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Bachmann P, Zhang X, Larra MF, Rebeck D, Schönbein K, Koch KP, Schächinger H. Validation of an automated bilateral feet cold pressor test. Int J Psychophysiol 2018; 124:62-70. [DOI: 10.1016/j.ijpsycho.2017.10.013] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2017] [Revised: 10/28/2017] [Accepted: 10/31/2017] [Indexed: 12/21/2022]
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2
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Mehrotra S, Gupta S, Chan KY, Villalón CM, Centurión D, Saxena PR, MaassenVanDenBrink A. Current and prospective pharmacological targets in relation to antimigraine action. Naunyn Schmiedebergs Arch Pharmacol 2008; 378:371-94. [PMID: 18626630 DOI: 10.1007/s00210-008-0322-7] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2008] [Accepted: 06/06/2008] [Indexed: 05/10/2023]
Abstract
Migraine is a recurrent incapacitating neurovascular disorder characterized by unilateral and throbbing headaches associated with photophobia, phonophobia, nausea, and vomiting. Current specific drugs used in the acute treatment of migraine interact with vascular receptors, a fact that has raised concerns about their cardiovascular safety. In the past, alpha-adrenoceptor agonists (ergotamine, dihydroergotamine, isometheptene) were used. The last two decades have witnessed the advent of 5-HT(1B/1D) receptor agonists (sumatriptan and second-generation triptans), which have a well-established efficacy in the acute treatment of migraine. Moreover, current prophylactic treatments of migraine include 5-HT(2) receptor antagonists, Ca(2+) channel blockers, and beta-adrenoceptor antagonists. Despite the progress in migraine research and in view of its complex etiology, this disease still remains underdiagnosed, and available therapies are underused. In this review, we have discussed pharmacological targets in migraine, with special emphasis on compounds acting on 5-HT (5-HT(1-7)), adrenergic (alpha(1), alpha(2,) and beta), calcitonin gene-related peptide (CGRP(1) and CGRP(2)), adenosine (A(1), A(2), and A(3)), glutamate (NMDA, AMPA, kainate, and metabotropic), dopamine, endothelin, and female hormone (estrogen and progesterone) receptors. In addition, we have considered some other targets, including gamma-aminobutyric acid, angiotensin, bradykinin, histamine, and ionotropic receptors, in relation to antimigraine therapy. Finally, the cardiovascular safety of current and prospective antimigraine therapies is touched upon.
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Affiliation(s)
- Suneet Mehrotra
- Division of Vascular Pharmacology, Department of Internal Medicine, Erasmus MC, University Medical Center Rotterdam, P.O. Box 2040, 3000 CA, Rotterdam, The Netherlands
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3
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Tobler PN, O'Doherty JP, Dolan RJ, Schultz W. Reward value coding distinct from risk attitude-related uncertainty coding in human reward systems. J Neurophysiol 2006; 97:1621-32. [PMID: 17122317 PMCID: PMC2637604 DOI: 10.1152/jn.00745.2006] [Citation(s) in RCA: 363] [Impact Index Per Article: 20.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
When deciding between different options, individuals are guided by the expected (mean) value of the different outcomes and by the associated degrees of uncertainty. We used functional magnetic resonance imaging to identify brain activations coding the key decision parameters of expected value (magnitude and probability) separately from uncertainty (statistical variance) of monetary rewards. Participants discriminated behaviorally between stimuli associated with different expected values and uncertainty. Stimuli associated with higher expected values elicited monotonically increasing activations in distinct regions of the striatum, irrespective of different combinations of magnitude and probability. Stimuli associated with higher uncertainty (variance) elicited increasing activations in the lateral orbitofrontal cortex. Uncertainty-related activations covaried with individual risk aversion in lateral orbitofrontal regions and risk-seeking in more medial areas. Furthermore, activations in expected value-coding regions in prefrontal cortex covaried differentially with uncertainty depending on risk attitudes of individual participants, suggesting that separate prefrontal regions are involved in risk aversion and seeking. These data demonstrate the distinct coding in key reward structures of the two basic and crucial decision parameters, expected value, and uncertainty.
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Affiliation(s)
- Philippe N Tobler
- Department of Physiology, Development and Neuroscience, University of Cambridge, Downing Street, Cambridge CB2 3DY, UK.
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Tobler PN, O'doherty JP, Dolan RJ, Schultz W. Human neural learning depends on reward prediction errors in the blocking paradigm. J Neurophysiol 2005; 95:301-10. [PMID: 16192329 PMCID: PMC2637603 DOI: 10.1152/jn.00762.2005] [Citation(s) in RCA: 127] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Learning occurs when an outcome deviates from expectation (prediction error). According to formal learning theory, the defining paradigm demonstrating the role of prediction errors in learning is the blocking test. Here, a novel stimulus is blocked from learning when it is associated with a fully predicted outcome, presumably because the occurrence of the outcome fails to produce a prediction error. We investigated the role of prediction errors in human reward-directed learning using a blocking paradigm and measured brain activation with functional magnetic resonance imaging. Participants showed blocking of behavioral learning with juice rewards as predicted by learning theory. The medial orbitofrontal cortex and the ventral putamen showed significantly lower responses to blocked, compared with nonblocked, reward-predicting stimuli. In reward-predicting control situations, deactivation in orbitofrontal cortex and ventral putamen occurred at the time of unpredicted reward omissions. Responses in discrete parts of orbitofrontal cortex correlated with the degree of behavioral learning during, and after, the learning phase. These data suggest that learning in primary reward structures in the human brain correlates with prediction errors in a manner that complies with principles of formal learning theory.
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Affiliation(s)
- Philippe N Tobler
- Department of Anatomy, University of Cambridge, Cambridge CB2 3DY, UK.
