title: Modulation of morphine analgesia in alphaCGRP mutant mice.
abstract: A homozygous CGRP-/- mouse line was generated by the targeted disruption of exon 5 in the calcitonin/alphaCGRP gene using homologous recombination. The mutant mice lack alphaCGRP mRNA. Furthermore CGRP immunoreactivity almost completely disappears from the spinal cord and is not at all observed in spinal ganglia and muscle synapses. However, motor end plates were still detected by acetylcholinesterase staining. Antinociceptive behavior tested by the tail flick and hot plate tests did not significantly differ in mutant and wild-type mice, except when challenged by morphine. Paradoxically, morphine analgesia was reduced in mutant mice compared with controls in the tail flick test, but not in the hot plate test. Thus, alphaCGRP differentially modulates opiate pain pathways.
authors: CNRS UA D1284 Neurobiologie Moléculaire, Institut Pasteur, Paris, France.
authors: A M
authors: AM
authors: Salmon
authors: I
authors: I
authors: Damaj
authors: S
authors: S
authors: Sekine
authors: M R
authors: MR
authors: Picciotto
authors: L
authors: L
authors: Marubio
authors: J P
authors: JP
authors: Changeux
mesh_terms: D000701:Analgesics, Opioid / Q000494:pharmacology*; D000818:Animals; D001522:Behavior, Animal / Q000187:drug effects; D015139:Blotting, Southern; D015153:Blotting, Western; D015740:Calcitonin Gene-Related Peptide / Q000235:genetics*; D015247:Deoxyribonuclease HindIII / Q000378:metabolism; D005260:Female; D016678:Genome; D006358:Hot Temperature; D007150:Immunohistochemistry; D008297:Male; D051379:Mice; D009020:Morphine / Q000494:pharmacology*; D009154:Mutation / Q000502:physiology; D010147:Pain Measurement / Q000187:drug effects; D012313:RNA / Q000032:analysis / Q000235:genetics; D015183:Restriction Mapping
chemical_list: D000701:Analgesics, Opioid; D012313:RNA; D009020:Morphine; D015247:Deoxyribonuclease HindIII; D015740:Calcitonin Gene-Related Peptide