title: Interconnectivity of sympathetic and sleep networks is mediated through reduction of gamma aminobutyric acidergic inhibition in the paraventricular nucleus.
abstract: Chronic short sleep duration has been linked to sympathoexcitation and increased risk of cardiovascular disease. The central nervous system plays an important role in the regulation of sympathetic activity. Thus, the present study evaluates the pre-autonomic neurones in the paraventricular nucleus of the hypothalamus and rostral ventrolateral medulla after sleep restriction using various protein expression measurements and electrophysiological approaches. Wistar male rats were assigned randomly to two experimental groups: control or sleep restriction for 14 days. Sleep restriction was defined as 20 h of paradoxical sleep deprivation followed by a 4 h sleep permission period using the modified multiple platform method. Micropunches of the paraventricular nucleus of the hypothalamus and rostral ventrolateral medulla were dissected to evaluate the protein expression of angiotensin II receptor, type 1 (AT1), AT2, gamma aminobutyric acidA ) (N-methyl-d-aspartate receptor1) and neuronal nitric oxide synthase neuronal nitric oxide synthase isoform through immunoblotting. Sleep restriction induced a down-regulation of the gamma aminobutyric acidA receptor in the paraventricular nucleus of the hypothalamus. Microinjection of bicuculline, a gamma aminobutyric acid receptor blocker, into the paraventricular nucleus of the hypothalamus increased renal sympathetic activity renal sympathetic nerve activity, mean arterial pressure and heart rate in anaesthetized control rats. However, the amplitude and frequency of renal sympathetic nerve activity was higher in the sleep restriction group. These findings suggest that gamma aminobutyric acidergic inhibition within the paraventricular nucleus of the hypothalamus is involved in sympathoexcitation induced by sleep restriction.
authors.affiliation: Department of Psychobiology, Universidade Federal de São Paulo, São Paulo, SP, Brazil.
authors.forename: Juliana C
authors.initials: JC
authors.lastname: Perry
authors.forename: Cássia T
authors.initials: CT
authors.lastname: Bergamaschi
authors.forename: Ruy R
authors.initials: RR
authors.lastname: Campos
authors.forename: Adilson M
authors.initials: AM
authors.lastname: Silva
authors.forename: Sergio
authors.initials: S
authors.lastname: Tufik
mesh_terms: D000818:Animals; D001640:Bicuculline / Q000008:administration & dosage / Q000494:pharmacology; D001794:Blood Pressure / Q000187:drug effects; D015536:Down-Regulation; D006339:Heart Rate / Q000187:drug effects; D007668:Kidney / Q000294:innervation / Q000378:metabolism; D008297:Male; D008526:Medulla Oblongata / Q000378:metabolism / Q000503:physiopathology; D008845:Microinjections; D052248:Nitric Oxide Synthase Type I / Q000378:metabolism; D010286:Paraventricular Hypothalamic Nucleus / Q000378:metabolism* / Q000502:physiology / Q000503:physiopathology; D011897:Random Allocation; D051381:Rats; D017208:Rats, Wistar; D044140:Receptor, Angiotensin, Type 1 / Q000378:metabolism; D044139:Receptor, Angiotensin, Type 2 / Q000378:metabolism; D016194:Receptors, N-Methyl-D-Aspartate / Q000378:metabolism; D012892:Sleep Deprivation / Q000378:metabolism* / Q000503:physiopathology*; D013564:Sympathetic Nervous System / Q000378:metabolism* / Q000502:physiology / Q000503:physiopathology; D005680:gamma-Aminobutyric Acid / Q000187:drug effects / Q000378:metabolism*
chemical_list: D001640:Bicuculline; D052248:Nitric Oxide Synthase Type I; D044140:Receptor, Angiotensin, Type 1; D044139:Receptor, Angiotensin, Type 2; D016194:Receptors, N-Methyl-D-Aspartate; D005680:gamma-Aminobutyric Acid; C544067:Agtr1a protein, rat; C496320:NOS1 protein, human
keywords: cardiovascular system; gamma aminobutyric acid; paraventricular nucleus; sleep; sleep restriction; sympathetic activity