Sex Specific Effects of Salt Loading in Oxytocin Neurons From The Supraoptic Nucleus

Confocal microscopy was used to assess activity-dependent neuroplasticity in neurotransmitter innervation of vasopressin immunoreactive magnocellular neurons in the supraoptic nucleus (SON). Vesicular glutamate transporter 2, glutamic acid decarboxylase, and dopamine β-hydroxylase (DBH) synaptic boutons were visualized in apposition to vasopressin neurons in the SON. A decrease in DBH synaptic boutons per cell was seen upon salt loading, indicating diminished noradrenergic/adrenergic innervation. Loss of DBH appositions to vasopressin neurons was associated with a general loss of DBH immunoreactivity in the SON. In contrast, the number of vesicular glutamate transporter 2 synaptic boutons per neuron increased with salt loading, consistent with increased glutamatergic drive of magnocellular SON neurons. Salt loading also caused an increase in the total number of glutamic acid decarboxylase synaptic boutons on vasopressinergic neurons, suggesting enhanced inhibitory innervation as well. These studies indicate that synaptic plasticity compensates for increased secretory demand and may indeed underlie increased secretion, perhaps via neurotransmitter-specific, activity-related changes in synaptic contacts on vasopressinergic magnocellular neurons in the SON.

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Rapid effect on suckling of an oxytocin antisense oligonucleotide administered into rat supraoptic nucleus

AJP Regulatory Integrative and Comparative Physiology ◽

10.1152/ajpregu.1994.267.3.r852 ◽

1994 ◽

Vol 267 (3) ◽

pp. R852-R858 ◽

Cited By ~ 6

Author(s):

I. Neumann ◽

D. W. Porter ◽

R. Landgraf ◽

Q. J. Pittman

Keyword(s):

Weight Gain ◽

Antisense Oligonucleotide ◽

Antisense Oligonucleotides ◽

Supraoptic Nucleus ◽

Milk Ejection ◽

Specific Effects ◽

Rapid Effect ◽

Left And Right ◽

Time To Onset ◽

Neuroendocrine Functions

Suckling in the lactating rat (days 6-10 of lactation) was used to characterize the effects of intracerebral oxytocin (Oxt) antisense oligonucleotide treatment on the hypothalamo-neurohypophysial system. Vehicle, mixed bases, Oxt antisense, or vasopressin antisense oligonucleotides (2.5 micrograms/0.5 microliter each) were infused directly into the left and right supraoptic nucleus (SON), 4 h before a litter of 10 pups was allowed to suckle for 30 min. In the Oxt antisense group, there was a significant reduction in the number of milk ejection reflexes (to 34.6 +/- 4.88%, P < 0.001), as well as in the weight gain of the litter (to 18.8 +/- 6.98%, P < 0.03) compared with vehicle (100%)-, mixed base-, or vasopressin antisense-treated animals, which did not differ from each other. The time to onset of suckling, however, was unchanged. Compared with presuckling values, plasma Oxt was significantly increased in all four groups 30 min after onset of suckling (vehicle, to 325 +/- 117%; mixed bases, to 258 +/- 48.2%; vasopressin antisense, to 330 +/- 55.7%), but this increase was less pronounced in Oxt antisense-treated rats (to 157 +/- 20.5%; P < 0.05 vs. vasopressin antisense). In contrast to these changes in neuroendocrine functions during suckling, Oxt as well as vasopressin content and Oxt immunoreactivity in posterior pituitaries and the SON, respectively, did not differ among groups. Our data indicate rapid and specific effects of an Oxt antisense oligonucleotide infused into the SON on neuroendocrine, suckling-related parameters that are not due to depleted stores of Oxt in the hypothalamo-neurohypophysial system.

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Differential Kinetics of Oxytocin and Vasopressin Heteronuclear RNA Expression in the Rat Supraoptic Nucleus in Response to Chronic Salt Loading In vivo

Journal of Neuroendocrinology ◽

10.1111/j.1365-2826.2007.01640.x ◽

2007 ◽

Vol 20 (2) ◽

pp. 227-232 ◽

Cited By ~ 19

Author(s):

C. Yue ◽

N. Mutsuga ◽

Y. Sugimura ◽

J. Verbalis ◽

H. Gainer

Keyword(s):

Supraoptic Nucleus ◽

Rna Expression ◽

Salt Loading ◽

Kinetics Of

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Time course of phosphorylated CREB and Fos-like immunoreactivity in the hypothalamic supraoptic nucleus after salt loading

Molecular Brain Research ◽

10.1016/0169-328x(94)00242-7 ◽

1995 ◽

Vol 29 (1) ◽

pp. 163-171 ◽

Cited By ~ 33

Author(s):

Priyattam J. Shiromani ◽

Meredith Magner ◽

Stuart Winston ◽

Michael E. Charness

Keyword(s):

Supraoptic Nucleus ◽

Time Course ◽

Salt Loading ◽

Phosphorylated Creb ◽

Hypothalamic Supraoptic Nucleus

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Correction: A RNA-Seq Analysis of the Rat Supraoptic Nucleus Transcriptome: Effects of Salt Loading on Gene Expression

PLoS ONE ◽

10.1371/journal.pone.0131892 ◽

2015 ◽

Vol 10 (6) ◽

pp. e0131892 ◽

Cited By ~ 1

Author(s):

Kory R. Johnson ◽

C. C. T. Hindmarch ◽

Yasmmyn D. Salinas ◽

YiJun Shi ◽

Michael Greenwood ◽

...

