Clinical evidence of autonomic dysfunction due to atrial fibrillation: implications for rhythm control strategy.

Purpose: The role of the autonomic nervous system in the genesis of atrial fibrillation (AF) has been well studied; however, the converse remains poorly understood. Pulmonary veins (PV) contain receptors important in cardiac reflexes. Here, we evaluated reflex responses in patients with paroxysmal AF (PAF) to lower body negative pressure (LBNP).

Regulator of G protein signaling 5 is a determinant of gestational hypertension and preeclampsia.

Preeclampsia is a systemic vascular disorder of pregnancy and is associated with increased sensitivity to angiotensin II (AngII) and hypertension. The cause of preeclampsia remains unknown. We identified the role of regulator of G protein (heterotrimeric guanine nucleotide-binding protein) signaling 5 (RGS5) in blood pressure regulation during pregnancy and preeclampsia.

Does the Aged Care Funding Instrument provide increased funding in residential care? Comparisons with the Residential Classification Scale.

Aim: To determine whether the Aged Care Funding Instrument (ACFI) provides more funding than the Residential Classification Scale (RCS) for residents in the Hellenic Residential Care Facility.

Methods: All residents within the care facility were assessed over a six 6-month period using ACFI, RCS and Clifton Assessment Procedures for the Elderly (CAPE) scores. Differences in funding levels were calculated using ACFI and RCS instruments against a standardised CAPE score.

Regulator of G-protein signaling 5 controls blood pressure homeostasis and vessel wall remodeling.

Rationale: Regulator of G-protein signaling 5 (RGS5) modulates G-protein-coupled receptor signaling and is prominently expressed in arterial smooth muscle cells. Our group first reported that RGS5 is important in vascular remodeling during tumor angiogenesis. We hypothesized that RGS5 may play an important role in vessel wall remodeling and blood pressure regulation.

Changes in oxygen tension affect cardiac mitochondrial respiration rate via changes in the rate of mitochondrial hydrogen peroxide production.

The capacity of mitochondria to respond to changes in oxygen delivery has the potential to affect the ability of the heart to tolerate decreased oxygen delivery. Respiration by mitochondria is typically regarded as independent of oxygen tension (pO(2)) until critically low oxygen concentrations limit the activity of cytochrome oxidase. Paradoxically, there is evidence that cellular and mitochondrial oxygen consumption (respiration) can decline at oxygen tensions well above this critical pO(2).

Immunohistochemical assessment of cyclic guanosine monophosphate (cGMP) and soluble guanylate cyclase (sGC) within the rostral ventrolateral medulla.

Functional evidence suggests that nitric oxide (NO) signalling in the rostral ventrolateral medulla (RVLM) is cGMP-dependent and that this pathway is impaired in hypertension. We examined cGMP expression as a marker of active NO signalling in the C1 region of the RVLM, comparing adult (>18 weeks) Wistar-Kyoto (WKY, n = 4) and spontaneously hypertensive rats (SHR, n = 4). Double label immunohistochemistry for cGMP-immunoreactivity (IR) and C1 neurons [as identified by phenylethanolamine N-methyltransferase (PNMT-IR) or tyrosine hydroxylase TH-IR)], or neuronal NO synthase (nNOS) neurones, failed to reveal cGMP-IR neurons in the RVLM of either strain, despite consistent detection of cGMP-IR in the nucleus ambiguus (NA).

Temporal relationship between renal cyst development, hypertension and cardiac hypertrophy in a new rat model of autosomal recessive polycystic kidney disease.

Background/methods: We have examined the hypothesis that cyst formation is key in the pathogenesis of cardiovascular disease in a Lewis polycystic kidney (LPK) model of autosomal-recessive polycystic kidney disease (ARPKD), by determining the relationship between cyst development and indices of renal function and cardiovascular disease.

Results: In the LPK (n = 35), cysts appear at week 3 (1.1 +/- 0.

Distinct subpopulations of cyclic guanosine monophosphate (cGMP) and neuronal nitric oxide synthase (nNOS) containing sympathetic preganglionic neurons in spontaneously hypertensive and Wistar-Kyoto rats.

The sympathetic preganglionic neurons (SPN) of the intermediolateral cell column (IML) play a critical role in the maintenance of vascular tone. We undertook a comparative neuroanatomical analysis of neuronal nitric oxide synthase (nNOS) expression in the SPN of the mature normotensive Wistar Kyoto (WKY) and spontaneously hypertensive rat (SHR). The anatomical relationship between nNOS and the NO signaling molecule cyclic guanosine monophosphate (cGMP) was also determined.

Unique levels of expression of N-methyl-D-aspartate receptor subunits and neuronal nitric oxide synthase in the rostral ventrolateral medulla of the spontaneously hypertensive rat.

The rostral ventrolateral medulla (RVLM) is the major brainstem region contributing to sympathetic control of blood pressure. We have compared the expression of N-methyl-d-aspartate (NMDA) receptor subunits (NR1, NR2A-D), NR1 splice variants (NR1-1a/1b, -2a/2b, -3a/3b, -4a/4b), and the neuronal and inducible isoforms of NO synthase (nNOS and iNOS) in the RVLM of Wistar Kyoto (WKY) and spontaneously hypertensive rats (SHR), based on the hypothesis that altered NMDA receptor make-up or altered expression of endogenous NO may be associated with the increase in sympathetic output described from this site in hypertension. Total RNA was extracted and reverse transcribed from the RVLM of mature male WKY and SHR (16-23 weeks).

Vasomotor responses to decreased venous return: effects of cardiac deafferentation in humans.

We compared haemodynamic and peripheral vasomotor responses to lower body negative pressure (LBNP) in cardiac transplant recipients who had undergone bicaval anastomoses, involving right atrial deafferentation (-RA), and the conventional procedure in which some atrial baroreceptor afferents remain intact (+RA). We measured mean forearm blood flow (FBF) responses using Doppler/ultrasound during three randomised trials involving 0 (baseline), -20 and -40 mmHg LBNP in 15 transplant recipients (9 -RA, 6 +RA) and in eight healthy matched controls. A significant effect of LBNP on FBF existed between control and transplant groups (P < 0.