterase. The cholinergic cognitive dysfunction was induced by intraperitoneal injection of scopolamine (1 mg/kg daily) in male Wistar rats for seven consecutive days.
View Article and Find Full Text PDFWant AI Summaries of new PubMed Abstracts delivered to your In-box?
Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!