Effect of ergot alkaloids on growth hormone and prolactin secretion in humans

The effects of ergot alkaloids (mainly bromocriptine) on the secretion of GH and PRL in normal subjects and in pathological conditions (i.e. acromegaly and hyperprolactinemic states) are discussed. In the normal subjects, bromocriptine releases GH whereas in about 50% of acromegalics it causes a marked and long-lasting inhibition of the hormone secretion. PRL release is reduced by the drug both in normal subjects and in hyperprolactinemic states. Physiopathological studies in the humans indicate that, according to the experimental data, bromocriptine inhibits GH release in acromegaly and PRL secretion through a dopaminergic mechanism of action playing at the pituitary level. Data are reported on the effectiveness of bromocriptine in the medical treatment of acromegaly and of hyperprolactinemic states.