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Matsumoto K, Yoshida M, Andersson KE, Hedlund P. Effects in vitro and in vivo by apomorphine in the rat corpus cavernosum. Br J Pharmacol 2005; 146:259-67. [PMID: 16025145 PMCID: PMC1576267 DOI: 10.1038/sj.bjp.0706317] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2005] [Revised: 05/03/2005] [Accepted: 05/24/2005] [Indexed: 11/10/2022] Open
Abstract
The study was performed to clarify if apomorphine at the level of the rat corpus cavernosum can produce erectile responses or interfere with nerve-induced penile erection. Apomorphine (10(-9)-10(-4) M) exhibited a 10-fold higher potency to relax phenylephrine (Phe)- than endothelin-1 (ET-1)-induced contractions. Relaxant effects of apomorphine in Phe-activated corpus cavernosum did not change tissue levels of cyclic nucleotides, and were unaffected by inhibition of the synthesis of nitric oxide, or by inhibition of the soluble guanylate cyclase. Relaxations by apomorphine of ET-1-contracted rat corpus cavernosum were not influenced by alpha2-adrenoceptor blockade (yohimbine, 10(-7) M), or by the dopamine D1-like receptor antagonist SCH 23390 (10(-6) M). Clozapine (10(-6) M), a proposed dopamine D2-like receptor antagonist, partly reduced apomorphine-induced relaxations, and significantly altered the -log IC50 value for apomorphine. Nerve-induced contractions of the rat corpus cavernosum were attenuated by apomorphine in a concentration-dependent and biphasic manner. Yohimbine (10(-7) M) abolished the biphasic concentration-response pattern. SCH 23390 (10(-6) M) attenuated the inhibitory effects of apomorphine on contractions, and significantly altered the -log IC50 value for the compound. In anesthetized rats (50 mg kg(-1) pentobarbital sodium, 10 mg kg(-1) ketamine), intracavernous apomorphine (100, 300, or 1000 nmol) did not have effects on basal cavernous pressure under resting conditions, and did not affect filling or emptying rates, or peak pressures of the rat corpus cavernosum during submaximal activation of the cavernous nerve. In awake rats, apomorphine produced a maximal number of erections at 300 nmol kg(-1). In the rat isolated corpus cavernosum, pre- and postjunctional effects of apomorphine appear to involve dopamine D1- and D2-like receptors, as well as alpha-adrenoceptors. At relevant systemic doses of apomorphine, peripheral effects of the compound are unlikely to contribute to its proerectile effects in rats.
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Affiliation(s)
- Kenshi Matsumoto
- Department of Clinical and Experimental Pharmacology, Lund University Hospital, Lund S-221 85, Sweden
- Department of Urology, Kumamoto University School of Medicine, Kumamoto, Japan
| | - Masaki Yoshida
- Department of Urology, Kumamoto University School of Medicine, Kumamoto, Japan
| | - Karl-Erik Andersson
- Department of Clinical and Experimental Pharmacology, Lund University Hospital, Lund S-221 85, Sweden
| | - Petter Hedlund
- Department of Clinical and Experimental Pharmacology, Lund University Hospital, Lund S-221 85, Sweden
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Murphy EJ. Intra-arterial injection of metoclopramide, midazolam, propofol and pethidine. Anaesth Intensive Care 2002; 30:367-9. [PMID: 12075648 DOI: 10.1177/0310057x0203000318] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
A case is reported in which metoclopramide, midazolam, propofol, and pethidine were injected arterially during the course of anaesthesia, resulting in oedema and discolouration of the hand initially, but no long-term sequelae. An AVI 470 pump (3M Corporation) was used to control the infusion, andprevented backflow through a cannula which was unintentionally sited in an artery rather than a vein. Few anaesthetic drugs have their effects well documented when given arterially, and in particular, there were no previous reported cases involving metoclopramide in this context. The pharmacology of metoclopramide is discussed with reference to the drug's known effects on vascular beds and platelet function.
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Affiliation(s)
- E J Murphy
- Freeman Hospital, High Heaton, Newcastle-upon Tyne, United Kingdom
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Ricci A, Amenta F, Bronzetti E, Felici L, Hussain T, Lokhandwala MF. Age-related changes of dopamine receptor protein immunoreactivity in the rat mesenteric vascular tree. Mech Ageing Dev 2002; 123:537-46. [PMID: 11796139 DOI: 10.1016/s0047-6374(01)00361-x] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Dopamine D1-D5 receptor protein immunoreactivity and tyrosine hydroxylase (TH) immunoreactivity were investigated on the mesenteric arterial tree by immunohistochemistry. The density of various dopamine receptors and TH immunoreactivity was compared between young (6-month-old), adult (15-month-old) and senescent (24-month-old) Fischer 344 rats by computer-assisted microdensitometry. The dopamine D1-like (D1 and D5) receptors were localized on the tunica media of different sized mesenteric artery branches. The D2-like (D2, D3 and D4) receptors as well as TH immunoreactivity were localized only on the adventitia-media transitional zone of mesenteric arterial tree. Expression of the D1 and D5 receptors was decreased in both adult and senescent rats compared to the young rats, suggesting an age-related decline in these receptors. Of the D2-like receptors, the expression of the D2 receptor was decreased as a function of age, while the D3 receptor was unchanged in the senescent rats compared to the young rats. Expression of the D4 receptor was increased in adult, but was unchanged in the senescent rats compared to young animals. TH immunoreactivity was increased as a function of age. The above data suggest that reduction in the D1, D2 and D5 receptor expression may contribute to the deficiency in the dopamine-mediated vasorelaxation and hence blood flow in the mesenteric vascular tree in aging. The different sensitivity to aging of sympathetic neuroeffector junctions labeled by TH and of dopamine D2-like receptors that are known to be prejunctional, suggests that age-related changes of dopamine receptor expression in the mesenteric vasculature reflect more complicated mechanisms than simple up- or down-regulation phenomena.
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Affiliation(s)
- Alberto Ricci
- Dipartimento di Scienze Cardiovascolari e Respiratorie, Università La Sapienza, Rome, Italy
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Teisman AC, Buikema H, van Veldhuisen DJ, de Zeeuw D, van Gilst WH. Direct vasodilating effects of the new dopaminergic agonist Z1046 in human arteries. J Cardiovasc Pharmacol 2000; 35:581-5. [PMID: 10774789 DOI: 10.1097/00005344-200004000-00011] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
Dopaminergic agonists remain of interest in the treatment of heart failure; however, concomitant stimulation of alpha- and beta-receptors should be avoided. This study evaluates the dopaminergic and adrenergic (vasodilating) properties of Z1046, epinine (the active metabolite of ibopamine), and dopamine. Isotonic contraction experiments were performed on human internal mammary artery rings in vitro. alpha1-Antagonistic effects of Z1046 were demonstrated by performing cumulative dose-response curves with the selective alpha1-agonist phenylephrine in the presence of Z1046. Furthermore, both alpha1- and dopamine-mediated receptor effects of Z1046, epinine, and dopamine were studied by performing cumulative dose-response relations both at baseline and in precontracted artery rings both with and without the D1-like antagonist SCH23390. In contrast to both epinine and dopamine, Z1046 is devoid of alpha1-receptor-mediated contraction. Furthermore, Z1046, epinine, and dopamine induced direct dopamine receptor-mediated vasodilation when interfering alpha1 effects were blocked. In contrast to epinine and dopamine, Z1046 is devoid of vasoconstricting properties at higher dosages. Because of its D1-like agonistic and alpha1-antagonistic properties, Z1046 is an effective vasodilator in the whole dosage range. Because of its total receptor profile, Z1046 appears to be more favorable for treatment of heart failure than is ibopamine.
