Specific binding of synthetic human pancreatic growth hormone releasing factor (1-40-OH) to bovine anterior pituitaries.
We have studied the specific binding of a synthetic 40 amino acid, free carboxy terminus analog of human pancreatic growth hormone releasing factor (hp GRF-40-OH) to partially purified homogenates of bovine anterior pituitaries. The binding of hpGRF-40-OH to pituitary receptors at 4 degrees C reached maximal level in 4 hours and remained steady for the next 18 hours. Specific binding increased linearly with the amount of protein present in the assay. 125I-hpGRF-40-OH binding to pituitary homogenates was competitively inhibited by hpGRF-40-OH but not by unrelated hormones. The competition curve and Scatchard analysis suggest the presence of single class of receptors with a Kd congruent to 3nM and binding capacity of approximately 200 fmoles/mg protein. This is the first demonstration of specific receptors for GRF on anterior pituitary cells.
Veliçelebi
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G
Santacroce
T M
TM
Harpold
M M
MM
D000595:Amino Acid Sequence; D000818:Animals; D001667:Binding, Competitive; D002417:Cattle; D013007:Growth Hormone-Releasing Hormone / Q000378:metabolism*; D007700:Kinetics; D010446:Peptide Fragments / Q000378:metabolism*; D010903:Pituitary Gland, Anterior / Q000378:metabolism*; D051381:Rats; D011956:Receptors, Cell Surface / Q000378:metabolism*; D011986:Receptors, Somatotropin
D010446:Peptide Fragments; D011956:Receptors, Cell Surface; D011986:Receptors, Somatotropin; C036893:somatotropin releasing factor 40; D013007:Growth Hormone-Releasing Hormone