We have investigated the heterodimerization of ORL1 receptors and classical members of the opioid receptor family. All three classes of opioid receptors could be co-immunoprecipitated with ORL1 receptors from both transfected tsA-201 cell lysate and rat dorsal root ganglia lysate, suggesting that these receptors can form heterodimers. Consistent with this hypothesis, in cells expressing either ...

Glioblastoma are the most frequent and malignant human brain tumors, having a very poor prognosis. The enhanced radio- and chemoresistance of glioblastoma and the glioblastoma stem cells might be the main reason why conventional therapies fail. The second messenger cyclic AMP (cAMP) controls cell proliferation, differentiation, and apoptosis. Downregulation of cAMP sensitizes tumor cells for an...

NMR methods provide information about conformational dynamics of GPCRs over a wide range frequencies in aqueous media at near-physiological temperature, with minimal modification the wild-type GPCR covalent structures. Here we review our solution studies functionrelated GPCRs, including β2 adrenergic receptor, μ opioid and adenosine A2A receptor.

BACKGROUND Selective kappa opioid receptor antagonism is a promising experimental strategy for the treatment of depression. The kappa opioid receptor antagonist, LY2456302, exhibits ~30-fold higher affinity for kappa opioid receptors over mu opioid receptors, which is the next closest identified pharmacology. METHODS Here, we determined kappa opioid receptor pharmacological selectivity of LY2...

Activation by opioid receptors of cell proliferation was examined with fibroblast cell lines stably expressing either delta-opioid or mu-opioid receptors. Addition of [D-Ala2, D-Leu5]-enkephalin or [D-Pen2,D-Pen5]-enkephalin to Chinese hamster ovary (CHO) cells transfected with delta-opioid receptor cDNA resulted in an agonist concentration-dependent potentiation of fetal calf serum (FCS)-stimu...

Zhu M, Cho YK, Li C-S. Activation of -opioid receptors reduces excitatory input to putative gustatory cells within the nucleus of the solitary tract. J Neurophysiol 101: 258–268, 2009. First published November 19, 2008; doi:10.1152/jn.90648.2008. The rostral nucleus of the solitary tract (NST) is the first central relay in the gustatory pathway and plays a key role in processing and modulation ...

Glutamate neurotransmission plays an important role in the processing of pain and in chronic opioid-induced neural and behavioral plasticity, such as opioid withdrawal and opioid dependence. -Opioid receptors also have been implicated in acute opioid modulation of pain and chronic opioid-induced plasticity, both of which are primarily mediated by -opioid receptors. Using whole-cell patch clamp ...

Chronic treatment with opioid receptor antagonists has been shown to increase the density of micro-, delta- and kappa-opioid receptors in cell culture and in the intact animal. Although opioid receptor antagonist-induced up-regulation is a robust phenomenon, the mechanisms responsible for the increase in receptor density remain unclear. In the present study, changes in a kinase and a GTPase tha...

Three types of opioid receptors exist in the animals, each is encoded by a single gene, i.e., the mu opioid receptor gene, the delta opioid receptor gene, and the kappa opioid receptor gene. However, each opioid receptor gene produces multiple mRNA variants as a result of alternative promoter usages, splicing and/or polyadenylation. As such, a large reservoir of regulatory events has evolved fo...

The rostral nucleus of the solitary tract (NST) is the first central relay in the gustatory pathway and plays a key role in processing and modulation of gustatory information. Here, we investigated the effects of opioid receptor agonists and antagonists on synaptic responses of the gustatory parabrachial nuclei (PbN)-projecting neurons in the rostral NST to electrical stimulation of the solitar...