title: Effect of dopamine infusion on plasma levels of growth hormone in normal subjects and in agromegalic patients.
abstract: In ten normal subjects and in twenty acromegalic patients plasma levels of growth hormone were studied after administration of L-dopa and a dopamine infusion. In the ten normal subjects L-dopa, but not dopamine, increased plasma levels of GH. In the acromegalic patients both L-dopa and dopamine were followed by an inhibition of GH release. Since dopamine does not cross the blood-brain barrier, these results, although not excluding a site of action at median eminence level, support the thesis that the inhibitory effect of dopaminergic stimulation on GH release in acromegaly possibly involves receptors present on GH-secreting cells.
mesh_terms: D000172:Acromegaly / Q000097:blood*; D000328:Adult; D004298:Dopamine / Q000494:pharmacology*; D005260:Female; D013006:Growth Hormone / Q000097:blood*; D006801:Humans; D007980:Levodopa / Q000494:pharmacology*; D008297:Male; D008875:Middle Aged; D010902:Pituitary Gland / Q000187:drug effects
chemical_list: D007980:Levodopa; D013006:Growth Hormone; D004298:Dopamine