Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: EC:3.1.26.9 (ribonuclease)
 6,589 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The distribution of rat vasoactive intestinal peptide2 (VIP2) receptor messenger RNA in the brain and the pituitary gland was examined by in situ hybridization and by ribonuclease protection assay. labelled cells were found chiefly in the suprachiasmatic nucleus, the central nucleus of the amygdala and the thalamus (the lateral geniculate nucleus, and the paraventricular, mediodorsal and ventral nuclei of the thalamus). The distribution of the VIP2 receptor overlaps only in part with that of the VIP1 receptor, for example in the hippocampus, where VIP2 receptor messenger RNA was found in the pyramidal cells of the CA1-CA3 subfields and in the granule cells of the dentate gyrus. Small numbers of neurons containing high concentrations of VIP2 receptor messenger RNA were present in the brainstem in the principal sensory trigeminal nucleus and in the substantia gelatinosa of the spinal cord, suggesting a role for the VIP2 receptor in the processing of sensory information. The presence of the VIP2 receptor in the suprachiasmatic nucleus suggests that it is this receptor subtype which is involved in the control of circadian rhythms.
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PMID:The distribution of vasoactive intestinal peptide2 receptor messenger RNA in the rat brain and pituitary gland as assessed by in situ hybridization. 767 76

Vasoactive intestinal peptide (VIP) is a neuromediator expressed widely in the nervous, gastrointestinal, respiratory, and immune systems. Two G protein-coupled receptors (GPCRs), designated VPAC1 and VPAC2, bind VIP with high affinity and transduce increases in [cyclic AMP](i) and [Ca(2+)](i). As there are no potent VPAC1- or VPAC2-selective antagonists, a hammerhead ribozyme (Rz) strategy capable of in vivo application was adopted to inactivate individual domains of VPAC1. Three Rzs were designed to cleave mRNA encoding the amino terminus, the third intracellular loop, and the cytoplasmic tail of human VPAC1 and were introduced by transfection into HEK-293 cells expressing recombinant human VPAC1. Each Rz specifically degraded VPAC1 mRNA and down-regulated VPAC1 protein and VIP-binding activity, as assessed by ribonuclease protection assays, Western blots, and binding of (125)I-VIP. Rz-mediated down-regulation of VPAC1 was associated with up to 75% suppression of VIP signaling of increases in [cyclic AMP](i) and [IP3](i), and of cyclic AMP response element-luciferase reports. The Rz specific for the amino terminus inhibited VPAC1 expression and signaling to the greatest extent. VIP-evoked cellular responses thus appear to be proportional to the level of VPAC1 expression. Specific Rzs may be powerful tools for manipulating tissue-specific contributions of GPCRs in vitro and in vivo.
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PMID:Inhibition of expression of the type I G protein-coupled receptor for vasoactive intestinal peptide (VPAC1) by hammerhead ribozymes. 1093 94