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Neuropeptide Y (NPY) is a powerful vasoconstrictor in vivo but is usually much less active on isolated blood vessels. The contractile effect of NPY was examined in the isolated rat femoral artery exposed to various degrees of vasoconstriction. The effects of NPY on the relaxation induced by vasodilator agents was also studied. NPY (< or = 1 microM) had no contractile effect. In vessels pretreated

We have compared the effects of vasoactive intestinal peptide (VIP) and of the VIP-related peptides pituitary adenylate cyclase activating peptide (PACAP) 1-27 and 1-38, helodermin, helospectin I and helospectin II, on the electrically evoked twitches in the isolated vas deferens of the rat. While VIP was virtually without effect, PACAP 1-38 suppressed the electrically evoked twitches effectively

1. In the present study we compared neuropeptide Y (NPY) and NPY-related analogues for their ability to activate or bind to vascular NPY receptors in four experimental set-ups. Previous results have suggested the existence of different receptor subtypes, Y1 receptors requiring full-length NPY (1-36) or [Pro34]-NPY, and Y2 receptors recognizing also N-terminally truncated forms of NPY but not [Pro3

1. Neuropeptide Y (NPY) and peptide YY (PYY) seem to act on at least two receptor subtypes, Y1 and Y2. The Y1-receptor requires the whole C-terminally amidated NPY/PYY molecule whereas the Y2-receptor in addition recognizes C-terminal fragments of the two peptides. The present study was designed to elucidate whether NPY and related peptides were able to release histamine from isolated peritoneal m

Neuropeptide Y (NPY) is a well-established vasopressor agent present in sympathetic perivascular nerves. Recently, it was found that high doses of the peptide cause a biphasic pressor-depressor response upon intravenous administration. We now report that C-terminal NPY fragments (NPY-(18-36) and NPY-(22-36] given intravenously to conscious or pithed (areflexive) male Sprague-Dawley rats mimic the

Microinjection of neuropeptide Y (NPY) into the nucleus tractus solitarius (NTS) induces an initial and reversible fall in arterial pressure (AP) and heart rate (HR), along with a delayed and long-lasting blockade of cardiovascular responses to L-glutamate (L-Glu) injected into the same site and an inhibition of the baroreflex arc. By injecting NPY-receptor subtype selective agonists and NPY-relat

Neuropeptide Y (NPY) microinjected unilaterally into the nucleus tractus solitarii (NTS) of anesthetized paralyzed rats elicits a gradual dose-dependent and reversible fall in arterial pressure (AP) and heart rate (HR) lasting 20 min. It also abolished the brief (less than 1 min) dose-dependent and reversible fall of AP and HR elicited by L-glutamate (L-Glu) injected into the nucleus. The blockade

1. The effects of various neuropeptide Y (NPY) and peptide YY (PYY) fragments on electrically-evoked twitches in the rat isolated vas deferens were studied and compared with the effects of full length NPY and PYY. The aim was to identify the shortest NPY/PYY fragments that are capable of suppressing the contractions. 2. NPY (1-36) and C-terminal fragments of NPY (from 11-36 to 22-36) suppressed th

1. Helodermin, helospectin I and helospectin II, peptides recently isolated from the salivary gland venom of Heloderma suspectum, were compared to vasoactive intestinal peptide (VIP) with respect to effects on systemic blood pressure and on isolated femoral arteries in the rat. 2. They all reduced blood pressure in a dose-dependent manner; helodermin was less effective than VIP. However, at doses

The effects of neuropeptide Y (NPY) on systemic arterial blood pressure and heart rate were studied in anesthetized intact and pithed rats. I.v. doses of NPY (0.3-30 nmol/kg) raised the mean arterial blood pressure dose dependently. At doses of greater than or equal to 3.0 nmol/kg, the initial pressor response was followed by a dose-dependent fall in blood pressure in intact and pithed rats. The d

1. In the present study we have examined whether neuropeptide Y (NPY) interferes with non-adrenergic, non-cholinergic nerve-mediated contractions and relaxations in the guinea-pig airways. In these experiments we have used ring preparations of bronchi and trachea, incubated in the presence of atropine, propranolol and indomethacin (each 1 microM). 2. The contractile response to electrical stimulat

Heterogeneity among NPY (and PYY) receptors was first proposed on the basis of studies on sympathetic neuroeffector junctions, where NPY (and PYY) can exert three types of action: 1) a direct (e.g., vasoconstrictor) response; 2) a postjunctional potentiating effect on NE-evoked vasoconstriction; and 3) a prejunctional suppression of stimulated NE release; the two latter phenomena are probably reci

The effects of neuropeptide Y (NPY) on the contractile response to vagus nerve stimulation at different frequencies was studied in an isolated tracheal tube preparation from guinea pig. NPY had no effect on basal smooth muscle tension or on the contractile effect of carbachol, but inhibited vagally induced contractions in a concentration-dependent manner with a greater inhibition at low frequencie

The Advanced Light Source (ALS) at Berkeley Lab has seen many upgrades over the years, keeping it one of the brightest sources for soft x-rays worldwide. Recent developments in magnet technology and lattice design appear to open the door for very large further increases in brightness [1], particularly by reducing the horizontal emittance, even within the space constraints of the existing tunnel. I

Fast kicker systems are required for the proposed upgrade of ALS to a diffraction-limited light source (ALS-U). The main approach is to have multiple stripline kicker magnets driven by inductive adders. The design details of the kicker structures and the inductive adder options will be discussed.

The Advanced Light Source (ALS) at Berkeley Lab has seen many upgrades over the years, keeping it one of the brightest sources for soft x-rays worldwide. Recent developments in magnet and vacuum technology, as well as lattice design (multi bend achromat lattices) appear to open the door for very large further increases in brightness [1]. This could be achieved by reducing the horizontal emittance,

An overview of the design of compact elliptically polar-izing undulator with small round magnetic gap to provide full polarization control of synchrotron radiation in a more cost effective manner and consuming less built in space than the state of the art devices. This type of undulator is meant as source for the potential future Soft X-ray (SXL) FEL beamline using the linear accelerator at MAX IV