Central blockade of nitric oxide synthesis reduces moxonidine-induced hypotension

1 Nitric oxide (NO) and alpha(2)-adrenoceptor and imidazoline agonists such as moxonidine may act centrally to inhibit sympathetic activity and decrease arterial pressure.2 In the present study, we investigated the effects of pretreatment with L-NAME ( NO synthesis inhibitor), injected into the 4th ventricle (4th V) or intravenously (i.v.), on the hypotension, bradycardia and vasodilatation induced by moxonidine injected into the 4th V in normotensive rats.3 Male Wistar rats with a stainless steel cannula implanted into the 4th V and anaesthetized with urethane were used. Blood flows were recorded by use of miniature pulsed Doppler flow probes implanted around the renal, superior mesenteric and low abdominal aorta.4 Moxonidine (20 nmol), injected into the 4th V, reduced the mean arterial pressure (-42+/-3 mmHg), heart rate (-22+/-7 bpm) and renal (-62+/-15%), mesenteric (-41+/-8%) and hindquarter (-50+/-8%) vascular resistances.5 Pretreatment with L-NAME (10 nmol into the 4th V) almost abolished central moxonidine-induced hypotension (-10+/-3 mmHg) and renal (-10+/-4%), mesenteric (-11+/-4%) and hindquarter (-13+/-6%) vascular resistance reduction, but did not affect the bradycardia (-18+/-8 bpm).6 the results indicate that central NO mechanisms are involved in the vasodilatation and hypotension, but not in the bradycardia, induced by central moxonidine in normotensive rats. British Journal of Pharmacology (2004).

Effects of subtypes of adrenergic and angiotensinergic antagonists on the water and sodium intake induced by adrenaline injected into the paraventricular nucleus

The present experiments were conducted to investigate die role of the alpha(1A)-, alpha(1B)-, beta(1)-, beta(2)-adrenoceptors, and the effects of losartan and CGP42112A (selective ligands of the AT(1) and AT(2) angiotensin receptors, respectively) on the water and sodium intake elicited by paraventricular nucleus (PVN) injection of adrenaline. Male Holtzman rats with a stainless steel cannula implanted into the PVN were used. The ingestion of water and sodium was determined in separate groups submitted to water deprivation or sodium depletion with the diuretic furosemide (20 mg/rat). 5-Methylurapidil (an alpha(1A)-adrenergic antagonist) and ICI-118,551 (a beta(2)-adrenergic antagonist) injected into the PVN produced a dose-dependent increase, whereas cyclazosin (an alpha(1B)-adrenergic antagonist) and atenolol (a beta(1)-adrenergic antagonist) do not affect the inhibitory effect of water intake induced by adrenaline. on the other hand, the PVN administration of adrenaline increased the sodium intake in a dose-dependent manner. Previous injection of the alpha(1A) and beta(1) antagonists decreased, whereas injection of the alpha(1B) and beta(2) antagonists increased the salt intake induced by adrenaline. In rats with several doses of adrenaline into PVN, the previous administration of losartan increased in a dose-dependent manner the inhibitory effect of adrenaline and decreased the salt intake induced by adrenaline, while PVN CGP42112A was without effect. These results indicate that both appetites are mediated primarily by brain AT(1) receptors. However, the doses of losartan were more effective when combined with the doses of CGP42112A than given alone p < 0.05, suggesting that the water and salt intake effects of PVN adrenaline may involve activation of multiple angiotensin II (ANG II) receptors subtypes. (C) 2003 Elsevier B.V. All rights reserved.

