Dopamine D3 receptors are preferentially localized in the limbic system and midbrain, and thus may be involved in the pathophysiology of neuropsychiatry disorders. [11C](+)-PHNO is the first preferential D3 receptor radioligand in humans, yet there are no blockade studies with a D3 receptor antagonist in humans. This study characterized the blockade of [11C](+)-PHNO binding by ABT-925, a D3 rec...

The aim of the present study was to determine the respective role of 1,25-dihydroxyvitamin D3 on vaginal epithelium and 1,25-dihydroxyvitamin D3 receptor expression in ovariectomized rats and vitamin D3 treated rats. Bilateral ovariectomies were performed in 20 mature, non-pregnant Wistar female rats. All the animals were divided into 2 groups consisting of 10 rats each. Group I served as contr...

Background: Several lines of evidence suggest that oxidized LDL (Ox-LDL) scavenger receptors play a crucial role in the genesis and progression of diabetic atherosclerosis. This study aimed to elucidate the effect of vitamin D3 on gene expression of lectin-like oxidized LDL receptor-1 (LOX-1), scavenger receptor-A (SR-A), Cluster of Differentiation 36 (CD36), and Cluster of Differentiation 68 (...

1,25-Dihydroxyvitamin D3 is believed to mediate the regulation of calcium metabolism by a steroid hormone receptor mechanism. We now demonstrate that phosphorylation of the 1,25-dihydroxyvitamin D3 receptor occurs rapidly in embryonic chick duodenal organ culture in response to 1,25-dihydroxyvitamin D3. Phosphorylation of the receptor is strongly induced within 1 h by 1,25-dihydroxyvitamin D3 a...

The dopamine D3 receptor is expressed primarily in regions of the brain that are thought to influence motivation and motor functions. To specify in vivo D3 receptor function, we generated mutant mice lacking this receptor. Our analysis indicates that in a novel environment, D3 mutant mice are transiently more active than wild-type mice, an effect not associated with anxiety state. Moreover, D3 ...

The D3 dopamine receptor is postulated to play an important role in the regulation of neurotransmitter secretion at both pre- and postsynaptic terminals. However, this hypothesis and the underlying mechanisms remain untested because of the lack of D3-selective ligands, paucity of appropriate model secretory systems, and the weak and inconsistent coupling of D3 receptors to classical signal tran...

Endochondral ossification comprises a cascade of cell differentiation culminating in chondrocyte hypertrophy and is negatively controlled by soluble environmental mediators at several checkpoints. Proteinases modulate this control by processing protein signals and/or their receptors. Here, we show that insulin-like growth factor I can trigger hypertrophic development by stimulating production a...

the functional role of the exon 3 growth hormone receptor ( d3 ghr) polymorphism in human and its distributions in different populations is not clearly understood. the presence of full length growth hormone ( fl ghr) is the most  important in metabolic risk factors. the aim of this study was to define the frequency distribution of d3 ghr/full-length ghr in an iranian population. the presence of...

The dopamine D3 receptor subtype was identified in rat kidney using both light microscopic immunohistochemistry and electron microscopic immunocytochemistry. Antipeptide polyclonal antisera were directed to both extracellular and intracellular regions of the native D3 receptor. Selectivity of the antipeptide antisera was validated by their ability to recognize native receptor protein expressed ...

The dopamine D3 receptor, which is highly enriched in nucleus accumbens (NAc), has been suggested to play an important role in reinforcement and reward. To understand the potential cellular mechanism underlying D3 receptor functions, we examined the effect of D3 receptor activation on GABAA receptor (GABAAR)-mediated current and inhibitory synaptic transmission in medium spiny neurons of NAc. A...