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Title: Naked mole-rat and Damaraland mole-rat exhibit lower respiration in mitochondria, cellular and organismal levels
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Biochimica et Biophysica Acta (BBA) - Bioenergetics
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National Science Foundation
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    The colonial naked mole ratHeterocephalus glaberis a subterranean, eusocial rodent. TheH. glabervomeronasal organ neuroepithelium (VNE) displays little postnatal growth. However, the VNE remains neuronal in contrast to some mammals that possess nonfunctional vomeronasal organ remnants, for example, catarrhine primates and some bats. Here, we describe the vomeronasal organ (VNO) microanatomy in the naked mole rat and we make preliminary observations to determine ifH. glabershares its minimal postnatal VNE growth with other African mole rats. We also determine the immunoreactivity to the mitotic marker Ki67, growth‐associated protein 43 (GAP43), and olfactory marker protein (OMP) in six adult and three subadultH. glaberindividuals. VNE volume measurements on a small sample ofCryptomys hottentotusandFukomys damarensisindicate that the VNE of those African mole rat species are also likely to be growth‐deficient. Ki67(+) cells show that the sensory epithelium is mitotically active. GAP43 labelling indicates neurogenesis and OMP(+) cells are present though less numerous compared to GAP43(+) cells. In this respect, the VNO ofH. glaberdoes not appear vestigial. The African mole rat VNE may be unusually variable, perhaps reflecting reduced selection pressure on the vomeronasal system. If so, African mole rats may provide a useful genetic model for understanding the morphological variability observed in the mammalian VNO. Anat Rec, 2019. © 2019 Wiley Periodicals, Inc. Anat Rec, 303:318–329, 2020. © 2019 American Association for Anatomy

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