Altered Balance of gamma-Aminobutyric Acidergic and Glutamatergic Afferent Inputs in Rostral Ventrolateral Medulla-Projecting Neurons in the Paraventricular Nucleus of the Hypothalamus of Renovascular Hypertensive Rats

Altered Balance of gamma-Aminobutyric Acidergic and Glutamatergic Afferent Inputs in Rostral Ventrolateral Medulla-Projecting Neurons in the Paraventricular Nucleus of the Hypothalamus of Renovascular Hypertensive Rats

Author Biancardi, Vinicia Campana Google Scholar
Campos, Ruy Ribeiro Autor UNIFESP Google Scholar
Stern, Javier Eduardo Google Scholar
Institution Med Coll Georgia
Universidade Federal de São Paulo (UNIFESP)
Abstract An imbalance of excitatory and inhibitory functions has been shown to contribute to numerous pathological disorders. Accumulating evidence supports the idea that a change in hypothalamic gamma-aminobutyric acid (GABA)-ergic inhibitory and glutamatergic excitatory synaptic functions contributes to exacerbated neurohumoral drive in prevalent cardiovascular disorders, including hypertension. However, the precise underlying mechanisms and neuronal substrates are still not fully elucidated in the present study, we combined quantitative immunohistochemistry with neuronal tract tracing to determine whether plastic remodeling of afferent GABAergic and glutamatergic inputs into identified RVLM-projecting neurons of the hypothalamic paraventricular nucleus (PVN-RVLM) contributes to an imbalanced excitatory/inhibitory function in renovascular hypertensive rats (RVH). Our results indicate that both GABAergic and glutamatergic innervation densities increased in oxytocin-positive, PVN-RVLM (OT-PVN-RVLM) neurons in RVH rats. Despite this concomitant increase, time-dependent and compartment-specific differences in the reorganization of these inputs resulted in an altered balance of excitatory/inhibitory inputs in somatic and dendritic compartments. A net predominance of excitatory over inhibitory inputs was found in OT-PVN-RVLM proximal dendrites. Our results indicate that, along with previously described changes in neurotransmitter release probability and postsynaptic receptor function, remodeling of GABAergic and glutamatergic afferent inputs contributes as an underlying mechanism to the altered excitatory/inhibitory balance in the PVN of hypertensive rats. J. Comp. Neurol. 518:567-585, 2010. (C) 2009 Wiley-Liss, Inc
Keywords synaptic
sympathetic
plasticity
brainstem
immunohistochemistry
hypertension
Language English
Sponsor National Institutes of Health
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)
Grant number National Institutes of Health: R01HL68725
CAPES: BEX0325/03-1
Date 2010-03-01
Published in Journal of Comparative Neurology. Hoboken: Wiley-liss, v. 518, n. 5, p. 567-585, 2010.
ISSN 0021-9967 (Sherpa/Romeo, impact factor)
Publisher Wiley-Blackwell
Extent 567-585
Origin http://dx.doi.org/10.1002/cne.22256
Access rights Closed access
Type Review
Web of Science ID WOS:000273620800001
URI http://repositorio.unifesp.br/handle/11600/32311

Show full item record




File

File Size Format View

There are no files associated with this item.

This item appears in the following Collection(s)

Search


Browse

Statistics

My Account