title: An immunocytochemical study of a G-protein-gated inward rectifier K+ channel (GIRK2) in the weaver mouse mesencephalon.
abstract: It has been suggested that a mutation in a G-protein-gated inward rectifier K+ channel (GIRK2) is responsible for inducing cell death in the cerebellum of homozygous weaver (wv/wv) mutant mice. These mice also display a progressive, massive loss of mesencephalic dopaminergic neurones. Using an immunocytochemical method, we detected GIRK2-positive cell bodies and fibres in the substantia nigra pars compacta (SNC) and the ventral tegmental area (VTA) of control (+/+) mice. Cell counts of both GIRK2- and tyrosine hydroxylase (TH)-positive neurones demonstrated a marked loss of SNC cell bodies, especially in 12-month-old (12M) wv/wv mice. A considerable proportion of GIRK2-positive cell bodies were preserved, however. In addition, no loss of GIRK2-positive neurones was observed in the VTA of 12M wv/wv mice, despite of a significant reduction in TH-positive cell bodies. These results suggest that expression of the mutated channel is not a sufficient condition to induce cell death in the ventral mesencephalon of the wv/wv mice.
authors.affiliation: INSERM U289, Hôpital de la Sâlpêtrière, Paris.
authors.forename: C
authors.initials: C
authors.lastname: Adelbrecht
authors.forename: M G
authors.initials: MG
authors.lastname: Murer
authors.forename: I
authors.initials: I
authors.lastname: Lauritzen
authors.forename: F
authors.initials: F
authors.lastname: Lesage
authors.forename: M
authors.initials: M
authors.lastname: Ladzunski
authors.forename: Y
authors.initials: Y
authors.lastname: Agid
authors.forename: R
authors.initials: R
authors.lastname: Raisman-Vozari
mesh_terms: D000375:Aging / Q000502:physiology; D000818:Animals; D015415:Biomarkers; D051676:G Protein-Coupled Inwardly-Rectifying Potassium Channels; D019204:GTP-Binding Proteins / Q000032:analysis; D007150:Immunohistochemistry; D008297:Male; D008636:Mesencephalon / Q000166:cytology* / Q000254:growth & development; D051379:Mice; D008818:Mice, Neurologic Mutants; D009412:Nerve Fibers / Q000648:ultrastructure; D009474:Neurons / Q000166:cytology*; D015221:Potassium Channels / Q000032:analysis*; D024661:Potassium Channels, Inwardly Rectifying; D012016:Reference Values; D013378:Substantia Nigra / Q000166:cytology / Q000254:growth & development; D013681:Tegmentum Mesencephali / Q000166:cytology / Q000254:growth & development; D014446:Tyrosine 3-Monooxygenase / Q000032:analysis
chemical_list: D015415:Biomarkers; D051676:G Protein-Coupled Inwardly-Rectifying Potassium Channels; D015221:Potassium Channels; D024661:Potassium Channels, Inwardly Rectifying; D014446:Tyrosine 3-Monooxygenase; D019204:GTP-Binding Proteins