Search results for "Dopamine"

Electrocatalysis of neurotransmitter catecholamines by 2,4,6-triphenylpyrylium ion immobilized inside zeolite Y supercages

1999

2,4,6-Triphenylpyrylium ions entrapped inside the supercages of Y zeolite exert a remarkable catalytic effect toward the electrochemical oxidation of dopamine and norepinephrine (neurotrasmitter catecholamines) in neutral aqueous media. Domenech Carbo, Antonio, Antonio.Domenech@uv.es

Targeting the vascular endothelial growth factor system to prevent ovarian hyperstimulation syndrome

2008

BACKGROUND: Ovarian hyperstimulation syndrome (OHSS) typically occurs when ovaries are primed with FSH/ LH and subsequently exposed to hCG. The ultimate pathophysiological step underlying this clinical picture is increased vascular permeability (VP). METHODS: A search of the literature was carried out using PubMed and the authors’ files. RESULTS: In rodents and humans, the expression of vascular endothelial growth factor (VEGF) and VEGF receptor 2 (VEGFR-2) mRNA increases during ovarian stimulation. With the administration of hCG, the expression of each rises to a maximum. Expression of VEGF/VEGFR-2 mRNAs correlates with enhanced VP, with both peaking 48 h following an injection of hCG. Imm…

In vitro synthesis of dopamine and noradrenaline in the isolated rat pineal gland: day-night variations and effects of electrical stimulation.

1989

: Isolated rat pineal glands were incubated in vitro in a medium containing [I4C]dopamine or [14C]tyrosine, and the tissue contents of l4C-labelled and total dopamine and noradrenaline were determined by HPLC followed by electrochemical detection and scintillation spectrometry. During incubation with [l4C]dopamine, the labelled amine accumulated in pineal glands and was partially converted into [l4C]noradrenaline. Nomifensine, a neuronal amine uptake blocker, largely inhibited the accumulation of [l4C]dopamine and the formation of [14C]noradrenaline. These experiments demonstrated dopamine β-hydroxylase activity in the sympathetic nerves of the pineal gland. During incubation with [14C]tyro…

Pituitary resistance to thyroid hormone action with preserved circadian rhythm of thyrotropin in a postmenopausal woman.

1992

We assessed the 24-h behavior of circulating TSH and the dopaminergic control on TSH release in a postmenopausal woman, who had elevated levels of serum thyroid hormones and an inappropriately high concentration of serum TSH, indicating pituitary resistance to thyroid hormone action. The patient was found to have a daily profile of serum TSH similar to that of normal subjects, except for the persistently elevated 24 h levels, suggesting that alterations in thyroid hormone negative feedback control did not affect substantially circadian TSH rhythm. The acute administration of a dopamine antagonist drug (metoclopramide) resulted in a markedly elevated peak of serum TSH, similar both in the mo…

A Reassessment of the Therapeutic Potential of a Dopamine Receptor 2 Agonist (D2-AG) in Endometriosis by Comparison against a Standardized Antiangiog…

2021

Dopamine receptor 2 agonists (D2-ags) have been shown to reduce the size of tumors by targeting aberrant angiogenesis in pathological tissue. Because of this, the use of a D2-ag was inferred for endometriosis treatment. When assayed in mouse models however, D2-ags have been shown to cause a shift of the immature vessels towards a more mature phenotype but not a significant reduction in the amount of vascularization and size of lesions. These has raised concerns on whether the antiangiogenic effects of these compounds confer a therapeutic value for endometriosis. In the belief that antiangiogenic effects of D2-ags in endometriosis were masked due to non-optimal timing of pharmacological inte…

Evaluación estandarizada del potencial antiangiógénico del agonista dopaminérgico en el tratamiento de la endometriosis

2018

La endometriosis es una enfermedad crónica, de elevada prevalencia y etiopatogenia no claramente establecida, para la que no se dispone, actualmente, de un tratamiento seguro y eficaz a largo plazo. El establecimiento de la angiogénesis como uno de los requisitos fundamentales en la implantación y desarrollo de la enfermedad ha llevado a considerar los fármacos antiangiogénicos como una potencial diana terapéutica. Estos compuestos han demostrado, en modelos animales, reducir el tamaño de las lesiones endometriales; sin embargo, el uso de estos compuestos en humanos se ve limitado por el intolerable perfil de efectos secundarios que presenta. Los agonistas dopaminérgicos (fármacos con un pe…

DEFECTS IN DOPAMINERGIC PATHWAY AFFECT CONTRACTILITY OF COLON FROM HYPOXANTHINE-GUANINE PHOSPHORIBOSYLTRANSFERASE (HPRT) KNOCKOUT MICE.

2010

Lesch-Nyhan disease is an X-linked neurobehavioral and metabolic disorder caused by lack of hypoxanthine phosphoribosyltransferase (HPRT), a housekeeping enzyme responsible for recycling purines. The mechanisms underlying the neuropathology are not well understood, but the main neurochemical defect, in central nervous system, is linked to a dysfunction of dopaminergic pathway. In the enteric nervous system the dopaminergic nerves are a subset neurons of regulating gut motility, thus we investigated possible changes in colonic motility of HPRT ¯mice related to the dopaminergic control. We evaluated, in vitro, the mechanical activity of circular muscle strips from wild type and HPRT – mouse c…

Bidirectional cell-matrix interaction dictates neuronal network formation in a brain-mimetic 3D scaffold

2022

Human pluripotent stem cells (hPSC) derived neurons are emerging as a powerful tool for studying neurobiology, disease pathology, and modeling. Due to the lack of platforms available for housing and growing hPSC-derived neurons, a pressing need exists to tailor a brain-mimetic 3D scaffold that recapitulates tissue composition and favourably regulates neuronal network formation. Despite the progress in engineering biomimetic scaffolds, an ideal brain-mimetic scaffold is still elusive. We bioengineered a physiologically relevant 3D scaffold by integrating brain-like extracellular matrix (ECM) components and chemical cues. Culturing hPSCs-neurons in hyaluronic acid (HA) gels and HA-chondroitin…

DA-Phen, a new dopamine aminoacid conjugate: in vivo testing and molecular modeling as dopaminergic modulator

2014

Structure-activity relationship of dopaminergic halogenated 1-benzyl-tetrahydroisoquinoline derivatives

2009

Two series of halogenated 1-benzyl-7-chloro-6-hydroxy-tetrahydroisoquinolines were prepared to explore the influence of each series on the affinity for dopamine receptors. All the compounds displayed a high affinity for D(1)-like and/or D(2)-like dopamine receptors in striatal membranes, although they were unable to inhibit [(3)H]-dopamine uptake in striatal synaptosomes. The halogen placed on the benzylic ring in 1-benzyl-THIQs, compounds of the series 1, 2'-bromobenzyl derivatives with K(i) values into the nanomolar range, and the series 2, 2',4'-dichlorobenzyl-THIQ homologues, proves to be an important factor to modulate affinity at dopamine receptor. (C) 2009 Elsevier Masson SAS. All ri…