Dynamic testing of prolactin and growth hormone secretion in patients with neuroendocrine disorders

Prolactin (Prl) and growth hormone (GH) responses to different pharmacologic probes acting at the central nervous system (CNS) or the anterior pituitary (AP) level were evaluated in patients with distinct neuro-endocrine disorders. Thirteen patients with Prl-secreting tumours (PST), 10 acromegalics (A) and 8 patients with hypothalamic lesions (HL), as assessed on clinical, radiological and surgical grounds, underwent on separate occasions acute testing with the opioid peptide FK 33-824 (0.5 mg iv), the indirect dopamine (DA) agonist nomifensine (NOM, 200 mg po), the DA receptor antagonist domperidone (DOM, 10 mg iv), TRH (200 microgram iv) and insulin (ITT, 0.10-0.15 IU/kg iv). All patients were evaluated pre-surgery and 4 of them also post-surgery. Prl and GH were evaluated by RIA at different time intervals following treatments.