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Affiliation(s)
- A C Teisman
- Department of Clinical Pharmacology, University of Groningen, The Netherlands.
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9
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Emerson M, Paul W, Page CP. Regulation of platelet function by catecholamines in the cerebral vasculature of the rabbit. Br J Pharmacol 1999; 127:1652-6. [PMID: 10455322 PMCID: PMC1566137 DOI: 10.1038/sj.bjp.0702671] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Abstract
1. 111In-labelled platelets were monitored continuously in the cerebral and pulmonary vascular beds of anaesthetized rabbits. Dopamine can, depending upon the concentration, either potentiate or inhibit thrombin-induced platelet accumulation in the cerebral vasculature of rabbits by unknown mechanisms. The effects of specific adrenergic and dopaminergic receptor antagonists were tested upon dopamine's actions on intracarotid (i.c.) thrombin-induced (80 u kg-1) platelet accumulation in the cerebral vasculature. The effect of adrenaline on the response to thrombin in this vascular bed was also investigated. 2. Thrombin-induced platelet accumulation was significantly (P<0.01) potentiated by dopamine (100 microgkg-1 min-1, i.c.) and this effect was significantly inhibited by infusion of the alpha-adrenoceptor antagonist, phentolamine. 3 A higher dose of dopamine (2 mg kg-1 min-1, i.c.) inhibited thrombin-induced platelet accumulation. The beta-adrenoceptor antagonist, propranolol, did not significantly alter this inhibitory effect whereas it was abolished by the dopamine D1 selective antagonist, SCH23390. 4 Adrenaline (when administered i.c. by bolus injection or infusion) had no significant effect on thrombin-induced accumulation at any of the doses tested. 5 Potentiation of in vivo platelet accumulation by dopamine therefore seems to occur via alpha-adrenergic receptors. However, the inhibitory effect of dopamine appears to be exerted via the activation of dopamine D1 receptors and not via beta-adrenergic receptors. Our findings confirm that dopamine, but not adrenaline, can modify platelet function in the cerebral vasculature and these observations may have implications for current and potential therapeutic uses of dopamine and selective dopaminergic compounds.
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Affiliation(s)
- Michael Emerson
- Sackler Institute of Pulmonary Pharmacology, Division of Pharmacology & Therapeutics, Guy's, King's and St. Thomas' School of Biomedical Sciences, King's College London, Manresa Road, London SW3 6LX
| | - William Paul
- Sackler Institute of Pulmonary Pharmacology, Division of Pharmacology & Therapeutics, Guy's, King's and St. Thomas' School of Biomedical Sciences, King's College London, Manresa Road, London SW3 6LX
| | - Clive P Page
- Sackler Institute of Pulmonary Pharmacology, Division of Pharmacology & Therapeutics, Guy's, King's and St. Thomas' School of Biomedical Sciences, King's College London, Manresa Road, London SW3 6LX
- Author for correspondence:
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10
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Kuchel O. Increased plasma dopamine in patients presenting with the pseudopheochromocytoma quandary: retrospective analysis of 10 years' experience. J Hypertens 1998; 16:1531-7. [PMID: 9814626 DOI: 10.1097/00004872-199816100-00019] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
OBJECTIVES A retrospective analysis was made to determine alternative diagnoses in patients with predominantly hypertensive episodes who were suspected of having pheochromocytoma but in whom this diagnosis was eliminated. DESIGN Analysis of a random university hospital population referred over a period of 10 years. METHODS Episodic clinical presentations of pheochromocytoma symptoms combined with a comparison of baseline and episodic radioenzymatically determined levels of plasma free norepinephrine and epinephrine were examined, together with prospective levels of plasma free and sulfated dopamine. RESULTS Out of 63 patients presenting with episodes of palpitations, headaches, flushing, sweating and hyperventilation (associated with hypertension in 49 patients, with hypotension in six patients and with alternating hyper- and hypotension in eight patients), 14 were diagnosed as having idiopathic hypovolemia, nine as having mastocytosis, nine as having an adrenal tumor, four as having neurogenic hypertension and one each with cocaine abuse and reninoma. Both baseline and symptomatic levels of plasma free norepinephrine and epinephrine remained within physiological limits (exceeding them moderately in baroreceptor dysfunction only), but all subgroups had a mean episodic increase over baseline in plasma dopamine sulfate (mean+/-SEM 16.7+/-5.9 to 53.2+/-19 pmol/ml; P < 0.02), unlike free dopamine. CONCLUSIONS Patients whose symptoms imitated pheochromocytoma in hemodynamic instability and frequent flushing formed a heterogeneous group, with plasma norepinephrine and epinephrine usually within physiological limits but an overall mean threefold increase in dopamine sulfate concentrations. With the various diagnoses of idiopathic hypovolemia, mastocytosis, neurogenic, secondary hypertension and cocaine abuse eliminated as a cause of pheochromocytoma-like symptoms, at least half of these patients still had unexplained, predominantly emotionally or proprioreceptive stimulation-provoked, bouts of hypertension. Sympathetic arousal dominated by an increase in dopamine sulfate without a corresponding increase in free norepinephrine, epinephrine and dopamine may be attributed to a number of neurogenic, adaptive or autocrine-paracrine dopamine release mechanisms.
