Is the naked mole-rat Hererocephalus glaber an endothermic yet poikilothermic mammal?

No oxygen? No problem! Intrinsic brain tolerance to hypoxia in vertebrates

“…Because most of these measurements are for burrows of solitary animals or small colonies, levels in large colonies of naked mole-rats may reach even more extreme values. Consistent with living in an oxygen-deprived environment, naked mole-rats have high-O 2 -affinity hemoglobin (Johansen et al, 1976), and a low resting metabolism (Buffenstein and Yahav, 1991). In addition to the chronic environmental hypoxia of fossorial life, naked mole-rats also experience acute hypoxia during certain behaviors such as foraging and tunnel excavation.…”

Cellular Basis for Learning Impairment in Fragile X Syndrome

“…Freshwater turtles, being coldblooded, are clearly subject to suppressed cellular metabolism when ponds freeze over; hibernation is associated with hypothermia in arctic ground squirrels. Naked mole-rats are the only mammals with significantly reduced body temperature (28°C) in their thermostable natural habitat; physiological thermoregulation is very poor in these animals (Buffenstein and Yahav, 1991;McNab, 1979). Aside from the effect on metabolic rate, the significance of hypothermia in naked mole-rats on brain hypoxia tolerance is less clear.…”

“…African naked mole-rats (Heterocephalus glaber), are unusual even among other subterranean and other mole-rat species. Most notably, they are coldblooded (Buffenstein and Yahav, 1991), they are the longest-lived rodent known -with lifespans exceeding 30 years (Buffenstein, 2008) -and they live in a eusocial structure similar to ants and bees (Jarvis, 1981). A key aspect of the naked mole-rat's lifestyle in the context of our investigations is that they live in colonies with a great many individuals, some colonies having more than 300 members (Brett, 1991).…”

“…For example, peripheral insensitivity to chemical irritants (LaVinka et al, 2009), lack of a functional substance P nociceptive pathway (Park et al, 2003), poor thermoregulation (Buffenstein and Yahav, 1991), absence of fur, and high-affinity hemoglobin (Johansen et al, 1976) may all be juvenile characteristics retained into adulthood. Slowed or arrested development might even contribute to the extraordinary lifespan (Buffenstein, 2008) of these remarkable animals.…”

“…Because most of these measurements are for burrows of solitary animals or small colonies, levels in large colonies of naked mole-rats may reach even more extreme values. Consistent with living in an oxygen-deprived environment, naked mole-rats have high-O 2 -affinity hemoglobin (Johansen et al, 1976), and a low resting metabolism (Buffenstein and Yahav, 1991). In addition to the chronic environmental hypoxia of fossorial life, naked mole-rats also experience acute hypoxia during certain behaviors such as foraging and tunnel excavation.…”