title: Comparison of c-Fos expression in brain regions involved in maternal behavior of virgin and lactating female mice.
abstract: Maternal care is indispensable for the survival of mammalian offspring. Although virgin female mice avoid pups, they actively display maternal behavior after parturition. To determine which brain regions are involved in the qualitative differences observed in the responses of virgin and lactating females to pups, we compared the expression of c-Fos, which is a marker of neuronal activation, in brain regions involved in regulating maternal behavior. Pup presentation increased the number of c-Fos-positive cells in both the ventrotegmental area (VTA) and nucleus accumbens to a greater extent in lactating females than in virgin females. The bed nucleus of striaterminalis (BNST), which innervates VTA neurons to regulate both aversive and rewarding responses, showed increased number of c-Fos-positive cells following pup presentation in virgin females, butnotin lactating females. On the other hand, the number of c-Fos-positive cells in the medial preoptic area (MPOA) increased in both virgin and lactating females. The number of c-Fos-positive cells in lactating females not presented with pups was high and similar to that in virgin females presented with pups. Moreover, c-Fos-positive GABAergicneurons projecting from the MPOA to the BNST was confirmed using a retrograde tracer Fluorogold in lactating females. Our results indicate that constitutive GABAergic modulation projecting from the MPOA may suppress the activity of BNST neurons and prevent avoidance responses to pups in lactating females.
authors: Department of Basic Veterinary Medicine, Obihiro University of Agriculture and Veterinary Medicine, Obihiro, Hokkaido 080-8555, Japan.
authors: Nao
authors: N
authors: Matsushita
authors: Department of Basic Veterinary Medicine, Obihiro University of Agriculture and Veterinary Medicine, Obihiro, Hokkaido 080-8555, Japan. Electronic address: muroi@obihiro.ac.jp.
authors: Yoshikage
authors: Y
authors: Muroi
authors: Department of Basic Veterinary Medicine, Obihiro University of Agriculture and Veterinary Medicine, Obihiro, Hokkaido 080-8555, Japan.
authors: Ken-ichi
authors: K
authors: Kinoshita
authors: Department of Basic Veterinary Medicine, Obihiro University of Agriculture and Veterinary Medicine, Obihiro, Hokkaido 080-8555, Japan.
authors: Toshiaki
authors: T
authors: Ishii
mesh_terms: D000818:Animals; D015415:Biomarkers / Q000378:metabolism; D001921:Brain / Q000033:anatomy & histology / Q000378:metabolism*; D002452:Cell Count; D007774:Lactation / Q000523:psychology*; D008425:Maternal Behavior; D008807:Mice, Inbred BALB C; D009474:Neurons / Q000166:cytology / Q000378:metabolism; D011301:Preoptic Area / Q000378:metabolism; D016760:Proto-Oncogene Proteins c-fos / Q000378:metabolism*; D012686:Septal Nuclei / Q000378:metabolism
chemical_list: D015415:Biomarkers; D016760:Proto-Oncogene Proteins c-fos
keywords: Bed nucleus of striaterminalis; Maternal behavior; Medial preoptic area; Nucleus accumbens; Ventrotegmental area; c-Fos