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Affiliation(s)
- O Kuchel
- Clinical Research Institute of Montreal, Hôtel-Dieu Hospital, University of Montreal, Quebec, Canada
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11
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Post JB, Frishman WH. Fenoldopam: a new dopamine agonist for the treatment of hypertensive urgencies and emergencies. J Clin Pharmacol 1998; 38:2-13. [PMID: 9597553 DOI: 10.1002/j.1552-4604.1998.tb04369.x] [Citation(s) in RCA: 49] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Fenoldopam is a selective dopamine agonist that is being considered for the parenteral treatment of systemic hypertension. In both an oral and parenteral form, the drug causes peripheral vasodilation by stimulating dopamine-1 adrenergic receptors. Its pharmaco-dynamics are reviewed in this article, along with the clinical experiences in patients with hypertensive urgencies and emergencies. Intravenous fenoldopam may provide advantages over sodium nitroprusside because it can induce both a diuresis and natriuresis, is not light sensitive, and is not associated with cyanide toxicity. There is no evidence for rebound hypertension after discontinuation of fenoldopam influsion.
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Affiliation(s)
- J B Post
- Department of Medicine, Albert Einstein College of Medicine/Montefiore-Medical Center, Bronx, New York, USA
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12
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Emerson M, Paul W, Ferlenga P, Semeraro C, Page C. Effects of dopamine and selective dopamine agonists upon platelet accumulation in the cerebral and pulmonary vasculature of the rabbit. Br J Pharmacol 1997; 122:682-6. [PMID: 9375964 PMCID: PMC1564989 DOI: 10.1038/sj.bjp.0701432] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
1. A selection of novel compounds were shown to exhibit dopaminergic activity in vitro. 2. 111Indium-labelled platelets were continuously monitored in the cerebral and pulmonary vasculature of anaesthetized rabbits. The effects of dopamine and selective dopamine receptor agonists on ADP and thrombin induced platelet accumulation were recorded. 3. Pretreatment with dopamine (2 mg kg(-1) min(-1), i.v.) significantly reduced ADP (20 microg kg(-1), i.v.) induced platelet accumulation in the pulmonary vasculature whereas lower doses had no effect. 4. Dopamine (100 microg kg(-1) min(-1) intra-carotid, i.c.) potentiated thrombin (90 u kg(-1), i.c.) induced platelet accumulation in the cerebral vasculature whereas higher doses (1-2 mg kg(-1) min[-1]) inhibited accumulation. 5. The selective dopamine receptor agonists tested did not significantly inhibit platelet accumulation induced by ADP or thrombin. Two of these selective agonists, at doses higher than the intended therapeutic doses, induced thrombocytopaenia and an associated increase in platelet accumulation in the lung in response to thrombin. 6. These results extend previous in vitro studies regarding the dual actions of dopamine upon platelets and show for the first time the effects of selective dopamine receptor agonists upon platelet aggregation in vivo.
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Affiliation(s)
- M Emerson
- Sackler Institute of Pulmonary Pharmacology, King's College London
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13
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Yatsu T, Miyamoto I, Kaneko-Takanuki F, Watanabe T, Takenaka T. Pharmacological and pharmacokinetic characteristics of YM435, a novel dopamine DA1-receptor agonist, in anaesthetized dogs. J Pharm Pharmacol 1997; 49:892-6. [PMID: 9306257 DOI: 10.1111/j.2042-7158.1997.tb06131.x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Time-course of plasma concentration of unchanged drug of the dopamine DA1-receptor agonist (-)-(S)-4-(3,4-dihydroxyphenyl)-7,8-dihydroxy-1,2,3,4- tetrahydroisoquinoline hydrochloride hydrate (YM435), and its effects on blood pressure and renal blood flow were investigated in anaesthetized dogs. Continuous intravenous infusion of YM435 (0.1-3 micrograms kg-1 min-1) rapidly increased renal blood flow and lowered blood pressure in a dose-dependent manner. These effects remained generally stable throughout the infusion period. Following the start of infusion, plasma concentration of unchanged drug also rose rapidly and dose-dependently and remained virtually constant throughout the infusion period. A significant correlation was observed between log YM435 plasma concentration and the increase in renal blood flow (r = 0.93, P < 0.0001) and between the former and the reduction in blood pressure (r = 0.93, P < 0.0001). The present results indicate that YM435 produces renal vasodilatation and lowering of blood pressure in a dose-dependent manner and with rapid onset following continuous intravenous infusion, and that these effects are generally stable throughout the period of infusion. These haemodynamic effects of YM435 were in good agreement with the time-course of plasma concentration of unchanged drug.
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Affiliation(s)
- T Yatsu
- Institute for Drug Discovery Research, Yamanouchi Pharmaceutical Co. Ltd, Ibaraki, Japan.
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14
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Estan L, Martinez-Mir I, Rubio E, Morales-Olivas FJ. No evidence for dopamine-induced relaxation in isolated human mesenteric arterial strips from elderly patients. GENERAL PHARMACOLOGY 1995; 26:1687-94. [PMID: 8745157 DOI: 10.1016/0306-3623(95)00040-2] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
1. We investigate the effects of dopamine in isolated mesenteric artery from elderly patients. 2. Noradrenaline (10(-11) to 10(-4) M) and dopamine (2.7 x 10(-6) to 1.4 x 10(-3) M) induced a concentration-dependent contraction that was antagonized by prazosin. Fenoldopam (10(-8) to 10(-4) M) and clonidine (10(-9) to 10(-4) M) did not produce any contractile effects. 3. Potassium chloride (80 mM) produced a well-maintained plateau contraction and dopamine-induced contraction in these conditions, which was decreased by prazosin (10(-8) M). Neither fenoldopam nor isoprenaline (10(-10) to 10(-5) M) modified the well-maintained plateau. 4. Our results suggest that post-synaptic dopamine receptors are not present in this preparation but alpha1-adrenoceptors are present.
