Body temperature and 5‐hydroxytryptamine during early postnatal maturation in mice

Abstract

A relationship between the maturational increases in body temperature and brain indoleamines has been explored through altering brain 5-hydroxytryptamine (5-HT) content. Effects on body temperature at approximately constant ambient temperature (about 24 degrees C) have been studied following pharmacological manipulations in mice up to 16 days postpartum. Administration of 5-hydroxytryptophan (5-HTP) to increase 5-HT levels was associated with decreased body temperature throughout the maturational period. Depletion of 5-HT with p-chlorophenylalanine (p-CPA) was associated with increased body temperature at all ages studied, although 5-HT depletion was less effective in young animals than in older animals. The drug NSD-1034 acts at a different enzymatic step, and is effective in both central and peripheral tissues to reduce 5-HT and norepinephrine (NE) levels. NSD-1034 decreased body temperature up to 10 days of age; however, the effect was reversed at about 14 days, and the drug increased body temperature significantly in 16-day-old animals. These results suggest a role for 5-HT in the mechanisms of heat production in early postnatal life.

Gut microbiota intervention attenuates thermogenesis in broilers exposed to high temperature through modulation of the hypothalamic 5-HT pathway

“…In addition, the functions of central and peripheral 5-HT differ, with hypothalamic 5-HT serving as an important neurotransmitter involved in regulating physiological processes such as sleep, emotion, and body temperature [ 74 – 76 ]. It has been reported that the tryptophan–5-HT metabolic pathway in the hypothalamus is involved in the regulation of brain neurotransmitters, and central 5-HT administration can activate 5-HTergic neurons to cause hypothermia in mice and chicks [ 77 , 78 ]. Exogenous tryptophan supplementation can also increase hypothalamic 5-HT levels, lowering the rectal temperature in broiler chickens and indicating a negative correlation between central 5-HT content and heat production [ 20 ].…”