None of the receptor ligands studied: the dopamine D2 antagonist eticlopride, D2/D3 antagonist haloperidol, alpha1-adrenergic antagonist prazosin, N-methyl-D-aspartate antagonist MK-801, 5-HT2/D2 antagonist mianserin, D2/D3 agonist quinpirole and alpha2-adrenergic agonist clonidine co-administrated with repeated amphetamine (AMPH) injections blocked the AMPH-induced decrease in the striatal and...

A number of studies have recently suggested that the D3 receptor [ 11 is located presynaptically and functions as an autoreceptor [2-41. These studies have demonstrated that 7-hydroxy-di-npropyl-2-aminotetralin [ ( + )-7-OH-DPAT], a ligand with significant D3 receptor affinity, decreases dopamine release in limbic and striatal regions. However, the selectivity of (+)-7-OHDPAT for the D3 recepto...

We have isolated and characterized a monoglucuronide fraction of 9,10-secocholesta-5,7,10(19)triene-1 alpha, 3 beta, 25-triol, 5,6-cis isomer (1,25-dihydroxyvitamin D3) from rat bile. Polar radioactive metabolites of 1,25-dihydroxyvitamin D3 were purified by a sequence of chromatographic procedures which utilized Amberlite XAD-2, diethylaminohydroxypropyl Sephadex LH-20, liquid-liquid partition...

1 The D3 dopamine receptor presumably activates Gi/Go subtypes of G-proteins, like the structurally analogous D2 receptor, but its signalling targets have not been clearly established due to weak functional signals from cloned receptors as heterologously expressed in mostly non-neuronal cell lines. 2 In this study, recombinant human D3 receptors expressed in a human neuroblastoma cell line, SH-...

Deletion of C19 in the structure of 1 alpha,25-dihydroxyvitamin D3 [1,25(OH)2D3] does not substantially alter the biological potency but prevents the conversion between the vitamin and the previtamin form. Hence, this modification allows the study of locked previtamin and vitamin forms. The locked 19-nor-1,25(OH)2-previtamin D3 analog (19-nor-previtamin D) had a low biological activity and was ...

The functional role of the exon 3 growth hormone receptor (d3GHR) polymorphism in human and its distributions in different populations is not clearly understood. The presence of full length growth hormone (flGHR) is the most important in metabolic risk factors. The aim of this study was to define the frequency distribution of d3GHR/full-length GHR in an Iranian population. The presence of the d...

Cortical gamma oscillations are associated with cognitive processes and are altered in several neuropsychiatric conditions such as schizophrenia and Alzheimer's disease. Since dopamine D3 receptors are possible targets in treatment of these conditions, it is of great importance to understand their role in modulation of gamma oscillations. The effect of D3 receptors on gamma oscillations and the...

Here, we show that the platelet-derived growth factor receptor (PDGFR) regulates myeloid and monocytic differentiation of HL-60 myeloblastic leukemia cells in response to retinoic acid (RA) and vitamin D3 (D3), respectively. Both RA and D3 decreased the expression of PDGFR-alpha and PDGFR-beta throughout differentiation. When cells were treated with the PDGFR inhibitor AG1296 in addition to RA ...

Background: We investigated serum levels of 25-hydroxyvitamin D3 and the vitamin D receptor (VDR) gene polymorphisms (Fokl, Bsml) in Egyptian patients with Behçet’s disease (BD) and their relationship to disease manifestations and activity. Methods: We studied 45 patients with BD fulfilling the international study group criteria ISG for BD (1999) and 45 healthy, matched controls. We evaluated V...

objective(s) deregulation of the immune system through allied factors and cytokine responses are thought to be important contributors to the pathogenesis of asthma. vitamin d3 and its nuclear receptor appear to be factors that maybe involved in regulating immune responses during the progression of asthma. the aim of this study was to investigate the association between polymorphisms in intron 8...