Vasoactive

Vasoactive and Psychoactive Amines and Alkaloids Most compounds produciag hypertensive episodes are classified as amines and are found ia greatest coaceatratioa ia banana, plantain, tomato, avocado, piaeapple, broad beans, and various cheeses. Amines that are vasoactive iaclude dopamine [31-61-6], CgH N02 tyramine (11) histamine [31-43-6], tryptamine [61-34-1], C2QH22N2 noradrenaline [31-41-2], CgH NO and... 

Patients receiving monoamine oxidase inhibitors (MAOI) as antidepressant therapy have been especially subject to the hypertensive effects of vasoactive amines (52). These dietary amines have also been impHcated as causative agents ia migraine. Other aaturaHy occurring alkaloids (qv) have been recognized for centuries as possessing neurological stimulant and depressant properties. 

Melatonin [73-31-4] C 2H N202 (31) has marked effects on circadian rhythm (11). Novel ligands for melatonin receptors such as (32) (12), C2yH2gN202, have affinities in the range of 10 Af, and have potential use as therapeutic agents in the treatment of the sleep disorders associated with jet lag. Such agents may also be usehil in the treatment of seasonal affective disorder (SAD), the depression associated with the winter months. Histamine (see Histamine and histamine antagonists), adenosine (see Nucleic acids), and neuropeptides such as corticotropin-like intermediate lobe peptide (CLIP) and vasoactive intestinal polypeptide (VIP) have also been reported to have sedative—hypnotic activities (7). 

CGRP is widely distributed throughout the peripheral and central nervous systems and is found ia sensory neurons and ia the autonomic and enteric nervous systems. In many iastances CGRP is co-localized with other neuroregulators, eg, ACh ia motor neurons, substance P, somatostatin, vasoactive intestinal polypeptide (VIP), and galanin ia sensory neurons. It is also present ia the CNS, with ACh ia the parabigeminal nucleus and with cholecystokinin (CCK) ia the dorsal parabrachial area. CGRP functions as a neuromodulator or co-transmitter. 

Vasoactive Intestinal Peptide and Pituitary Adenylate Cyclase Activating Peptide. Vasoactive intestinal peptide (VIP)... 

USP (Sandostatiu) flutamide (Rulexin) [13311-84-7] C11H11F3N2O3 276.21 (66) tumors vasoactive intestinal peptide-secretory tumors metastatic prostatic stools vomit-ing abdomiaal pain pain on iujection diarrhea... 

Compounds that induce bronchoconstriction include tobacco smoke, formaldehyde, and diethyl ether. Several other compounds, such as acidic fumes (e.g., sulfuric acid) and gases, such as ozone and nitrogen dioxide, as well as isocyanates, can cause bronchoconstriction. Also, cellular damage in the airways induces bronchoconstriction because of the release of vasoactive compounds. Frequently, different mechanisms work at the same time, provoking bronchoconstriction and increased secretion of mucus, both of which interfere with respiration. 

Biological function and chemistry of endothelin, vasoactive peptide with macro-cyclic fragments formed by disulfide bridges between cysteine residues 99CCC1211. 

Because renal vasodilatation and hyperfiltration are often associated with a natriuretic response, a number of activators or inhibitors of endogenous vasoactive systems can cause increased NaCl excretion, and some of these may be developed into compounds of clinical interest in special situations. Such agents include natriuretic pqDtides most notably B-type natriuretic peptide (nesiritide), neutral endopeptidase (NEP) inhibitors (thiorphan, phosphoramidon), mixed NEP and ACE inhibitors (omapatrilat), guanylin and uroguanylin, kinins, prostaglandins of the E series, adrenomedullin, relaxin, prolactin, and others. 

Endothelins comprise a family of three vasoactive isopeptides of 21 amino acids that have an essential role in the regulation of the vascular and bronchiolar tone and the control of natriuresis in the kidney. Endothelin peptides are also involved in nociception and have a critical role in the progression of prostate and ovarian cancer. 

Ubiquitous mitochondrial monoamine oxidase [monoamine oxygen oxidoreductase (deaminating) (flavin-containing) EC 1.4.3.4 MAO] exists in two forms, namely type A and type B [ monoamine oxidase (MAO) A and B]. They are responsible for oxidative deamination of primary, secondary, and tertiary amines, including neurotransmitters, adrenaline, noradrenaline, dopamine (DA), and serotonin and vasoactive amines, such as tyramine and phenylethylamine. Their nonselec-tive and selective inhibitors ( selective MAO-A and -B inhibitors) are employed for the treatment of depressive illness and Parkinson s disease (PD). 

Pituitary Adenylyl Cyclase-activating Polypeptide (PACAP) is a 38-amino acid peptide (PACAP-38), which is widely expressed in the central nervous system. PACAP is most abundant in the hypothalamus. It is also found in the gastrointestinal tract, the adrenal gland and in testis. Its central nervous system functions are ill-defined. In the periphery, PACAP has been shown to stimulate catecholamine secretion from the adrenal medulla and to regulate secretion from the pancreas. Three G-protein coupled receptors have been shown to respond to PACAP, PAQ (PACAP type I) specifically binds PACAP, VPACi and VPAC2 also bind vasoactive intestinal peptide (VDP). Activation of PACAP receptors results in a Gs-mediated activation of adenylyl cyclase. 

ATP with acetylcholine and vasoactive intestinal peptide in some parasympathetic nerves... 

Vasoactive Intestinal Peptide(VIP) is a 28-amino acid peptide, which has a variety of actions as a neuroendocrine hormone and a putative neurotransmitter. It... 

VIPoma stands for vasoactive intestinal polypeptide-secreting tumour. VIPomas are rare neuroendocrine tumours located in the pancreas. 

There are also other immimological mechanisms, especially via IgG or IgM antibodies with immune complex formation, which can lead to similar clinical conditions [20, 34, 42] as has been shown in dextran anaphylaxis (table 1). Triggering of mast cells and basophils leads to release of various vasoactive mediators, among which histamine was the first recognized in 1908 (fig. 3,4) [6]. 

We have identified mast cells around blood vessels and between myocardial fibers in all sections of human hearts [16,17]. These cells are also seen in normal and atherosclerotic human arterial intima [ 18-21 ]. In situ electron microscopy of cardiac mast cells revealed a small percentage (about 5%) of activated, i.e. partially degranulated mast cells [16,22]. This is clinically relevant because it implies that immunologic and non-immunologic stimuli can activate HHMC to release vasoactive and proinflammatory mediators [23]. 

Cysteinyl leukotrienes can induce an early, transient fall in arterial pressure associated with sympathoadrenergic activation, plus a late rise in small coronary arteriolar resistance [32]. Using specific antagonists of CysFTi and CysFT2 [63] it will be possible to assess the each receptor s contribution to the cardiovascular effects of these vasoactive mediators. 

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