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O E Brodde - One of the best experts on this subject based on the ideXlab platform.
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Physiology and pharmacology of cardiovascular Catecholamine Receptors: implications for treatment of chronic heart failure.
American heart journal, 1990Co-Authors: O E BroddeAbstract:In the sympathetic nervous system the physiologic effects of the endogenous Catecholamines noradrenaline (NA) and adrenaline (A) are mediated by alpha- and beta-adrenoReceptors (ARs). Both AR-types can be subdivided into two major subtypes: alpha-ARs into alpha-1 (predominant effect: vasoconstriction) and alpha-2 (presynaptic: inhibition of NA-release; postsynaptic: vasoconstriction), beta-ARs into beta-1 (cardiac effects, renal renin release, and lipolysis) and beta-2 (presynaptic: facilitation of NA-release; postsynaptic: vascular, bronchial, and uterine smooth muscle relaxation, glycogenolysis and possibly part of the A-mediated cardiac effects). During the last 30 years growing evidence has accumulated that dopamine (DA), the third endogenous Catecholamine and the immediate precursor of NA, may also cause peripheral effects through stimulation of specific DA-Receptors, in addition to its known action at alpha- and beta-ARs. It is now well accepted that at least two different DA-Receptors are present in many peripheral tissues (DA1 and DA2), including those of the cardiovascular and autonomic nervous system. They seem to be involved in dilation of certain vascular beds, inhibition of NA-release during nerve stimulation, natriuresis, and aldosterone release. In chronic heart failure cardiac beta-AR function decreases (presumably due to endogenous "down-regulation" by the elevated Catecholamines), and this decrease is related to the severity of heart failure (judged clinically by New York Heart Association functional class). The human heart contains both functional beta-1 and beta-2 ARs; cardiac beta-1 and beta-2 ARs seem to be differentially affected by different kinds of heart failure; in end-stage dilated cardiomyopathy beta-1 ARs are selectively reduced, whereas beta-2 ARs are nearly normal.(ABSTRACT TRUNCATED AT 250 WORDS)
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Physiology and pharmacology of cardiovascular Catecholamine Receptors: Implications for treatment of chronic heart failure
American Heart Journal, 1990Co-Authors: O E BroddeAbstract:Abstract In the sympathetic nervous system the physiologic effects of the endogenous Catecholamines noradrenaline (NA) and adrenaline (A) are mediated by α- and β-adrenoReceptors (ARs). Both AR-types can be subdivided into two major subtypes: α-ARs into α-1 (predominant effect: vasoconstriction) and α-2 (presynaptic: inhibition of NA-release; postsynaptic: vasoconstriction), β-ARs into β-1 (cardiac effects, renal renin release, and lipolysis) and β-2 (presynaptic: facilitation of NA-release; postsynaptic: vascular, bronchial, and uterine smooth muscle relaxation, glycogenolysis and possibly part of the A-mediated cardiac effects). During the last 30 years growing evidence has accumulated that dopamine (DA), the third endogenous Catecholamine and the immediate precursor of NA, may also cause peripheral effects through stimulation of specific DA-Receptors, in addition to its known action at α- and β-ARs. It is now well accepted that at least two different DA-Receptors are present in many peripheral tissues (DA 1 and DA 2 ), including those of the cardiovascular and autonomic nervous system. They seem to be involved in dilation of certain vascular beds, inhibition of NA-release during nerve stimulation, natriuresis, and aldosterone release. In chronic heart failure cardiac β-AR function decreases (presumably due to endogenous "down-regulation" by the elevated Catecholamines), and this decrease is related to the severity of heart failure (judged clinically by New York Heart Association functional class). The human heart contains both functional β-1 and β-2 ARs; cardiac β-1 and β-2 ARs seem to be differentially affected by different kinds of heart failure; in end-stage dilated cardiomyopathy β-1 ARs are selectively reduced, whereas β-2 ARs are nearly normal. Under these (pathologic) conditions β-2 ARs may substitute for the loss in β-1 AR function, thereby maintaining contractility, at least partially. In mitral valve disease and end-stage ischemic cardiomyopathy, on the other hand, the decrease in cardiac β-AR function is due to a concomitant decrease in β-1 and β-2 ARs. However, very little is known about changes in α-ARs and DA-Receptors in chronic heart failure. Epinine (N-metyl-DA), the active metabolite of ibopamine, is a full agonist at DA 1 and DA 2 Receptors with an affinity equal to or even slightly higher than DA. Similarly, its affinity to α-1 and α-2 as well as to β-1 ARs is comparable with DA, whereas at β-2 ARs the affinity of epinine is about 10 times higher than that of DA. In addition, epinine induces in isolated electrically