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Affiliation(s)
- L Estan
- Department of Pharmacology, University of Valencia, Spain
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15
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Abstract
Levosulpiride is the levorotatory enantiomer of sulpiride, a substituted benzamide indicated as an antipsychotic, antidepressant, antiemetic and antidyspeptic drug, as well as for the treatment of somatoform disorders. In vivo sulpiride displays a number of neuroleptic properties which it shares with all typical neuroleptic drugs; however, it has also a number of divergent characteristics that set it apart as the principal compound of the so-called 'atypical neuroleptic agents'. The main mechanism of action of levosulpiride consists of blocking the D2 dopaminergic receptors, preferentially located on the presynaptic membranes in the dopaminergic pathways of the brain; this means that sulpiride is a selective autoreceptor blocker. The results of series of experimental trials conducted to evaluate the toxicologic characteristics of levosulpiride are presented. Both the acute, subacute, chronic and local toxicity trials, and the studies on reproduction toxicity, mutagenic potential and oncogenic/carcinogenic potential, demonstrate that levosulpiride is well tolerated by the animals tested (rats, mice, rabbits and dogs) at doses higher than those effective in human therapy. Moreover, the findings from the experimental studies on levosulpiride lead to exclude the toxicity from accumulation, tolerance, dependence or withdrawal syndrome. In conclusion, according to the evaluated preclinical studies, levosulpiride shows pharmacotoxicologic properties which make it suitable for the management of diseases for which the drug is indicated.
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Affiliation(s)
- F Rossi
- Institute of Pharmacology and Toxicology, Faculty of Medicine and Surgery, Second University of Naples, Italy
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16
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Lorenz R, Paschke C, Born P, Clemens R. In vitro effects of the selective dopamine 1-agonist fenoldopam on the coagulation system in native whole blood: comparison to dopamine and nitroprusside. Thromb Res 1995; 77:113-8. [PMID: 7701475 DOI: 10.1016/0049-3848(95)90871-c] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Affiliation(s)
- R Lorenz
- 2nd Department of Internal Medicine, Klinikum Rechts der Isar, Technical University of Munich, Germany
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17
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Mercuro G, Rivano CA, Ruscazio M, Lai L, Manca R, Rossetti ZL, Cherchi A. Effects of 1-Year’s Therapy with the Dopamine2 Agonist Dihydroergotoxine on Blood Pressure and Plasma Noradrenaline Levels in Essential Hypertension. Clin Drug Investig 1992. [DOI: 10.1007/bf03259216] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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18
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Effects of intravenous fenoldopam (SK&F 82526-J) on blood pressure in severe hypertension. Cardiovasc Drugs Ther 1992; 6:445-6. [DOI: 10.1007/bf00054195] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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19
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MacDonald TM. Metoclopramide, domperidone and dopamine in man: actions and interactions. Eur J Clin Pharmacol 1991; 40:225-30. [PMID: 2060557 DOI: 10.1007/bf00315200] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
The effects of oral doses of the dopamine antagonist antiemetics metoclopramide and domperidone on baseline and dopamine stimulated renal function and systemic haemodynamics were assessed in a placebo controlled crossover study in 9 healthy volunteers. Metoclopramide did not change baseline ERPF, GFR or FF over 2 h post dosing but it significantly reduced baseline UNaV, UKV, urine flow, urinary dopamine excretion, supine and erect diastolic blood pressure and supine systolic blood pressure. Domperidone and placebo did not cause these effects. Metoclopramide caused a marked rise and domperidone a small fall in plasma aldosterone concentration (PAC) but placebo was without effect. Neither antiemetic altered plasma renin activity (PRA) but a small fall occurred with placebo. Two hours after pretreatment with placebo dopamine (2 micrograms/kg/min) increased effective renal plasma flow (ERPF), glomerular filtration rate (GFR), sodium excretion rate (UNaV), urine flow rate, urinary dopamine excretion rate, supine systolic blood pressure and supine and erect pulse rate and decreased the potassium excretion rate (UKV), filtration fraction (FF) and supine diastolic blood pressure. Metoclopramide pretreatment, did not attenuate the dopamine induced rise in ERPF, GFR, urine flow, urinary dopamine excretion or supine systolic blood pressure but it did attenuate the rise in pulse rate, the fall in diastolic pressure, and the antikaliuretic effect of dopamine leading to a net kaliuresis when compared to placebo. Domperidone was similar to placebo. Neither metoclopramide nor domperidone given orally caused clinically important antagonism of the renal haemodynamic effects of dopamine. However the effects of metoclopramide on blood pressure and electrolyte excretion may have clinical importance.(ABSTRACT TRUNCATED AT 250 WORDS)
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Affiliation(s)
- T M MacDonald
- Department of Clinical Pharmacology, Ninewells Hospital and Medical School, Dundee, UK
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20
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MacDonald TM, Jeffrey RF, Freestone S, Lee MR. A single dose study of the effects of fenoldopam and enalapril in mild hypertension. Eur J Clin Pharmacol 1991; 40:231-6. [PMID: 1676367 DOI: 10.1007/bf00315201] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
To clarify the contribution made by the renin-angiotensin system activation to the short lived hypotensive response to fenoldopam, the haemodynamic effects of a combination of fenoldopam (100 mg) and enalapril (5 mg) were compared with fenoldopam alone, enalapril alone and placebo in a balanced, randomised, double blind, single dose study in eight hypertensive patients. Fenoldopam caused an acute fall in blood pressure which lasted approximately 3 h after dosing and was associated with a reflex tachycardia. Enalapril caused a more gradual fall in blood pressure (onset 2 h) without a reflex tachycardia. The combination of drugs produced greater reductions in blood pressure sustained for a longer period than fenoldopam alone and with a more rapid onset than enalapril alone. In combination the hypotensive effects of fenoldopam and enalapril were clearly additive and not synergistic. Activation of the renin-angiotensin system does not antagonise significantly the hypotensive effect of fenoldopam.
