| First Author | Morton GJ | Year | 2011 |
| Journal | Am J Physiol Endocrinol Metab | Volume | 300 |
| Issue | 2 | Pages | E392-401 |
| PubMed ID | 21062956 | Mgi Jnum | J:172324 |
| Mgi Id | MGI:5006916 | Doi | 10.1152/ajpendo.00546.2010 |
| Citation | Morton GJ, et al. (2011) Identification of a physiological role for leptin in the regulation of ambulatory activity and wheel running in mice. Am J Physiol Endocrinol Metab 300(2):E392-401 |
| abstractText | Mechanisms regulating spontaneous physical activity remain poorly characterized despite evidence of influential genetic and acquired factors. We evaluated ambulatory activity and wheel running in leptin-deficient ob/ob mice and in wild-type mice rendered hypoleptinemic by fasting in both the presence and absence of subcutaneous leptin administration. In ob/ob mice, leptin treatment to plasma levels characteristic of wild-type mice acutely increased both ambulatory activity (by 4,000 +/- 200 beam breaks/dark cycle, P < 0.05) and total energy expenditure (TEE; by 0.11 +/- 0.01 kcal/h during the dark cycle, P < 0.05) in a dose-dependent manner and acutely increased wheel running (+350%, P < 0.05). Fasting potently increased ambulatory activity and wheel running in wild-type mice (AA: +25%, P < 0.05; wheel running: +80%, P < 0.05), and the effect of fasting was more pronounced in ob/ob mice (AA: +400%, P < 0.05; wheel running: +1,600%, P < 0.05). However, unlike what occurred in ad libitum-fed ob/ob mice, physiological leptin replacement attenuated or prevented fasting-induced increases of ambulatory activity and wheel running in both wild-type and ob/ob mice. Thus, plasma leptin is a physiological regulator of spontaneous physical activity, but the nature of leptin's effect on activity is dependent on food availability. |
