Memories of learned associations between the rewarding properties of drugs and environmental cues contribute significantly to craving and relapse in humans. We have investigated how dopamine (DA) D1 and D3 receptors modulate the acquisition and extinction of cocaine-induced reward learning and associated changes in cellular signaling in reward circuits in the brain. We found that D1 receptor mu...

Dopamine and angiotensin II negatively interact to regulate sodium excretion and blood pressure. D3 dopamine receptors downregulate angiotensin type 1 (AT1) receptors in renal proximal tubule cells from normotensive Wistar-Kyoto rats. We determined whether AT1 receptors regulate D3 receptors and whether the regulation is different in cultured renal proximal tubule cells from normotensive and sp...

Human trophoblastic cells (T3M-3) metabolized 25-hydroxyvitamin D3 into two more polar metabolites during in vitro incubations. A two-step high pressure liquid chromatography system revealed two unique elution positions of those trophoblastic cell-derived metabolites that exactly co-migrated with the elution positions of 5(Z)-19-nor-10-oxo-25-hydroxyvitamin D3 and 5(E)-19-nor-10-oxo-25-hydroxyv...

BACKGROUND Diarylheptanoid (D3) isolated from the medicinal plant, Curcuma comosa, has estrogenic activity. OBJECTIVE We aimed to elucidate the mechanism(s) of D3 action and compare it with that of 17β-estradiol (E2) using both in vitro and in vivo uterine models. METHODS We used human uterine (Ishikawa) cells to determine the estrogenic action of D3 on the activation and nuclear translocat...

The neuromodulator dopamine plays an important role in synaptic plasticity. The effects depend on receptor subtypes, affinity, concentration level, and the kind of neuroplasticity induced. In animal experiments, dopamine D2-like receptor stimulation revealed partially antagonistic effects on plasticity, which might be explained by dosage dependency. In humans, D2 receptor block abolishes plasti...

In search of a cell line in which the D3 dopamine receptor is expressed endogenously, we found that the neuron-derived human medulloblastoma cell line TE671 expresses the human D3 (hD3) and D1 (hD1) receptor, but neither the D2 or D4 receptors. Exposure of TE671 cells to the D3 agonist 7-OH-DPAT (DPAT), or to the D1 agonist SKF-38393 (SKF) increased the expression of hD3 or hD1 mRNA, respective...

Repeated exposure to cocaine can induce persistent alterations in the brain. The structural remodeling of dendrites and dendritic spines is thought to play a critical role in cocaine addiction. We previously demonstrated that signaling via dopamine D1 and D3 receptors have opposite effects on cocaine-induced gene expression. Here, we show that cocaine-induced structural remodeling in the nucleu...

The transient receptor potential cation channel C6 (TRPC6) is a slit diaphragm protein expressed by podocytes. TRPC6 gain-of-function mutations cause autosomal dominant focal segmental glomerulosclerosis. In acquired proteinuric renal disease, glomerular TRPC6 expression is increased. We previously demonstrated that acquired increased TRPC6 expression is ameliorated by antiproteinuric angiotens...

Aging is associated with a decrease in motor function and a concomitant increase in muscle stiffness and tone. The striatum plays a critical role in the control of motor function, and it receives strong dopamine (DA) innervation from the substantia nigra. DA actions are mediated by both excitatory D1-like (D1 and D5) and inhibitory D2-like (D2, D3, and D4) receptors, and D1, D2, and D3 receptor...

The vitamin D receptor (VDR) serves as a for active hydroxyderivatives. formation of hydroxyderivatives requires the presence specific cytochrome P450 (CYP) enzymes metabolism. These can be further hydroxylated by CYP27B1 at C1α-position which increases their affinity VDR. However, role in antiproliferative and antifibrotic activities CYP11A1-derived D3-metabolites is unknown. We tested action ...