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(Reference retrieved automatically from Web of Science through information on FAPESP grant and its corresponding number as mentioned in the publication by the authors.)

Subdiaphragmatic vagus nerve activity and hepatic venous glucose are differentially regulated by the central actions of insulin in Wistar and SHR

Full text
Author(s):
Ribeiro, Izabela Martina R. ; Ferreira-Neto, Hildebrando C. ; Antunes, Vagner R.
Total Authors: 3
Document type: Journal article
Source: PHYSIOLOGICAL REPORTS; v. 3, n. 5 MAY 2015.
Web of Science Citations: 4
Abstract

Glucose is the most important energy substrate for the maintenance of tissues function. The liver plays an essential role in the control of glucose production, since it is able to synthesize, store, and release glucose into the circulation under different situations. Hormones like insulin and catecholamines influence hepatic glucose production (HGP), but little is known about the role of the central actions of physiological doses of insulin in modulating HGP via the autonomic nervous system in nonanesthetized rats especially in SHR where we see a high degree of insulin resistance and metabolic dysfunction. Wistar and SHR received ICV injection of insulin (100 nU/mu L) and hepatic venous glucose concentration (HVGC) was monitored for 30 min, as an indirect measure of HGP. At 10 min after insulin injection, HVGC decreased by 27% in Wistar rats, with a negligible change (3%) in SHR. Pretreatment with atropine totally blocked the reduction in HVGC, while pretreatment with propranolol and phentolamine induced a decrease of 8% in HVGC after ICV insulin injection in Wistar. Intracarotid infusion of insulin caused a significant increase in subdiaphragmatic vagus nerve (SVN) activity in Wistar (12 +/- 2%), with negligible effects on the lumbar splanchnic sympathetic nerve (LSSN) activity (-6 +/- 3%). No change was observed in SVN (-2 +/- 2%) and LSSN activities (2 +/- 3%) in SHR after ICA insulin infusion. Taken together, these results show, in nonanesthetized animals, the importance of the parasympathetic nervous system in controlling HVGC, and subdiaphragmatic nerve activity following central administration of insulin; a mechanism that is impaired in the SHR. (AU)

FAPESP's process: 07/04085-0 - Functional analysis of genes contributing to neurogenic hypertension
Grantee:Vagner Roberto Antunes
Support type: Regular Research Grants
FAPESP's process: 10/05037-1 - Role of purinergic receptors of paraventricular nucleus of the hypothalamus in the neurogenic hypertension
Grantee:Hildebrando Candido Ferreira Neto
Support type: Scholarships in Brazil - Doctorate
FAPESP's process: 13/06206-0 - Gene expression changes of neuropeptides and proinflammatory factors of the hypothalamus and brainstem nucleus involved with cardiovascular regulation in diet-induced obesity animals
Grantee:Vagner Roberto Antunes
Support type: Regular Research Grants
FAPESP's process: 09/13047-0 - Role of the autonomic nervous system in the hepatic production of glucose via central action of insulin in hypertensive animals
Grantee:Izabela Martina Ramos Ribeiro de Toledo
Support type: Scholarships in Brazil - Master