Linked Life Data

18047553

Source:http://linkedlifedata.com/resource/pubmed/id/18047553

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
2
pubmed:dateCreated
2008-1-30
pubmed:abstractText
Salusin-alpha and -beta were recently discovered as bioactive endogenous peptides. In the present study, we investigated the effects of chronic osmotic stimuli on salusin-beta-like immunoreactivity (LI) in the rat hypothalamo-neurohypophyseal system. We examined the effects of salusin-beta on synaptic inputs to the rat magnocellular neurosecretory cells (MNCs) of the supraoptic nucleus (SON) and neurohypophyseal hormone release from both freshly dissociated SONs and neurohypophyses in rats. Immunohistochemical studies revealed that salusin-beta-LI neurones and fibres were markedly increased in the SON and the magnocellular division of the paraventricular nucleus after chronic osmotic stimuli resulting from salt loading for 5 days and dehydration for 3 days. Salusin-beta-LI fibres and varicosities in the internal zone of the median eminence and the neurohypophysis were also increased after osmotic stimuli. Whole-cell patch-clamp recordings from rat SON slice preparations showed that salusin-beta did not cause significant changes in the excitatory and inhibitory postsynaptic currents of the MNCs. In vitro hormone release studies showed that salusin-beta evoked both arginine vasopressin (AVP) and oxytocin release from the neurohypophysis, but not the SON. In our hands, in the neurohypophysis, a significant release of AVP and oxytocin was observed only at concentrations from 100 nm and above of salusin-beta. Low concentrations below 100 nm were ineffective both on AVP and oxytocin release. We also measured intracellular calcium ([Ca(2+)](i)) increase induced by salusin-beta on freshly-isolated single nerve terminals from the neurohypophysis devoid of pars intermedia. Furthermore, this salusin-beta-induced [Ca(2+)](i) increase was blocked in the presence of high voltage activated Ca(2+)channel blockers. Our results suggest that salusin-beta may be involved in the regulation of body fluid balance by stimulating neurohypophyseal hormone release from nerve endings by an autocrine/paracrine mechanism.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Feb
pubmed:issn
1365-2826
pubmed:author
pubmed:issnType
Electronic
pubmed:volume
20
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
207-19
pubmed:meshHeading
pubmed-meshheading:18047553-Animals, pubmed-meshheading:18047553-Arginine Vasopressin, pubmed-meshheading:18047553-Calcium, pubmed-meshheading:18047553-Excitatory Postsynaptic Potentials, pubmed-meshheading:18047553-Hypothalamo-Hypophyseal System, pubmed-meshheading:18047553-Immunohistochemistry, pubmed-meshheading:18047553-Inhibitory Postsynaptic Potentials, pubmed-meshheading:18047553-Intercellular Signaling Peptides and Proteins, pubmed-meshheading:18047553-Intracellular Membranes, pubmed-meshheading:18047553-Male, pubmed-meshheading:18047553-Osmolar Concentration, pubmed-meshheading:18047553-Osmosis, pubmed-meshheading:18047553-Oxytocin, pubmed-meshheading:18047553-Patch-Clamp Techniques, pubmed-meshheading:18047553-Pituitary Gland, Posterior, pubmed-meshheading:18047553-Pituitary Hormones, Posterior, pubmed-meshheading:18047553-Presynaptic Terminals, pubmed-meshheading:18047553-Rats, pubmed-meshheading:18047553-Rats, Wistar, pubmed-meshheading:18047553-Sodium Chloride, pubmed-meshheading:18047553-Supraoptic Nucleus
pubmed:year
2008
pubmed:articleTitle
Chronic osmotic stimuli increase salusin-beta-like immunoreactivity in the rat hypothalamo-neurohypophyseal system: possible involvement of salusin-beta on [Ca2+]i increase and neurohypophyseal hormone release from the axon terminals.
pubmed:affiliation
Department of Physiology, School of Medicine, University of Occupational and Environmental Health, Kitakyushu, Japan.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't