Dopamine D1-like and D2-like receptors are expressed in the pulmonary arteries, however there is a little information about their effect on vascular tone in pulmonary circulation, even the vascular effect of activation of the dopamine D and D subtypes in physiological and pathological conditions such as pulmonary hypertension is unknown. The objective of this study was to evaluate the vascular response of trunk pulmonary artery rings from saline and monocrotaline-treated rats in the presence of selective dopamine receptor agonists. In trunk pulmonary artery rings with intact and denuded endothelium, cumulative concentration-response curves were performed for phenylephrine, acetylcholine, and dopamine receptor agonists (apomorphine-D2-like, SKF38393-D, quinpirole-D/D, 7-OH-DPATD, and PD168077-D) alone and in the presence of corresponding selective dopamine receptor antagonists (SCH23390-D, raclopride-D/D, U99194 maleate-D, and L-745,870-D). Contractile and relaxant effects generated during the activation with phenylephrine and acetylcholine, respectively, were significantly reduced in intact and denuded endothelium trunk pulmonary artery rings from monocrotaline rats in comparison with control rats. All dopamine receptor agonists, except the 7-OH-DPAT, produced significant vascular relaxation in intact trunk pulmonary artery rings precontracted with phenylephrine in both experimental groups. Also, the vascular relaxation of SKF38393, and particularly apomorphine and PD168077 was significant in denuded endothelium trunk pulmonary artery rings from control and monocrotaline groups. Furthermore, the vasorelaxation induced by these dopamine agonists was significantly reduced in pulmonary preparations from monocrotaline-treated rats in comparison to that recorded in preparations from control rats. The effect of dopamine receptor agonists decreased significantly in the presence of the corresponding antagonist in both experimental groups. The results support that dopamine D receptor agonist induces significant vascular relaxation, whereas dopamine D receptor agonist induces vasoconstriction in intact and denuded endothelium trunk pulmonary artery rings in control and monocrotaline-induced pulmonary arterial hypertension rats.
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http://dx.doi.org/10.26402/jpp.2022.3.15 | DOI Listing |
Angew Chem Int Ed Engl
January 2025
University of Strasbourg, UMR 7213 CNRS, 74, Route du Rhin, 67401, Illkirch-Strasbourg, FRANCE.
Molecular recognition and detection of small bioactive molecules, like neurotransmitters, remain a challenge for chemists, whereas nature found an elegant solution in form of protein receptors. Here, we introduce a concept of a dynamic artificial receptor that synergically combines molecular recognition with dynamic imine bond formation inside a lipid nanoreactor, inducing a fluorescence response. The designed supramolecular system combines a lipophilic recognition ligand derived from a boronic acid, a fluorescent aldehyde based on push-pull styryl pyridine and a phenol-based catalyst.
View Article and Find Full Text PDFClin Neuropharmacol
January 2025
MedStar Georgetown University Hospital, Washington, DC.
Introduction: Adjunctive therapies to treat OFF episodes resulting from long-term levodopa treatment in Parkinson disease (PD) are hampered by safety and tolerability issues. Istradefylline offers an alternative mechanism (adenosine A2A receptor antagonist) and therefore potentially improved tolerability.
Methods: A systematic review of PD adjuncts published in 2011 was updated to include randomized controlled trials published from January 1, 2010-April 15, 2019.
J Neurochem
January 2025
Department of Pathology, School of Veterinary Medicine, University of São Paulo, Sao Paulo, Brazil.
Autism spectrum disorder (ASD) is a complex developmental disorder characterized by several behavioral impairments, especially in socialization, communication, and the occurrence of stereotyped behaviors. In rats, prenatal exposure to valproic acid (VPA) induces autistic-like behaviors. Previous studies by our group have suggested that the autistic-like phenotype is possibly related to dopaminergic system modulation because tyrosine hydroxylase (TH) expression was affected.
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View Article and Find Full Text PDFPharmacol Biochem Behav
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In vivo Electrophysiology Research Group, Department of Physiology and Neurobiology, Eötvös Loránd University, Hungary. Electronic address:
Dopaminergic system gains importance in homeostatic sleep regulation, but the role of different dopamine receptors is not well-defined. 72 h rat electrocorticogram and sleep recordings were made after single application of dopaminergic drugs in clinical use or at least underwent clinical trials. The non-selective agonist apomorphine evoked short pharmacological sleep deprivation with intense wakefulness followed by pronounced sleep rebound.
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