Expression of the novel galanin receptor subtype GALR2 in the adult rat CNS: distinct distribution from GALR1.

Recent molecular cloning studies by our laboratory and others have identified the existence of a novel rat galanin receptor subtype, GALR2. In the present study, we examined the regional and cellular distribution of GALR2 mRNA in the rat central nervous system (CNS) by in situ hybridization. For comparative purposes, adjacent sections were probed for GALR1 mRNA expression.

Cloning and evaluation of the role of rat GALR-2, a novel subtype of galanin receptor, in the control of pain perception.

We have identified a novel subtype of galanin receptor (GALR-2) in rat dorsal root ganglia and spinal cord. The open reading frame of GALR-2 is 1116 nucleotides long, encoding a protein of 372 amino acids with a theoretical molecular mass of 40.7 kD.

Cloning and characterization of a cDNA encoding a novel subtype of rat thyrotropin-releasing hormone receptor.

A cDNA encoding a thyrotropin-releasing hormone (TRH) receptor expressed in the pituitary was previously cloned (De La Pena, P., Delgado, L. M.

Intrathecal administration of the mGluR compound, (S)-4CPG, attenuates hyperalgesia and allodynia associated with sciatic nerve constriction injury in rats.

The present study examined the effects of intrathecal (i.t.) treatment (twice-daily injections on post-operative (PO) days 0-8) with the metabotropic glutamate receptor (mGluR) compound, (S)-4-carboxyphenylglycine ((S)-4CPG), or the non-competitive N-methyl-D-aspartate (NMDA) antagonist, dizocilipine maleate (MK-801), on mechanical allodynia and cold hyperalgesia associated with chronic constriction injury (CCI) of the sciatic nerve in rats.

Kinins and their receptors in hyperalgesia.

Kinins (bradykinin, kallidin) are produced at sites of injury and inflammation and serve a critical role in signaling tissue distress as well as organising tissue responsiveness to injury. The acute activation and prolonged sensitization of fine afferents, to produce pain and hyperalgesia, are important in the protective responses that occur to minimize further tissue injury. These effects occur via activation of B2 receptors present on sensory neurons, resulting in a change of membrane excitability and altered cellular neurochemistry.

Novel "restoration of function" mutagenesis strategy to identify amino acids of the delta-opioid receptor involved in ligand binding.

A novel "restoration of function" mutagenesis strategy was developed to identify amino acid sequence combinations necessary to restore the ability to bind delta-selective ligands to an inactive delta/mu receptor chimera in which 10 amino acids of the third extracellular loop of the delta receptor were replaced by the corresponding amino acids from the mu receptor (delta/mu291-300). This chimera binds a nonselective opioid ligand but is devoid of affinity for delta-selective ligands. A library of mutants was generated in which some of the 10 amino acids of the mu sequence of delta/mu291-300 were randomly reverted to the corresponding delta amino acid.