Fetal Antigen 1 in Healthy Adults and Patients with Pituitary Disease: Relation to Physiological, Pathological, and Pharmacological GH Levels

Immunohistochemical analysis of the distribution of human fetal antigen 1 (FA1) in adult human tissues has demonstrated a strong association between FA1 and (neuro)endocrine structures. In the anterior pituitary gland FA1 was colocalized with GH, and the present study was performed to evaluate a possible relationship between GH and FA1. FA1 and GH levels were measured during a 24-h period at 20-min intervals. In contrast to the known GH peaks during 24-h sampling, there was no detectable FA1 peak. The FA1 responses to placebo were not significantly different from the responses to the combination of pyridostigmine and GHRH. No significant difference was found between basal FA1 (nanograms per ml) levels [median (minimum–maximum)] in healthy adults [n = 40; 28.6 ng/ml (12.5–72.0)], acromegalic patients [n = 11; 31.0 ng/ml (21.6–56.3)], and patients with GH deficiency [n = 22; 32.1 ng/ml (13.4–108.7)]. FA1 levels were significantly reduced, in the six of seven acromegalic GH responders to octreotide, from [me...