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Abstract
Oxytocin (OT) is a nonapeptide mainly produced in the supraoptic and paraventricular nuclei. OT in the brain and blood has extensive functions in both mental and physical activities. These functions are mediated by OT receptors (OTRs) that are distributed in a broad spectrum of tissues with dramatic sexual dimorphism. In both sexes, OT generally facilitates social cognition and behaviors, facilitates parental behavior and sexual activity and inhibits feeding and pain perception. However, there are significant differences in OT levels and distribution of OTRs in men from women. Thus, many OT functions in men are different from women, particularly in the reproduction. In men, the reproductive functions are relatively simple. In women, the reproductive functions involve menstrual cycle, pregnancy, parturition, lactation, and menopause. These functions make OT regulation of women's health and disease a unique topic of physiological and pathological studies. In menstruation, pre-ovulatory increase in OT secretion in the hypothalamus and the ovary can promote the secretion of gonadotropin-releasing hormone and facilitate ovulation. During pregnancy, increased OT synthesis and preterm release endow OT system the ability to promote maternal behavior and lactation. In parturition, cervix expansion-elicited pulse OT secretion and uterine OT release accelerate the expelling of fetus and reduce postpartum hemorrhage. During lactation, intermittent pulsatile OT secretion is necessary for the milk-ejection reflex and maternal behavior. Disorders in OT secretion can account for maternal depression and hypogalactia. In menopause, the reduction of OT secretion accounts for many menopausal symptoms and diseases. These issues are reviewed in this work.
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Affiliation(s)
- Ning Liu
- Department of Obstetrics and Gynecology, Shengjing Hospital of China Medical University, Shenyang, China
| | - Haipeng Yang
- Neonatal Division of the Department of Pediatrics, The Fourth Affiliated Hospital of Harbin Medical University, Harbin, China
| | - Liqun Han
- Department of Radiology, The Fourth Affiliated Hospital of Harbin Medical University, Harbin, China
| | - Mingxing Ma
- Department of Colorectal Cancer Surgery, Shengjing Hospital of China Medical University, Shenyang, China
- Department of General Surgery, Shengjing Hospital of China Medical University, Shenyang, China
- *Correspondence: Mingxing Ma,
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Li D, Liu H, Wang H, Jia S, Wang X, Ling S, Chen G, Liu X, Wang YF. Astrocytic Hydrogen Sulfide Regulates Supraoptic Cellular Activity in the Adaptive Response of Lactating Rats to Chronic Social Stress. ASN Neuro 2021; 13:17590914211043087. [PMID: 34579557 PMCID: PMC8642056 DOI: 10.1177/17590914211043087] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023] Open
Abstract
Maternal social stress among breastfeeding women can be adapted in chronic process.
However, neuroendocrine mechanisms underlying such adaptation remain to be identified.
Here, we report the effects of 2 hr/day unfamiliar male rat invasion (UMI) stress on
maternal behaviors in lactating rats during postpartum day 8 (UMI8) to postpartum day 12
(UMI12). Rat dams at UMI8 presented signs of maternal anxiety, depression, and attacks
toward male intruder. These changes partially reversed at UMI12 except the sign of
anxiety. In the supraoptic nucleus (SON), UMI12 but not UMI8 significantly increased the
expression of c-Fos and phosphorylated extracellular signal-regulated protein kinase 1/2.
At UMI8 but not UMI12, length of glial fibrillary acidic protein (GFAP, astrocytic
cytoskeletal element) filaments around oxytocin (OT) neurons was significantly longer than
that of their controls; the amount of GFAP fragments at UMI12 was significantly less than
that at UMI8. Expression of cystathionine β-synthase (CBS, enzyme for H2S
synthesis) at UMI12 was significantly higher than that at UMI8. CBS expression did not
change significantly in the somatic zone of the SON but decreased significantly at the
ventral glia lamina at UMI8. In brain slices of the SON, aminooxyacetate (a CBS blocker)
significantly increased the expression of GFAP proteins that were molecularly associated
with CBS. Aminooxyacetate also reduced the firing rate of OT neurons whereas
Na2S, a donor of H2S, increased it. The adaptation during chronic
social stress is possibly attributable to the increased production of H2S by
astrocytes and the subsequent retraction of astrocytic processes around OT neurons.
