Ms. Blumberg et al., PONTINE AND BASAL FOREBRAIN TRANSECTIONS DISINHIBIT BROWN FAT THERMOGENESIS IN NEONATAL RATS, Brain research, 699(2), 1995, pp. 214-220
Bignall, Heggeness and Palmer (1975) were the first to demonstrate inc
reases in metabolic heat production following midpontine transection i
n neonatal rats. Subsequent work in adult rats has shown that this pro
cedure disinhibits thermogenesis by brown adipose tissue (BAT). Bignal
l and his colleagues also found that hypothalamic ablation did not res
ult in increased thermogenesis in 5-day-olds, leading them to conclude
that thermoregulation depends on more caudal structures at that age.
We have also found that midpontine transection disinhibits BAT thermog
enesis and, furthermore, have extended that finding to newborn pups. W
hen transections were made in the basal forebrain, however, we also fo
und profound and rapid increases in brown fat thermogenesis. These res
ults suggest the presence of at least two sources of inhibition of BAT
thermogenesis in newborn rats: one located in the rostral pons-caudal
midbrain and one located in the basal forebrain.