Adrenergic mechanisms of the Kölliker-Fuse/A7 area on the control of water and sodium intake

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Moxonidine into the lateral parabrachial nucleus reduces renal and hormonal responses to cell dehydration

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Involvement of central alpha(1)-adrenoceptors on renal responses to central moxonidine and alpha-methylnoradrenaline

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Effect of exogenous galectin-1 on leukocyte migration: modulation of cytokine levels and adhesion molecules

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Zeros of Jacobi functions of second kind

The number of zeros in (- 1, 1) of the Jacobi function of second kind Q(n)((alpha, beta)) (x), alpha, beta > - 1, i.e. The second solution of the differential equation(1 - x(2))y (x) + (beta - alpha - (alpha + beta + 2)x)y' (x) + n(n + alpha + beta + 1)y(x) = 0,is determined for every n is an element of N and for all values of the parameters alpha > - 1 and beta > - 1. It turns out that this number depends essentially on alpha and beta as well as on the specific normalization of the function Q(n)((alpha, beta)) (x). Interlacing properties of the zeros are also obtained. As a consequence of the main result, we determine the number of zeros of Laguerre's and Hermite's functions of second kind. (c) 2005 Elsevier B.V. All rights reserved.

On a symmetry in strong distributions

A strong Stieltjes distribution d psi(t) is called symmetric if it satisfies the propertyt(omega) d psi(beta(2)/t) = -(beta(2)/t)(omega) d psi(t), for t is an element of (a, b) subset of or equal to (0, infinity), 2 omega is an element of Z, and beta > 0.In this article some consequences of symmetry on the moments, the orthogonal L-polynomials and the quadrature formulae associated with the distribution are given. (C) 1999 Elsevier B.V. B.V. All rights reserved.

Monotonicity of zeros of Jacobi-Sobolev type orthogonal polynomials

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Crystallization and preliminary X-ray diffraction analysis of the catalytic subunit of ADP-glucose pyrophosphorylase from potato tuber

ADP-glucose pyrophosphorylase is the key regulatory enzyme in the biosynthesis of starch in plants and glycogen in bacteria. The enzyme from potato tuber is comprised of a regulatory subunit and a catalytic subunit and is present as a heterotetramer (alpha(2)beta(2)) the catalytic subunit from potato tuber (50 kDa) was crystallized in four different forms, two of which are suitable for structural studies. A tetragonal crystal form obtained in the presence of the substrate analog Cr-ATP diffracted to 2.2 Angstrom and belongs to space group P4(1) (or its enantiomorph), with unit-cell parameters a = b = 110.57, c = 190.14 Angstrom. A second crystal form obtained diffracted to 2.8 Angstrom and belongs to space group PZ, with unit-eel parameters a = 80.06, b = 138.84, c = 92.20 Angstrom, beta = 112.40 degrees. As this protein displays no significant homology to any currently known protein structure, a search for heavy-atom derivatives has been initiated.

ABSOLUTE NEUTRIONO MASS FROM HELICITY MEASUREMENTS

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Search for Pair Production of First-Generation Scalar Leptoquarks in pp Collisions at root s=7 TeV

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Search for Pair Production of Second-Generation Scalar Leptoquarks in pp Collisions at root s=7 TeV

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Virasoro constraints and flavor-topology duality in QCD

We derive Virasoro constraints for the zero momentum part of the QCD-like partition functions in the sector of topological charge v. The constraints depend on the topological charge only through the combination N-f +betav/2 where the value of the Dyson index beta is determined by the reality type of the fermions. This duality between flavor and topology is inherited by the small-mass expansion of the partition function and all spectral sum rules of inverse powers of the eigenvalues of the Dirac operator. For the special case beta =2 but arbitrary topological charge the Virasoro constraints are solved uniquely by a generalized Kontsevich model with the potential V(X) = 1/X.

Anticardiolipin antibodies from syphilis and systemic lupus erythematosus induce leakage in cardiolipin vesicles

Anticardiolipin antibodies from sera of patients with systemic lupus erythematosus or syphilis induced leakage of entrapped carboxyfluorescein (CF) from cardiolipin (CL)/phosphatidylcholine(PC) vesicles prepared by sonication of equimolar mixtures of CL:PC. The sera dilution used here was 1:7500. IgG (5-20 mu g/ml) from the same sera, not containing beta(2)GPI, also produced a concentration-dependent leak. Vesicle leakage was inhibited by salt and was not detected with vesicles prepared exclusively with phosphatidylcholine. The demonstration of antibody-induced vesicle leakage offers a convenient system to investigate the mechanism of antibody-lipid binding as well as a potential diagnostic tool.