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Affiliation(s)
- Dongyang Li
- Department of Physiology, 12455Hainan Medical University, Haikou, China.,Department of Physiology, School of Basic Medical Sciences, 34707Harbin Medical University, Harbin, China
| | - Haitao Liu
- Department of Physiology, School of Basic Medical Sciences, 34707Harbin Medical University, Harbin, China
| | - Hongyang Wang
- Department of Physiology, School of Basic Medical Sciences, 34707Harbin Medical University, Harbin, China
| | - Shuwei Jia
- Department of Physiology, School of Basic Medical Sciences, 34707Harbin Medical University, Harbin, China
| | - Xiaoran Wang
- Department of Physiology, School of Basic Medical Sciences, 34707Harbin Medical University, Harbin, China
| | - Shuo Ling
- Department of Physiology, School of Basic Medical Sciences, 34707Harbin Medical University, Harbin, China
| | - Guichuan Chen
- Department of Physiology, School of Basic Medical Sciences, 34707Harbin Medical University, Harbin, China
| | - Xiaoyu Liu
- Department of Physiology, School of Basic Medical Sciences, 34707Harbin Medical University, Harbin, China
| | - Yu-Feng Wang
- Department of Physiology, School of Basic Medical Sciences, 34707Harbin Medical University, Harbin, China
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Sheng W, Harden SW, Tan Y, Krause EG, Frazier CJ. Dendritic osmosensors modulate activity-induced calcium influx in oxytocinergic magnocellular neurons of the mouse PVN. eLife 2021; 10:e63486. [PMID: 34250900 PMCID: PMC8457833 DOI: 10.7554/elife.63486] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2020] [Accepted: 07/11/2021] [Indexed: 11/13/2022] Open
Abstract
Hypothalamic oxytocinergic magnocellular neurons have a fascinating ability to release peptide from both their axon terminals and from their dendrites. Existing data indicates that the relationship between somatic activity and dendritic release is not constant, but the mechanisms through which this relationship can be modulated are not completely understood. Here, we use a combination of electrical and optical recording techniques to quantify activity-induced calcium influx in proximal vs. distal dendrites of oxytocinergic magnocellular neurons located in the paraventricular nucleus of the hypothalamus (OT-MCNs). Results reveal that the dendrites of OT-MCNs are weak conductors of somatic voltage changes; however, activity-induced dendritic calcium influx can be robustly regulated by both osmosensitive and non-osmosensitive ion channels located along the dendritic membrane. Overall, this study reveals that dendritic conductivity is a dynamic and endogenously regulated feature of OT-MCNs that is likely to have substantial functional impact on central oxytocin release.
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Affiliation(s)
- Wanhui Sheng
- Department of Pharmacodynamics, College of Pharmacy, University of FloridaGainesvilleUnited States
| | - Scott W Harden
- Department of Pharmacodynamics, College of Pharmacy, University of FloridaGainesvilleUnited States
| | - Yalun Tan
- Department of Pharmacodynamics, College of Pharmacy, University of FloridaGainesvilleUnited States
- Department of Anesthesiology, School of Medicine, Stanford UniversityStanfordUnited States
| | - Eric G Krause
- Department of Pharmacodynamics, College of Pharmacy, University of FloridaGainesvilleUnited States
- Center for Integrative Cardiovascular and Metabolic Diseases, University of FloridaGainesvilleUnited States
- Evelyn F. and William L. McKnight Brain Institute, University of FloridaGainesvilleUnited States
| | - Charles J Frazier
- Department of Pharmacodynamics, College of Pharmacy, University of FloridaGainesvilleUnited States
- Center for Integrative Cardiovascular and Metabolic Diseases, University of FloridaGainesvilleUnited States
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Cao J, Meitzen J. Perinatal activation of ER α and ER β but not GPER-1 masculinizes female rat caudate-putamen medium spiny neuron electrophysiological properties. J Neurophysiol 2021; 125:2322-2338. [PMID: 33978486 DOI: 10.1152/jn.00063.2021] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
Exposure to steroid sex hormones such as 17β-estradiol (estradiol) during early life potentially permanently masculinize neuron electrophysiological phenotype. In rodents, one crucial component of this developmental process occurs in males, with estradiol aromatized in the brain from testes-sourced testosterone. However, it is unknown whether most neuron electrophysiological phenotypes are altered by this early masculinization process, including medium spiny neurons (MSNs) of the rat caudate-putamen. MSNs are the predominant and primary output neurons of the caudate-putamen and exhibit increased intrinsic excitability in females compared to males. Here, we hypothesize that since perinatal estradiol exposure occurs in males, then a comparable exposure in