When nonshivering thermogenesis equals maximum metabolic rate

Simple item page
dc.contributor.authorNespolo, RF
dc.contributor.authorBacigalupe, LD
dc.contributor.authorRezende, EL
dc.contributor.authorBozinovic, F
dc.date.accessioned2025-01-21T01:30:52Z
dc.date.available2025-01-21T01:30:52Z
dc.date.issued2001
dc.description.abstractMany small mammals inhabiting fluctuating and cold environments display enhanced capacity for seasonal changes in nonshivering thermogenesis (NST) and thermoregulatory maximum metabolic rate (MMR). However, it is not known how this plasticity remains in a mammal that rarely experiences extreme thermal fluctuations. In order to answer this question, we determined body mass (m(b)), basal metabolic rate (BMR), NST, MMR, and minimum thermal conductance (C) on a Chilean fossorial caviomorph (Spalacopus cyanus) from a coastal population, acclimated to cold (15 degreesC) and warm (30 degreesC) conditions. NST was measured as the maximum response of metabolic rate (NSTmax) after injection of norepinephrine (NE) in thermoneutrality minus BMR. Maximum metabolic rate was assessed in animals exposed to enhanced heat-loss atmosphere (He-O-2) connected with an open-flow respirometer. Body mass and metabolic variables increased significantly after cold acclimation with respect to warm acclimation but to a low extent (BMR, 26%; NST, 10%; and MMR, 12%). However, aerobic scope (MMR/BMR), calculated shivering thermogenesis (ST), and C did not change with acclimation regime. Our data suggest that physiological plasticity of S. cyanus is relatively low, which is in accordance with a fossorial mode of life. Although little is known about MMR and NST in fossorial mammals, S. cyanus has remarkably high NST; low MMR; and surprisingly, a nil capacity of ST when compared with other rodents.
dc.fuente.origenWOS
dc.identifier.eissn1537-5293
dc.identifier.issn1522-2152
dc.identifier.urihttps://repositorio.uc.cl/handle/11534/96918
dc.identifier.wosidWOS:000169015000002
dc.issue.numero3
dc.language.isoen
dc.pagina.final332
dc.pagina.inicio325
dc.revistaPhysiological and biochemical zoology
dc.rightsacceso restringido
dc.subject.ods13 Climate Action
dc.subject.ods15 Life on Land
dc.subject.odspa13 Acción por el clima
dc.subject.odspa15 Vida de ecosistemas terrestres
dc.titleWhen nonshivering thermogenesis equals maximum metabolic rate
dc.typeartículo
dc.volumen74
sipa.indexWOS
sipa.trazabilidadWOS;2025-01-12
Files
Collections
Artículos de revistas