Abstract
A series of well-described anabolic and catabolic neuropeptides are known to provide short-term, homeostatic control of energy balance. The mechanisms that govern long-term, rheostatic control of regulated changes in energy balance are less well characterized. Using the robust and repeatable seasonal changes in body mass observed in Siberian hamsters, this report examined the role of prolactin in providing long-term rheostatic control of body mass and photoinduced changes in organ mass (ie, kidney, brown adipose tissue, uterine, and spleen). Endogenous circannual interval timing was observed after 4 months in a short photoperiod, indicated by a significant increase in body mass and prolactin mRNA expression in the pituitary gland. There was an inverse relationship between body mass and the expression of somatostatin (Sst) and cocaine- and amphetamine-regulated transcript (Cart). Pharmacological inhibition of prolactin release (via bromocriptine injection), reduced body mass of animals maintained in long photoperiods to winter-short photoperiod levels and was associated with a significant increase in hypothalamic Cart expression. Administration of ovine prolactin significantly increased body mass 24 hours after a single injection and the effect persisted after 3 consecutive daily injections. The data indicate that prolactin has pleiotropic effects on homeostatic sensors of energy balance (ie, Cart) and physiological effectors (ie, kidney, BAT). We propose that prolactin release from the pituitary gland acts as an output signal of the hypothalamic rheostat controller to regulate adaptive changes in body mass.
Original language | English |
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Article number | bqae020 |
Pages (from-to) | 1-11 |
Number of pages | 11 |
Journal | Endocrinology |
Volume | 165 |
Issue number | 4 |
Early online date | 28 Feb 2024 |
DOIs | |
Publication status | Published - Apr 2024 |
Bibliographical note
The research was funded by the Leverhulme Trust Research Leader award RL-2019-006 to T.J.S. The hamster icon used in Figs. 1-3 was obtained from BioRender. Figure 4 was created using BioRender Software.Data Availability Statement
All datasets generated during and/or analyzed during the cur-rent study are publicly available (38) or presented in
Supplementary Table S2.
Keywords
- Cricetinae
- Animals
- Sheep
- Female
- Prolactin/metabolism
- Seasons
- Hypothalamus/metabolism
- Phodopus/metabolism
- Neuropeptides/metabolism
- Photoperiod