females to estradiol or its receptor agonists would be sufficient to induce masculinization. To test this hypothesis, we injected perinatal female rats with estradiol or its receptor agonists and then later assessed MSN electrophysiology. Female and male rats on postnatal day 0 and 1 were systemically injected with either vehicle, estradiol, the estrogen receptor (ER)α agonist PPT, the ERβ agonist DPN, or the G-protein-coupled receptor 1 (GPER-1) agonist G1. On postnatal days 19 ± 2, MSN electrophysiological properties were assessed using whole cell patch clamp recordings. Estradiol exposure abolished increased intrinsic excitability in female compared to male MSNs. Exposure to either an ERα or ERβ agonist masculinized female MSN evoked action potential firing rate properties, whereas exposure to an ERβ agonist masculinized female MSN inward rectification properties. Exposure to ER agonists minimally impacted male MSN electrophysiological properties. These findings indicate that perinatal estradiol exposure masculinizes MSN electrophysiological phenotype via activation of ERα and ERβ.NEW & NOTEWORTHY This study is the first to demonstrate that estradiol and estrogen receptor α and β stimulation during early development sexually differentiates the electrophysiological properties of caudate-putamen medium spiny neurons, the primary output neuron of the striatal regions. Overall, this evidence provides new insight into the neuroendocrine mechanism by which caudate-putamen neuron electrophysiology is sexually differentiated and demonstrates the powerful action of early hormone exposure upon individual neuron electrophysiology.
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Affiliation(s)
- Jinyan Cao
- Department of Biological Sciences, North Carolina State University, Raleigh, North Carolina
| | - John Meitzen
- Department of Biological Sciences, North Carolina State University, Raleigh, North Carolina.,Center for Human Health and the Environment, North Carolina State University, Raleigh, North Carolina.,Comparative Medicine Institute, North Carolina State University, Raleigh, North Carolina
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Brown CH, Ludwig M, Tasker JG, Stern JE. Somato-dendritic vasopressin and oxytocin secretion in endocrine and autonomic regulation. J Neuroendocrinol 2020; 32:e12856. [PMID: 32406599 PMCID: PMC9134751 DOI: 10.1111/jne.12856] [Citation(s) in RCA: 31] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/13/2020] [Revised: 03/29/2020] [Accepted: 04/11/2020] [Indexed: 12/29/2022]
Abstract
Somato-dendritic secretion was first demonstrated over 30 years ago. However, although its existence has become widely accepted, the function of somato-dendritic secretion is still not completely understood. Hypothalamic magnocellular neurosecretory cells were among the first neuronal phenotypes in which somato-dendritic secretion was demonstrated and are among the neurones for which the functions of somato-dendritic secretion are best characterised. These neurones secrete the neuropeptides, vasopressin and oxytocin, in an orthograde manner from their axons in the posterior pituitary gland into the blood circulation to regulate body fluid balance and reproductive physiology. Retrograde somato-dendritic secretion of vasopressin and oxytocin modulates the activity of the neurones from which they are secreted, as well as the activity of neighbouring populations of neurones, to provide intra- and inter-population signals that coordinate the endocrine and autonomic responses for the control of peripheral physiology. Somato-dendritic vasopressin and oxytocin have also been proposed to act as hormone-like signals in the brain. There is some evidence that somato-dendritic secretion from magnocellular neurosecretory cells modulates the activity of neurones beyond their local environment where there are no vasopressin- or oxytocin-containing axons but, to date, there is no conclusive evidence for, or against, hormone-like signalling throughout the brain, although it is difficult to imagine that the levels of vasopressin found throughout the brain could be underpinned by release from relatively sparse axon terminal fields. The generation of data to resolve this issue remains a priority for the field.
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Affiliation(s)
- Colin H. Brown
- Department of Physiology, Brain Health Research Centre, Centre for Neuroendocrinology, University of Otago, Dunedin, New Zealand
| | - Mike Ludwig
- Centre for Discovery Brain Sciences, University of Edinburgh, Edinburgh, UK
- Department of Immunology, Centre for Neuroendocrinology, University of Pretoria, Pretoria, South Africa
| | - Jeffrey G. Tasker
- Department of Cell and Molecular Biology, Brain Institute, Tulane University, New Orleans, LA, USA
| | - Javier E. Stern
- Neuroscience Institute, Georgia State University, Atlanta, GA, USA
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