The Effect of Short-term Cold and Hot Exposure on Total Plasma Ghrelin Concentrations in Humans

Abstract

Ghrelin is one of the peptides involved in the gut-brain axis. This 28-aminoacid peptide is primarily produced in the stomach and small intestine [1]. The first role of ghrelin to be determined involved the release of growth hormone [2], but later, the focus was placed on the role of this peptide in eating behavior and weight regulation [3] [4]. Ghrelin is upregulated during fasting; suggestions have been made that ghrelin is a signal of meal initiation [5]. Ambient temperature has been known to be a powerful metabolic regulator since the forties - a high environmental temperature results in decreased food intake, while a low environmental temperature leads to increased food intake [6]; however, the regulatory mechanism responsible for this phenomenon is still unclear. Therefore, the aim of this study was to investigate the relationship between plasma ghrelin levels and environmental temperature.