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Affiliation(s)
- T M MacDonald
- Department of Clinical Pharmacology, Royal Infirmary, Edinburgh, UK
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21
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Ruffolo RR, Hieble JP, Brooks DP, Feuerstein GZ, Nichols AJ. Drug receptors and control of the cardiovascular system: recent advances. PROGRESS IN DRUG RESEARCH. FORTSCHRITTE DER ARZNEIMITTELFORSCHUNG. PROGRES DES RECHERCHES PHARMACEUTIQUES 1991; 36:117-360. [PMID: 1876708 DOI: 10.1007/978-3-0348-7136-5_4] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Affiliation(s)
- R R Ruffolo
- SmithKline Beecham Pharmaceuticals, King of Prussia, PA 19406
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22
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Aronson S, Goldberg LI, Roth S, Glock D, Moss J, Roizen MF. Preservation of renal blood flow during hypotension induced with fenoldopam in dogs. Can J Anaesth 1990; 37:380-4. [PMID: 1969772 DOI: 10.1007/bf03005596] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
The introduction of drugs that could induce hypotension with different pharmacological actions would be advantageous because side effects unique to a specific drug could be minimized by selecting appropriate therapy. Specific dopamine-1, (DA1) and dopamine-2 (DA2) receptor agonists are now under clinical investigation. Fenoldopam mesylate is a specific DA1 receptor agonist that lowers blood pressure by vasodilatation. The hypothesis that fenoldopam could be used to induce hypotension and preserve blood flow to the kidney was tested. Systemic aortic blood pressure and renal blood flow were measured continuously with a carotid arterial catheter and an electromagnetic flow probe respectively, in order to compare the cardiovascular and renal vascular effects of fenoldopam and sodium nitroprusside in ten dogs under halothane general anaesthesia. Mean arterial pressure was decreased 30 +/- 8 per cent from control with infusion of fenoldopam (3.4 +/- 2.0 micrograms.kg-1.min-1) and 34 +/- 4 per cent with infusion of sodium nitroprusside (5.9 micrograms.kg-1.min-1) (NS). Renal blood flow (RBF) increased during fenoldopam-induced hypotension 11 +/- 7 per cent and decreased 21 +/- 8 per cent during sodium nitroprusside-induced hypotension (P less than 0.01). Sodium nitroprusside is a non-selective arteriolar and venous vasodilator that can produce redistribution of blood flow away from the kidney during induced hypotension. Fenoldopam is a selective dopamine-1 (DA1) receptor agonist that causes vasodilatation to the kidney and other organs with DA1 receptors and preserves blood flow to the kidney during induced hypotension.
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Affiliation(s)
- S Aronson
- Department of Anesthesia and Critical Care, University of Chicago Hospitals, Illinois 60637
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23
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Reisin E, Huth MM, Nguyen BP, Weed SG, Gonzalez FM. Intravenous fenoldopam versus sodium nitroprusside in patients with severe hypertension. Hypertension 1990; 15:I59-62. [PMID: 1967592 DOI: 10.1161/01.hyp.15.2_suppl.i59] [Citation(s) in RCA: 32] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
In an open-label study, we compared the efficacy and safety of intravenous infusion of fenoldopam mesylate with that of sodium nitroprusside in patients with severe hypertension or in hypertensive crisis. Both antihypertensive medications were infused at a maximal dose increment of 0.2 microgram/kg/min (fenoldopam) and 1 microgram/kg/min (nitroprusside), with a maximal infusion rate of 1.5 micrograms/kg/min fenoldopam mesylate or 8 micrograms/kg/min sodium nitroprusside. Once the desired reduction in diastolic blood pressure was achieved (less than 110 mm Hg if initial diastolic blood pressure was 120-149 mm Hg, or by at least 40 mm Hg if initial diastolic blood pressure was 150-190 mm Hg), the maximal infusion rate used was maintained for at least 1 hour, and then, the infusion was slowed gradually over 2 hours. After the infusion treatment, patients remained in the hospital for 2 days of follow-up. Both antihypertensive agents successfully controlled the blood pressure in all the patients by the end of the maintenance periods. Between the baseline and the end of the maintenance period, analysis of variance showed that the changes in the variables induced by fenoldopam mesylate did not differ significantly from those induced by sodium nitroprusside. The incidence of side effects listed were similar in both groups of patients. The detection of toxic levels of thiocyanate in two patients treated with nitroprusside, however, shows that fenoldopam might be preferable for the control of a hypertensive crisis or severe hypertension in patients with decreased renal function.
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MESH Headings
- 2,3,4,5-Tetrahydro-7,8-dihydroxy-1-phenyl-1H-3-benzazepine/adverse effects
- 2,3,4,5-Tetrahydro-7,8-dihydroxy-1-phenyl-1H-3-benzazepine/analogs & derivatives
- 2,3,4,5-Tetrahydro-7,8-dihydroxy-1-phenyl-1H-3-benzazepine/therapeutic use
- Adult
- Blood Pressure/drug effects
- Blood Urea Nitrogen
- Creatine/blood
- Fenoldopam
- Ferricyanides/therapeutic use
- Heart Rate/drug effects
- Humans
- Hypertension/drug therapy
- Hypertension/metabolism
- Hypertension/physiopathology
- Injections, Intravenous
- Middle Aged
- Nitroprusside/adverse effects
- Nitroprusside/therapeutic use
- Randomized Controlled Trials as Topic
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Affiliation(s)
- E Reisin
- Nephrology Section, Louisiana State University, New Orleans
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24
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Munger MA, Benotti JR, Green JA, Jarvis RC, Nara AR, McCue JE, Pospisil RA, Kasmer RJ. Assessment of hemodynamic tolerance from a 24-hour intravenous infusion of fenoldopam mesylate in congestive heart failure. Am J Cardiol 1990; 65:206-10. [PMID: 1967511 DOI: 10.1016/0002-9149(90)90086-g] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
To determine the maintenance of pharmacodynamic effects of fenoldopam mesylate, a dopamine-1 agonist, the invasive hemodynamic profiles of 33 patients with New York Heart Association functional class III to IV congestive heart failure were examined. Fenoldopam mesylate was initiated at 0.1 micrograms/kg/min and titrated to a cardiac index greater than or equal to 25% above baseline. Upon achievement of optimal hemodynamics, maintenance infusion was begun (mean dose 0.6 micrograms/kg/min). Fenoldopam mesylate (baseline vs maximal effect) decreased systemic vascular resistance by 37% (p less than 0.001), left ventricular filling pressure by 16% (p less than 0.05) and mean arterial pressure by 11% (p less than 0.05), with an associated augmentation in cardiac index and stroke volume index by 27% (p less than 0.001). Attenuation of hemodynamic effect (maximal effect vs time) was noted in cardiac index (14% p less than 0.001), systemic vascular resistance (13% p less than 0.05) and stroke volume index (13% p less than 0.05). None of the parameters exhibited complete attenuation to baseline values. Fenoldopam mesylate improves cardiac output and lowers systemic vascular resistance with relative attenuation of pharmacodynamic effect during a 24-hour intravenous infusion.
