We studied the
luteinizing hormone (LH),
follicle stimulating hormone (FSH) and
growth hormone (GH) secretion following an i.v. injection of 0.1 mg of
luteinizing hormone releasing hormone (
LHRH) in patients with
anorexia nervosa, who showed the GH secretion after
thyrotropin releasing hormone (TRH). Five out of 11 patients had an elevated plasma GH level in a fasting state. The administration of
LHRH resulted in a significant increase in the plasma GH concentrations in 3 of the 11 patients. Three other patients also showed an elevation of the plasma GH concentration to 7.0, 18.4 and 29.6 ng/ml, which were 212, 175 and 191% of the preinjection levels, respectively. There is a positive correlation between the basal and peak plasma GH levels after
LHRH. These increases, however, were related to neither the plasma
gonadotropin responses to
LHRH nor the plasma GH responses to TRH. The basal levels of plasma LH were reduced in 8 patients and normal responses to
LHRH were observed in only one patient. Although plasma FSH was undetectable in 5 patients, the FSH response to
LHRH appeared normal in 9 patients. These results indicate that an elevation of the plasma GH level after
LHRH is not confined to patients with a GH secreting
pituitary tumor but observed in subjects with
anorexia nervosa and further suggest that the GH responsiveness to non-specific
hypothalamic releasing hormones may be due to the impaired hypothalamic control in
anorexia nervosa.