Keyword(s):

Gene Expression ◽

Supraoptic Nucleus ◽

Rna Seq ◽

Salt Loading

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Effects of Salt Loading on the Morphology of Astrocytes in the Ventral Glia Limitans of the Rat Supraoptic Nucleus

Journal of Neuroendocrinology ◽

10.1111/jne.12370 ◽

2016 ◽

Vol 28 (4) ◽

Cited By ~ 3

Author(s):

K. Y. Choe ◽

M. Prager-Khoutorsky ◽

W. T. Farmer ◽

K. K. Murai ◽

C. W. Bourque

Keyword(s):

Supraoptic Nucleus ◽

Salt Loading ◽

Glia Limitans

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A comparison of physiological and transcriptome responses to water deprivation and salt loading in the rat supraoptic nucleus

AJP Regulatory Integrative and Comparative Physiology ◽

10.1152/ajpregu.00444.2014 ◽

2015 ◽

Vol 308 (7) ◽

pp. R559-R568 ◽

Cited By ~ 24

Author(s):

Michael P. Greenwood ◽

Andre S. Mecawi ◽

See Ziau Hoe ◽

Mohd Rais Mustafa ◽

Kory R. Johnson ◽

...

Keyword(s):

Supraoptic Nucleus ◽

Water Deprivation ◽

Urine Osmolality ◽

Physiological Data ◽

Posterior Lobe ◽

Salt Loading ◽

False Discoveries ◽

The Impact ◽

The Brain ◽

Osmotic Stimuli

Salt loading (SL) and water deprivation (WD) are experimental challenges that are often used to study the osmotic circuitry of the brain. Central to this circuit is the supraoptic nucleus (SON) of the hypothalamus, which is responsible for the biosynthesis of the hormones, arginine vasopressin (AVP) and oxytocin (OXT), and their transport to terminals that reside in the posterior lobe of the pituitary. On osmotic challenge evoked by a change in blood volume or osmolality, the SON undergoes a function-related plasticity that creates an environment that allows for an appropriate hormone response. Here, we have described the impact of SL and WD compared with euhydrated (EU) controls in terms of drinking and eating behavior, body weight, and recorded physiological data including circulating hormone data and plasma and urine osmolality. We have also used microarrays to profile the transcriptome of the SON following SL and remined data from the SON that describes the transcriptome response to WD. From a list of 2,783 commonly regulated transcripts, we selected 20 genes for validation by qPCR. All of the 9 genes that have already been described as expressed or regulated in the SON by osmotic stimuli were confirmed in our models. Of the 11 novel genes, 5 were successfully validated while 6 were false discoveries.

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Molecular Characterization and Biological Function of Neuroendocrine Regulatory Peptide-3 in the Rat

Endocrinology ◽

10.1210/en.2011-1539 ◽

2012 ◽

Vol 153 (3) ◽

pp. 1377-1386 ◽

Cited By ~ 13

Author(s):

Hiroaki Fujihara ◽

Kazuki Sasaki ◽

Emi Mishiro-Sato ◽

Toyoaki Ohbuchi ◽

Govindan Dayanithi ◽

...

Keyword(s):

Paraventricular Nucleus ◽

Supraoptic Nucleus ◽

Biologically Active ◽

Regulatory Peptide ◽

Salt Loading ◽

Peptidomic Analysis ◽

Biologically Active Peptide ◽

Body Fluid Balance ◽

The Brain

Neuroendocrine regulatory peptide (NERP)-3, derived from the neurosecretory protein VGF (non-aconymic), is a new biologically active peptide identified through peptidomic analysis of the peptides secreted by an endocrine cell line. Using a specific antibody recognizing the C-terminal region of NERP-3, immunoreactive (ir)-NERP-3 was identified in acid extracts of rat brain and gut as a 30-residue NERP-3 with N-terminal pyroglutamylation. Assessed by radioimmunoassay, ir-NERP-3 was more abundant in the brain, including the posterior pituitary (PP), than in the gut. Immunohistochemistry demonstrated that ir-NERP-3 was significantly increased in the suprachiasmatic nucleus, the magnocellular division of the paraventricular nucleus, and the external layer of the median eminence, but not in the supraoptic nucleus, after dehydration. The immunoreactivity was, however, markedly decreased in all of these locations after chronic salt loading. Intracerebroventricular administration of NERP-3 in conscious rats induced Fos expression in a subset of arginine vasopressin (AVP)-containing neurons in the supraoptic nucleus and the magnocellular division of the paraventricular nucleus. On in vitro isolated rat PP preparations, NERP-3 caused a significant AVP release in a dose-related manner, suggesting that NERP-3 in the PP could be an autocrine activator of AVP release. Taken together, the present results suggest that NERP-3 in the hypothalamo-neurohypophyseal system may be involved in the regulation of body fluid balance.

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