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MESH Headings
- 2,3,4,5-Tetrahydro-7,8-dihydroxy-1-phenyl-1H-3-benzazepine/adverse effects
- 2,3,4,5-Tetrahydro-7,8-dihydroxy-1-phenyl-1H-3-benzazepine/analogs & derivatives
- 2,3,4,5-Tetrahydro-7,8-dihydroxy-1-phenyl-1H-3-benzazepine/blood
- 2,3,4,5-Tetrahydro-7,8-dihydroxy-1-phenyl-1H-3-benzazepine/therapeutic use
- Adult
- Aged
- Aged, 80 and over
- Drug Tolerance
- Female
- Fenoldopam
- Heart Failure/drug therapy
- Heart Failure/physiopathology
- Hemodynamics/drug effects
- Humans
- Infusions, Intravenous
- Male
- Middle Aged
- Time Factors
- Vasodilator Agents/adverse effects
- Vasodilator Agents/blood
- Vasodilator Agents/therapeutic use
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Affiliation(s)
- M A Munger
- Division of Cardiology, School of Medicine, Case Western Reserve University, Cleveland, Ohio
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25
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Kinter LB, Horner E, Mann WA, Weinstock J, Ruffolo RR. Characterization of the hemodynamic activities of fenoldopam and its enantiomers in the dog. Chirality 1990; 2:219-25. [PMID: 1982058 DOI: 10.1002/chir.530020405] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Fenoldopam (SK&F 82526) is a potent and selective dopamine DA-1 agonist with demonstrated renal vasodilator and antihypertensive activities in experimental animals and humans. Fenoldopam is a racemic mixture of two enantiomers, SK&F R-82526 and SK&F S-82526. The R-enantiomer is uniformly reported to be more potent than the racemate; in contrast, there is controversy regarding potency of the S-enantiomer. In these studies, the renal and systemic hemodynamic activities of fenoldopam and its enantiomers are characterized in anesthetized, phenoxybenzamine-treated dogs. The results show that the renal and systemic vasodilator activities of fenoldopam are properties of the R-enantiomer; the S-enantiomer is essentially inactive. The renal and systemic vasodilator properties of SK&F R-82526 are antagonized in a competitive fashion by the DA-1 antagonist, SK&F R-83566, but not the DA-2 antagonist, domperidone. Ganglionic blockade did not attenuate renal vasodilation associated with SK&F R-82526. Thus, the mechanism of SK&F R-82526-associated vasodilation, like that previously established for fenoldopam, is via stimulation of postganglionic DA-1 receptors.
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Affiliation(s)
- L B Kinter
- Department of Pharmacology, Smith Kline Beecham Pharmaceuticals, King of Prussia, Pennsylvania 19406-0939
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26
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Wanstall JC, O'Donnell SR. Vasodilator responses to dopamine in rat perfused mesentery are age-dependent. Br J Pharmacol 1989; 98:302-8. [PMID: 2804550 PMCID: PMC1854687 DOI: 10.1111/j.1476-5381.1989.tb16895.x] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023] Open
Abstract
1. Dose-dependent vasodilator responses to dopamine, isoprenaline, noradrenaline, 3-isobutyl-1-methylxanthine (IBMX) and sodium nitroprusside were obtained in isolated perfused mesentery preparations, taken from reserpine-treated rats of different ages. The preparations were pretreated with phenoxybenzamine (1 microM) and perfused with physiological salt solution containing cocaine (10 microM), additional KCl (20 mM) and vasopressin (0.1 microM). 2. Vasodilator responses to dopamine were abolished by the dopamine1 (DA1)-selective antagonist SCH 23390 (10 nM) and those to isoprenaline by propranolol (1 microM), but the vasodilator responses to noradrenaline were abolished only when SCH 23390 and propranolol were used together. This indicated that dopamine was acting via DA1-receptors, isoprenaline via beta-adrenoceptors and that noradrenaline could act via DA1-receptors and beta-adrenoceptors in this preparation. 3. Responses to all the vasodilator drugs decreased in magnitude between the ages of 1 and 2 months. Responses to dopamine declined further in 4 month-old rats and were negligible at 6 or 22-24 months of age. Responses to isoprenaline were well maintained up to 6 months of age, but were negligible at 22-24 months. 4. It is concluded that, in the rat mesenteric vasculature, there is a non-specific decline in responses to vasodilator drugs during development (1 to 2 months). Subsequently there is a specific decline in DA1-receptor-mediated and beta-adrenoceptor-mediated responses; the former are lost at an earlier age than the latter. This different time course suggests that age influences receptor numbers, or their coupling to adenylate cyclase, rather than a post-receptor event in the adenylate cyclase/cyclic AMP pathway.
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Affiliation(s)
- J C Wanstall
- Department of Physiology and Pharmacology, University of Queensland, St Lucia, Australia
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27
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Kerns WD, Arena E, Morgan DG. Role of dopaminergic and adrenergic receptors in the pathogenesis of arterial lesions induced by fenoldopam mesylate and dopamine in the rat. THE AMERICAN JOURNAL OF PATHOLOGY 1989; 135:339-49. [PMID: 2571297 PMCID: PMC1879911] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Fenoldopam mesylate (FM), a selective, postjunctional, dopaminergic (DA1) vasodilator, causes a novel lesion of large caliber splanchnic arteries (100 to 800 microns) in the rat characterized by necrosis of medial smooth muscle cells and hemorrhage. FM does not induce lesions in other vascular beds of the rat or in dogs or monkeys. Dopamine, like FM, causes hemorrhagic lesions of large caliber splanchnic arteries in the rat, as well as fibrinoid necrosis of small caliber arteries (less than 100 microns) of the splanchnic, cerebral, coronary, and renal vascular beds. Dopamine, an alpha- and beta-adrenoceptor and dopaminergic agonist, is used clinically, principally as a pressor agent. Because these arterial lesions were believed to result from the pharmacologic activity of these two compounds, the role of vascular receptor subtypes in their pathogenesis was investigated. Rats were coexposed to either FM or dopamine and a variety of receptor antagonists (alpha, beta, DA1, DA2, and 5HT2). In rats coexposed to the alpha-adrenoreceptor antagonist phenoxybenzamine (PBZ) and either FM or dopamine, the incidence and severity of hemorrhagic lesions of large caliber arteries were increased; PBZ, however, prevented the formation of dopamine-induced fibrinoid lesions in arteries of small caliber. SK&F 83566-C, a selective DA1 dopaminergic receptor antagonist, prevented the induction of FM and dopamine-induced hemorrhagic lesions of large caliber arteries. Rats exposed concurrently to dopamine, phenoxybenzamine, and SK&F 83566-C were free of all arterial lesions. The other receptor antagonists tested did not prevent arterial injury. Thus, the induction of splanchnic arterial lesions in the rat by dopamine and FM is caused by stimulation of, and interaction between, alpha-adrenoceptors and dopaminergic DA1 receptors. Activation of the postjunctional, dopaminergic (DA1) receptor is causally associated with the induction of novel hemorrhagic lesions of large caliber splanchnic arteries in the rat.
