{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,25]],"date-time":"2026-09-25T06:58:34Z","timestamp":1790319514228,"version":"4.1.0"},"reference-count":43,"publisher":"F1000 Research Ltd","license":[{"start":{"date-parts":[[2026,8,28]],"date-time":"2026-08-28T00:00:00Z","timestamp":1787875200000},"content-version":"tdm","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100000268","name":"Biotechnology and Biological Sciences Research Council","doi-asserted-by":"publisher","award":["BB\/W007266\/1"],"award-info":[{"award-number":["BB\/W007266\/1"]}],"id":[{"id":"10.13039\/501100000268","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/100010269","name":"Wellcome Trust","doi-asserted-by":"publisher","award":["308526"],"award-info":[{"award-number":["308526"]}],"id":[{"id":"10.13039\/100010269","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":["wellcomeopenresearch.org"],"crossmark-restriction":false},"short-container-title":["Wellcome Open Res"],"abstract":"<ns3:p>We argue in this perspective that daily torpor in the mouse, induced by a lack of caloric intake and a relatively cool environment, does not require a dedicated \u201cmaster mediator\u201d for systemic metabolic rate (MR) suppression. Instead, a set of centrally mediated changes, most notably: cessation of physical activity; dramatically reduced thermogenesis, along with a lowering of the defended minimum body temperature (Tb); and, reduced cardiovascular work, together drive the substantial drop in metabolic rate at the initiation of daily torpor in the mouse. That is, rather than invoking a global, organism-wide suppression of metabolism across all tissues, we argue that MR reduction during mouse daily torpor is selective and physiologically organized, targeting a small number of energetically dominant organ systems. Once Tb has declined in response to the initial physiological adaptations, temperature-dependent effects on biochemical reaction rates can account for much of the further reduction in whole-animal MR during the torpid state, resulting in an ultimate fall in MR of 75\u201380% in daily torpor of the mouse. This framework also aligns torpor with the normal ultradian rhythm of sleep-associated reductions in MR and Tb, differing mainly in the much deeper nadir reached.<\/ns3:p>","DOI":"10.12688\/wellcomeopenres.27516.1","type":"journal-article","created":{"date-parts":[[2026,8,28]],"date-time":"2026-08-28T07:29:07Z","timestamp":1787902147000},"page":"561","update-policy":"https:\/\/doi.org\/10.12688\/wellcomeopenres.crossmark-policy","source":"Crossref","is-referenced-by-count":0,"title":["Hot take on a cool topic: is there really a need for a systemic master mediator of metabolic suppression in mouse daily torpor?"],"prefix":"10.12688","volume":"11","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-7884-6522","authenticated-orcid":false,"given":"Mike","family":"Ambler","sequence":"first","affiliation":[{"name":"School of Psychology & Neuroscience Bristol Select... 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