title: Delayed development of reflexes and hyperactive locomotion in the spontaneous mutant "waltzing" of the musk shrew, Suncus murinus.
abstract: The autosomal recessive mutation waltzing (wz), displaying abnormal circling and head-shaking behavior, has previously been reported in the musk shrew (Suncus murinus). Postnatal development of reflexes and locomotor patterns in an open arena were examined in wz/wz mutant shrews. The wz/wz shrews showed extreme developmental delays in surface-righting reflex and negative geotaxis until 10-16 days after birth, but both reflexes eventually recovered to the levels of +/wz normal. Nevertheless, the wz/wz adults exhibited bi-directional circling behavior 59 times, head-tossing behavior 22 times and horizontal head-shaking behavior 6 times more frequent than in the +/wz controls. Although the wz/wz adult shrews were extremely hyperactive with daily spontaneous locomotor activity exceeding 4-7 times control shrew activity, they appeared to have a normal circadian rhythm. This shrew mutant may therefore be useful as a model for hyperactivity syndromes in humans.
authors.affiliation: Laboratory of Animal Genetics, Graduate School of Bioagricultural Sciences, Nagoya University, Japan.
authors.forename: A
authors.initials: A
authors.lastname: Matsuura
authors.forename: T
authors.initials: T
authors.lastname: Ohno
authors.forename: T
authors.initials: T
authors.lastname: Matsushima
authors.forename: T
authors.initials: T
authors.lastname: Namikawa
authors.forename: A
authors.initials: A
authors.lastname: Ishikawa
mesh_terms: D000818:Animals; D001522:Behavior, Animal / Q000502:physiology*; D001835:Body Weight; D002940:Circadian Rhythm; D005260:Female; D008297:Male; D009043:Motor Activity / Q000235:genetics / Q000502:physiology*; D009154:Mutation; D004856:Postural Balance / Q000502:physiology; D012021:Reflex, Abnormal / Q000235:genetics / Q000502:physiology*; D012788:Shrews / Q000235:genetics*