driven human right atria its positive inotropic effect via stimulation of β-1 and β-2 ARs (being a full agonist), whereas DA is a partial agonist acting solely at β-1 ARs. Thus long-term application of ibopamine (i.e. epinine) should lead to the following cardiovascular and endocrine effects: it should cause positive inotropic effects through stimulation of cardiac β-1 and β-2 ARs, direct vasodilation through stimulation of β-2 ARs and DA 1 Receptors, indirect vasodilation through stimulation of presynaptic DA 2 Receptors and α-2 ARs (which leads to inhibition of NA-release), diuresis and natriuresis through stimulation of (renal) DA 1 Receptors. Blood pressure may increase slightly (but only at higher doses) via stimulation of postsynaptic α-1 and α-2 ARs. Thus the properties of epinine may be a suitable combination of effects to treat patients with chronic heart failure, provided that downregulation of receptor function can be prevented.
Tom Defoirdt - One of the best experts on this subject based on the ideXlab platform.
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The Catecholamine stress hormones norepinephrine and dopamine increase the virulence of pathogenic Vibrio anguillarum and Vibrio campbellii.
FEMS microbiology ecology, 2014Co-Authors: Gde Sasmita Julyantoro Pande, Nguyen Thao Suong, Peter Bossier, Tom DefoirdtAbstract:Obtaining a better understanding of mechanisms involved in bacterial infections is of paramount importance for the development of novel agents to control disease caused by (antibiotic resistant) pathogens in aquaculture. In this study, we investigated the impact of Catecholamine stress hormones on growth and virulence factor production of pathogenic vibrios (i.e. two Vibrio campbellii strains and two Vibrio anguillarum strains). Both norepinephrine and dopamine (at 100 mu M) significantly induced growth in media containing serum. The compounds also increased swimming motility of the tested strains, whereas they had no effect on caseinase, chitinase, and hemolysin activities. Further, antagonists for eukaryotic Catecholamine Receptors were able to neutralize some of the effects of the Catecholamines. Indeed, the dopaminergic receptor antagonist chlorpromazine neutralized the effect of dopamine, and the a-adrenergic receptor antagonists phentolamine and phenoxybenzamine neutralized the effect of norepinephrine, whereas the beta-adrenergic receptor antagonist propranolol had limited to no effect. Finally, pretreatment of pathogenic V. campbellii with Catecholamines significantly increased its virulence toward giant freshwater prawn larvae. However, the impact of Catecholamine receptor antagonists on in vivo virulence was less clear-cut when compared to the in vitro experiments. In summary, our results show that - similar to enteric pathogens - Catecholamines also increase the virulence of vibrios that are pathogenic to aquatic organisms by increasing motility and growth in media containing serum.
Marvin A Sorianoursua - One of the best experts on this subject based on the ideXlab platform.
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design synthesis and in vitro evaluation of a dopa organoboron compound that acts as a bladder relaxant through non Catecholamine Receptors
Molecular Diversity, 2019Co-Authors: Ana L Ocamponestor, R M Lopezmayorga, E F Castillohenkel, Itzia I Padillamartinez, Jose G Trujilloferrara, Marvin A SorianoursuaAbstract:Bladder relaxation through drug administration is an interesting topic in medicinal and combinatorial chemistry. In fact, compounds targeting Catecholamine Receptors [dopamine Receptors and beta-adrenergic Receptors (βAR) expressed in the bladder] are among the compounds commonly employed for this purpose. In particular, recent investigations have tended to focus on the β3-adrenoceptor (β3AR) as a target in the treatment of urinary incontinence and other disorders. However, organoboron compounds have been suggested as potent and efficient agents on these drug targets. In this work, through a docking study, we identified the parameters that induce a theoretical improvement in the affinity and activity of the organoboron compounds on the Catecholamine Receptors expressed in the bladder. Then, the identified potential drug, a boron-containing dopa-derivative named DPBX-l-Dopa, was synthesized and characterized. This compound induces a relaxation on the smooth muscle of the rat bladder, behaving as a weak relaxant compared to isoproterenol but with similar efficacy to BRL377, a selective β3AR agonist. However, unexpectedly, this effect was not blocked by propranolol or haloperidol at the concentrations at which they are able to block the Catecholamine Receptors in bladder tissue. In view of these results, the effect of DPBX-l-Dopa compound on the alpha 1 adrenergic Receptors (α1AR) of aorta of the rats was also explored; however, no response of the tissue to this compound was obtained. The possible mechanisms of the action of this compound were explored and are discussed further.