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Affiliation(s)
- W D Kerns
- Department of Experimental Pathology, Smith Kline and French Laboratories, King of Prussia, Pennsylvania 19406
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28
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Bednarczyk EM, White WB, Munger MA, Gonzalez FM, Panacek EA, Weed SG, Rutherford WF, Nara AR, Green JA. Comparative acute blood pressure reduction from intravenous fenoldopam mesylate versus sodium nitroprusside in severe systemic hypertension. Am J Cardiol 1989; 63:993-6. [PMID: 2564726 DOI: 10.1016/0002-9149(89)90157-4] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Affiliation(s)
- E M Bednarczyk
- Division of Cardiology, University Hospitals of Cleveland, Ohio 44106
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29
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Young JB, Leon CA, Pratt CM, Kingry C, Taylor AA, Roberts R. Intravenous fenoldopam in heart failure: comparing the hemodynamic effects of dopamine1 receptor agonism with nitroprusside. Am Heart J 1988; 115:378-84. [PMID: 2893527 DOI: 10.1016/0002-8703(88)90485-1] [Citation(s) in RCA: 33] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
Dopamine1 receptors mediate hemodynamic effects that may be beneficial in patients with congestive heart failure. We infused the selective dopamine1 receptor agonist, fenoldopam mesylate (SKF 82526 J), to evaluate hemodynamic and neurohumoral changes during continuous intravenous infusion in patients with congestive heart failure and compared them with the effects of nitroprusside, a traditional vasodilator that works by a distinctly different mechanism. In 15 patients with a mean radionuclide ejection fraction of 17%, the agents were infused in a random-ordered, double-blinded, crossover, active drug-controlled protocol after optimal dosing was determined during a titration period. Hemodynamic changes were induced in minutes with both drugs during a mean (+/- standard deviation) infusion dose of 1.45 +/- 1.66 micrograms/kg/min for fenoldopam and 2.99 +/- 1.59 micrograms/kg/min for nitroprusside. At 1 hour, mean blood pressure decreased and cardiac index rose with both drugs, and the effect lasted throughout the 6-hour infusion period. Nitroprusside, but not fenoldopam, reduced right heart filling pressures (including mean pulmonary capillary wedge, mean right atrial, and mean pulmonary artery pressures) during the infusion period. Both drugs caused significant reduction in systemic vascular and pulmonary arteriolar resistances. No significant change occurred in plasma norepinephrine levels. Fenoldopam ameliorates some of the adverse hemodynamic changes that occur during heart failure but does not reduce right heart filling pressures as does nitroprusside. Because of fenoldopam's unique characteristics, it may benefit certain patients with heart failure.
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Affiliation(s)
- J B Young
- Section of Cardiology, Methodist Hospital, Houston, TX
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Weber RR, McCoy CE, Ziemniak JA, Frederickson ED, Goldberg LI, Murphy MB. Pharmacokinetic and pharmacodynamic properties of intravenous fenoldopam, a dopamine1-receptor agonist, in hypertensive patients. Br J Clin Pharmacol 1988; 25:17-21. [PMID: 2897206 PMCID: PMC1386609 DOI: 10.1111/j.1365-2125.1988.tb03276.x] [Citation(s) in RCA: 53] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023] Open
Abstract
1 The pharmacokinetic properties of intravenous fenoldopam, a selective dopamine1-receptor agonist, were studied in 10 patients with essential hypertension. 2 Reduction in blood pressure was linearly related to the log fenoldopam plasma concentration (r = 0.69) and the log fenoldopam infusion rate (r = 0.71). 3 The mean elimination half-life (+/- s. e. mean) was 9.8 +/- 1.0 min. The total body clearance was 30.3 +/- 2.3 ml kg-1 min-1 and the volume of distribution was 582 +/- 62 ml kg-1. 4 The rapid onset of action, short elimination half-life, linear dose-response relationship, and ease of administration suggest that fenoldopam may have a role where parenteral treatment of hypertension is required.
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Affiliation(s)
- R R Weber
- Department of Pharmacological and Physiological Science, University of Chicago, Illinois 60637
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31
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Murphy MB, McCoy CE, Weber RR, Frederickson ED, Douglas FL, Goldberg LI. Augmentation of renal blood flow and sodium excretion in hypertensive patients during blood pressure reduction by intravenous administration of the dopamine1 agonist fenoldopam. Circulation 1987; 76:1312-8. [PMID: 2890447 DOI: 10.1161/01.cir.76.6.1312] [Citation(s) in RCA: 91] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
Activation of dopamine1 (DA1) receptors relaxes vascular smooth muscle, especially in the renal vascular bed. Fenoldopam, the first selective DA1-receptor agonist that can be administered to man, was infused intravenously in 17 patients with essential hypertension (mean blood pressure 152/101 mm Hg). It reduced blood pressure in a dose-dependent fashion at doses between 0.025 and 0.5 microgram/kg/min and the antihypertensive effect was sustained during 2 hr infusions. In 10 patients studied during free-water diuresis, fenoldopam increased renal plasma flow by 42%, glomerular filtration rate by 6%, and sodium excretion by 202%, while lowering mean arterial pressure by 12% (all p less than .05). Similar promotion of sodium excretion was observed during blood pressure reduction in six additional patients studied without water loading. Pronounced enhancement of renal function in spite of blood pressure reduction suggests that fenoldopam might have a special role in the treatment of patients with hypertension and renal impairment.
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Affiliation(s)
- M B Murphy
- Department of Pharmacological and Physiological Sciences, University of Chicago, IL 60637
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