Search results for "dopamine agonist"
showing 8 items of 48 documents
Identification and Quantification of Dopamine Receptor 2 in Human Eutopic and Ectopic Endometrium: A Novel Molecular Target for Endometriosis Therapy1
2010
Previous studies in an experimental mouse model of endometriosis have shown that the dopamine agonist (DA) cabergoline (Cb2) reduces angiogenesis and endometriotic lesions, hypothetically binding to the dopamine receptor type-2 (DRD2). To date, this has not been described in human endometrium and/or endometriotic lesions. Thus, we aimed to investigate the presence of DRD2 in said tissues. Endometrium fragments were implanted in nude mice treated with different doses of Cb2. Polymerase chain reaction assays and immunohistochemistry were performed to analyze the gene and protein expressions (respectively) of DRD2, VEGF, and VEGF receptor-2 (KDR). In addition, lesions and endometrium from wome…
Practical importance of neuroprotection in Parkinson's disease.
2003
Consensus could be reached that there is overwhelming evidence of preclinical neuroprotection. However, the evidence of neuroprotection/neurorescue under clinical conditions is limited. Lessons from clinical trials designed to show neuroprotection (selegiline, amantadine, dopamine agonists) demonstrate that with the drugs available neuroprotection/neurorescue has to start as early as possible. A PET-controlled clinical trial with ropinirole shows that there seems to be a good chance for neuroprotection in the early phase of Parkinson's disease in patients treated from the very beginning of the disease while there is no such benefit in patients with a late start of a neuroprotective therapeu…
Effects of dopamine in isolated rat colon strips.
2005
The aim of the present work is to investigate the effects of dopamine on isolated rat colon strips, and whether dopamine receptors are involved in these effects. Experiments on spontaneous motility and under potassium contraction were performed with dopamine and isoprenaline, both in the absence and presence of antagonists (distal colon strips, isotonic recording, Tyrode solution, 31 °C, 1 g of resting tension). At higher concentration (10–4mol/L), dopamine abolished spontaneous motility of the rat colon and this effect was not modified by antagonists. In isolated rat colon strips that were depolarized with potassium, dopamine produced concentration-dependent relaxation, without significant…
Impact of serotonin 2C receptor null mutation on physiology and behavior associated with nigrostriatal dopamine pathway function.
2009
The impact of serotonergic neurotransmission on brain dopaminergic pathways has substantial relevance to many neuropsychiatric disorders. A particularly prominent role has been ascribed to the inhibitory effects of serotonin 2C receptor (5-HT2CR) activation on physiology and behavior mediated by the mesolimbic dopaminergic pathway, particularly in the terminal region of the nucleus accumbens. The influence of this receptor subtype on functions mediated by the nigrostriatal dopaminergic pathway is less clear. Here we report that a null mutation eliminating expression of 5-HT2CRs produces marked alterations in the activity and functional output of this pathway. 5-HT2CR mutant mice displayed i…
Response to dopamine agonists of the rat isolated uterus.
1993
1. Quinpirole did not produce any effect in isolated uterus from oestrogenized rats even when it is contracted by KCl (37 mM). 2. Fenoldopam produced a relaxant effect on rat isolated uterus contracted by KCl which was not significantly modified by SCH 23390. 3. Reserpine decreased the effect of the lowest doses of fenoldopam. In reserpinized rats, propranolol (10(-9), 10(-8), 10(-7) M) antagonized the effect of the lowest doses of fenoldopam and neither SCH 23390, sulpiride nor ranitidine modified the effect of fenoldopam. 4. The results confirm our previous finding that DA1-receptors are not functional in our preparation. The effect of fenoldopam was partially due to a catecholamine-relea…
Dopamine agonists in schizophrenia: a review.
1995
Although it is unlikely that the different types of course and severity of schizophrenia are caused by one neurochemical abnormality alone, indirect pharmacological evidence still suggests a relative excess of dopaminergic activity being implicated in the pathogenesis of most of the schizophrenic symptoms, e.g. positive symptomatology. Synthesis and release of dopamine as well as firing rates of dopaminergic neurons are controlled by stimulation of autoreceptors via a negative feedback regulation. Investigations on therapeutic effects of autoreceptor-nonselective dopamine agonists in schizophrenia have yielded inconsistent results. Dopamine autoreceptor agonists like pramipexole, roxindole,…
Prevention of OHSS: Current strategies and new insights
2010
Abstract Ovarian hyperstimulation syndrome (OHSS) is an iatrogenic and potentially life threatening condition that affects young healthy patients. Many strategies have been proposed to prevent this syndrome. However, to avoid OHSS without compromising on IVF outcome is still a challenge. The most important action is to identify patients at risk even before ovarian stimulation is initiated and to give them special attention. Coasting is the most popular method to avoid/minimize OHSS. Cycle cancellation, cryopreservation, GnRH antagonists, GnRH agonists, i.v. albumin are other strategies that can provide some kind of benefit but do not completely avoid both early and late forms of OHSS and/or…
The Effects of Epinine on Arterial Blood Pressure and Regional Vascular Resistances in Anesthetized Rats
1998
1. We carried out experiments in anesthetized rats to study the hemodynamic effects of intravenous injections of epinine. 2. Epinine (1-320 micrograms/kg) produced a biphasic effect on mean arterial blood pressure (n = 30). At doses lower than 40 micrograms/kg, arterial blood pressure decreased (by as much as 21.5 +/- 3.4%), though at higher doses it increased dose dependently (by as much as 73.2 +/- 14.5%). Epinine also produced bradicardia in a dose-dependent manner (by as much as 26.4 +/- 4.9%). Sulpiride (100 micrograms/kg) suppressed the hypotensive effect of epinine but did not change the hypertensive effect. In the presence of prazosin (1,000 micrograms/kg), arterial blood pressure r…