Stimulatory effect of acute baclofen administration on human growth hormone secretion.

The effect of acute administration of the gamma-amino-butyric acid (GABA) derivative, baclofen, on human GH secretion was tested. In eight of the nine volunteers, both 5 and 10 mg baclofen (Lioresal) significantly basal GH secretion. Previoulsy, it has been reported that subacute baclofen treatment inhibits the GH response to insulin hypoglycemia and arginine. Thus, the present study shows that baclofen is able to modify GH secretion via different mechanisms, depending on the test situation and duration of treatment. As a putative GABA agonist, the effect of baclofen may be mediated via GABA-ergic pathways. Because of variable results, the evaluation of a possible physiological role of GABA in GH secretion requires further study.