title: Somatomedin levels in cerebrospinal fluid from adults with pituitary disorders.
abstract: Somatomedin levels in cerebrospinal fluid (CSF) were determined in patients with acromegaly, pituitary deficiency, prolactinoma, and Cushing's disease by radioimmunoassay (RIA) for insulin-like growth factor 1 (IGF-1) and for IGF-2 as well as a radioreceptor assay (RRA) with adult human brain plasma membranes and IGF-2 as ligand. The mean value of RIA-IGF-2 (31 +/- 1.6 ng/ml) predominated over that of RIA-IGF-1 (5.8 +/- 0.3 ng/ml), but 10 times higher levels were found by RRA-IGF-2. Patients with acromegaly were not found to have higher values than those with GH deficiency even after corrections were made for possible leakage across the blood-CSF barrier. No correlations were found between CSF somatomedin levels determined by different techniques and immunoreactive IGF-1 or GH in the peripheral circulation except for a positive correlation between CSF RIA-IGF-2 and serum IGF-1 in patients with acromegaly. These findings suggest that somatomedins in CSF consist primarily of IGF-2-like peptides which are derived from production within the central nervous system or pituitary gland rather than from transport across the blood-CSF barrier.
mesh_terms: D000172:Acromegaly / Q000134:cerebrospinal fluid; D000293:Adolescent; D000328:Adult; D000367:Age Factors; D001812:Blood-Brain Barrier; D003480:Cushing Syndrome / Q000134:cerebrospinal fluid; D005260:Female; D013006:Growth Hormone / Q000172:deficiency; D006801:Humans; D007018:Hypopituitarism / Q000134:cerebrospinal fluid; D007328:Insulin / Q000097:blood; D008297:Male; D008875:Middle Aged; D010455:Peptides / Q000097:blood; D010900:Pituitary Diseases / Q000134:cerebrospinal fluid*; D010911:Pituitary Neoplasms / Q000134:cerebrospinal fluid; D011388:Prolactin / Q000378:metabolism; D011863:Radioimmunoassay; D011869:Radioligand Assay; D013002:Somatomedins / Q000097:blood / Q000134:cerebrospinal fluid*
chemical_list: D007328:Insulin; D010455:Peptides; D013002:Somatomedins; D011388:Prolactin; D013006:Growth Hormone