Patrick T. Horn - One of the best experts on this subject based on the ideXlab platform.
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Studies on the location of Catecholamine Receptors in canine sympathetic ganglia.
European journal of pharmacology, 1992Co-Authors: Patrick T. Horn, Jai D. KohliAbstract:Abstract Receptors mediating Catecholamine-induced inhibition were studied in cardiac ganglia of pentobarbital-anesthetized dogs. Using selective agonists and antagonists the presence of three receptor subtypes was verified: α 1 - and α 2 -adrenoceptors and dopamine D 2 Receptors. Activation of α 1 -adrenoceptors or dopamine D 2 Receptors reduced the response to preganglionic nerve stimulation but not to direct stimulation of the nicotinic acetylcholine Receptors of the principal ganglion cells: response to both types of stimulation were reduced by activation of ganglionic α 2 -adrenoceptors. These results suggested that two inhibitory systems were present in canine sympathetic ganglia and mediated the effects of exogenous Catecholamines. One system involved α 1 -adrenoceptors and dopamine D 2 Receptors located proximal to the synapse of the pre- and postganglionic neurons and the other involved α 2 -adrenoceptors located distal to the intraganglionic synapse.
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Dopamine receptor agonists in cardiovascular medicine
Trends in cardiovascular medicine, 1991Co-Authors: Patrick T. Horn, Michael B. MurphyAbstract:The cardiovascular and renal effects of dopamine are mediated through peripheral Catecholamine Receptors. Knowledge of the receptor type responsible for each of the actions of dopamine leads to its rational use clinically and to understanding the hemodynamic actions of the newer dopamine receptor agonists recently introduced into clinical trials. Several of the newer agonists have profiles of receptor activities that differ from dopamine, and early clinical studies indicate that they will have different therapeutic indications and applications.
Gde Sasmita Julyantoro Pande - One of the best experts on this subject based on the ideXlab platform.
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The Catecholamine stress hormones norepinephrine and dopamine increase the virulence of pathogenic Vibrio anguillarum and Vibrio campbellii.
FEMS microbiology ecology, 2014Co-Authors: Gde Sasmita Julyantoro Pande, Nguyen Thao Suong, Peter Bossier, Tom DefoirdtAbstract:Obtaining a better understanding of mechanisms involved in bacterial infections is of paramount importance for the development of novel agents to control disease caused by (antibiotic resistant) pathogens in aquaculture. In this study, we investigated the impact of Catecholamine stress hormones on growth and virulence factor production of pathogenic vibrios (i.e. two Vibrio campbellii strains and two Vibrio anguillarum strains). Both norepinephrine and dopamine (at 100 mu M) significantly induced growth in media containing serum. The compounds also increased swimming motility of the tested strains, whereas they had no effect on caseinase, chitinase, and hemolysin activities. Further, antagonists for eukaryotic Catecholamine Receptors were able to neutralize some of the effects of the Catecholamines. Indeed, the dopaminergic receptor antagonist chlorpromazine neutralized the effect of dopamine, and the a-adrenergic receptor antagonists phentolamine and phenoxybenzamine neutralized the effect of norepinephrine, whereas the beta-adrenergic receptor antagonist propranolol had limited to no effect. Finally, pretreatment of pathogenic V. campbellii with Catecholamines significantly increased its virulence toward giant freshwater prawn larvae. However, the impact of Catecholamine receptor antagonists on in vivo virulence was less clear-cut when compared to the in vitro experiments. In summary, our results show that - similar to enteric pathogens - Catecholamines also increase the virulence of vibrios that are pathogenic to aquatic organisms by increasing motility and growth in media containing serum.