title: Development-dependent behavioral change toward pups and synaptic transmission in the rhomboid nucleus of the bed nucleus of the stria terminalis.
abstract: Sexually naïve male C57BL/6 mice aggressively bite unfamiliar pups. This behavior, called infanticide, is considered an adaptive reproductive strategy of males of polygamous species. We recently found that the rhomboid nucleus of the bed nucleus of the stria terminalis (BSTrh) is activated during infanticide and that the bilateral excitotoxic lesions of BSTrh suppress infanticidal behavior. Here we show that 3-week-old male C57BL/6 mice rarely engaged in infanticide and instead, provided parental care toward unfamiliar pups, consistent with observations in rats and other rodent species. This inhibition of infanticide at the periweaning period is functional because the next litter will be born at approximately the time of weaning of the previous litter through maternal postpartum ovulation. However, the mechanism of this age-dependent behavioral change is unknown. Therefore, we performed whole-cell patch clamp recordings of BSTrh and compared evoked neurotransmission in response to the stimulation of the stria terminalis of adult and 3-week-old male mice. Although we were unable to detect a significant difference in the amplitudes of inhibitory neurotransmission, the amplitudes and the paired-pulse ratio of evoked excitatory postsynaptic currents differed between adult and 3-week-old mice. These data suggest that maturation of the synaptic terminal in BSTrh that occurred later than 3 weeks after birth may mediate by the adaptive change from parental to infanticidal behavior in male mice.
authors: Laboratory for Affiliative Social Behavior, RIKEN Brain Science Institute, 351-0198, Japan; Department of Pharmacology, Graduate School of Pharmaceutical Sciences, Hokkaido University, 060-0812, Japan. Electronic address: tamano@pharm.hokudai.ac.jp.
authors: Taiju
authors: T
authors: Amano
authors: Laboratory for Affiliative Social Behavior, RIKEN Brain Science Institute, 351-0198, Japan.
authors: Sayaka
authors: S
authors: Shindo
authors: Laboratory for Affiliative Social Behavior, RIKEN Brain Science Institute, 351-0198, Japan.
authors: Chihiro
authors: C
authors: Yoshihara
authors: Laboratory for Affiliative Social Behavior, RIKEN Brain Science Institute, 351-0198, Japan; Department of Anatomy, School of Medicine, Toho University, 143-8540, Japan.
authors: Yousuke
authors: Y
authors: Tsuneoka
authors: Department of Pharmacology, Graduate School of Pharmaceutical Sciences, Hokkaido University, 060-0812, Japan.
authors: Haruka
authors: H
authors: Uki
authors: Department of Pharmacology, Graduate School of Pharmaceutical Sciences, Hokkaido University, 060-0812, Japan.
authors: Masabumi
authors: M
authors: Minami
authors: Laboratory for Affiliative Social Behavior, RIKEN Brain Science Institute, 351-0198, Japan.
authors: Kumi O
authors: KO
authors: Kuroda
mesh_terms: D000367:Age Factors; D000374:Aggression / Q000502:physiology*; D000818:Animals; D001522:Behavior, Animal / Q000502:physiology*; D005071:Evoked Potentials / Q000502:physiology*; D019706:Excitatory Postsynaptic Potentials / Q000502:physiology*; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D018408:Patch-Clamp Techniques; D012686:Septal Nuclei / Q000254:growth & development / Q000502:physiology*
keywords: Aggression; Bed nucleus of the stria terminalis; Development; Electrophysiology; Parental behavior; Social behavior