Suckling Dysfunction Caused by Defects in the Olfactory System in Genetic Arhinencephaly Mice

Abstract

Mouse newborns find their mother’s nipples and suckle milk by themselves. It has been argued which sense organ they use when locating their mother’s nipples to suckle milk. Olfactory or tactile sensory systems are primary candidates. In the present study, we investigated the trigeminal-whisker sensory and olfactory systems in genetic arhinencephaly mouse embryos (Pdn/Pdn). Pdn/Pdn newborns do not suckle milk and die within 1 day after birth. Dysfunction of nipple-searching behavior was clear in Pdn/Pdn newborns. Pdn/Pdn newborns had a complete developmental failure in the olfactory nerve projection to the central nervous system and no olfactory bulb architecture. The trigeminal-whisker system was intact in this strain. From the results of these experiments, it was suggested that the olfactory system is essential for nipple-searching behavior and suckling milk and that the trigeminal-whisker system is not able to substitute for the lack of olfactory input in mouse newborns.

Recognition of H3K9 methylation by GLP is required for efficient establishment of H3K9 methylation, rapid target gene repression, and mouse viability

“…Although no drastic abnormalities of the main organs were observed and no catastrophic events occurred in breathing and heart beating, we consistently observed that no milk was present in the stomachs of GLP M/M pups, so it was highly possible that GLP M/M mice died of starvation. To understand at which stage the GLP M/M pups failed to be fed, we adapted an assay to dissect multiple steps of suckling processes (Hongo et al 2000). The GLP M/M mice were capable of actively searching and licking the nipples of mother mice (Fig.…”

“…Mouse suckling assays were adapted from previous studies (Hongo et al 2000). Briefly, shortly after giving birth to newborns, female mice were given 0.05 mg/g pentobarbital sodium intraperitoneally for anesthesia and laid on a heating block (37°C).…”

Trio Is a Key Guanine Nucleotide Exchange Factor Coordinating Regulation of the Migration and Morphogenesis of Granule Cells in the Developing Cerebellum

“…1, C-F). This defect may account for the failure to suckle milk (29). The hippocampus also showed a disorganized structure in the dentate gyrus (Fig.…”

Olfactory Evaluation in Children: Application to the CHARGE Syndrome

“…9,10 In mice, olfaction is crucial at birth to lead the pups to their mother's nipples, and anosmic mice die shortly after birth because they cannot find them. 11 All of these data suggest that human neonatal olfaction probably plays a role both in mother-child bonding and in newborns' feeding behavior. During the first years of life, the role of olfaction is probably important, although few studies have demonstrated this, principally because olfaction evaluation is difficult in this age range.…”