The Feldberg and Myers (8, 9) hypothesis concerning body temperature
regulation asserts that the delicate balance between heat production and heat loss is maintained
by the relative activity of serotonin and noradrenalin neurons located in the anterior
hypothalamus. This hypothesis is consistent with observations in several species of animals
and birds since 1964, but not yet in man.
In a therapeutic trial of l-tryptophan in schizophrenia, adequate doses of an MAOI
drug and l-tryptophan were administered sequentially to seven human females, with the
object of fostering the accumulation of predominantly noradrenalin in the brain by the
former and exclusively of serotonin by the latter. Rectal temperatures were measured twice
daily.
It was found that the MAOI drug alone brought about a fall in body temperature
whereas the MAOI drug combined with l-tryptophan caused a rise in the majority of patients.