TY - JOUR
T1 - Homologous somatotropin radioreceptor assay utilizing recombinant bovine growth hormone
AU - Haro, Luis S.
AU - Collier, Robert J.
AU - Talamantes, Frank J.
N1 - Funding Information:
This research was supported by NIH Grant RR-08132 and UCSC FRC grant to F.J.T. and by a grant from Monsanto Company to R.J.C.
PY - 1984/12
Y1 - 1984/12
N2 - A homologous radioreceptor assay using recombinant bovine growth hormone and bovine liver membranes is described. The total specific binding of 125I-labeled recombinant bovine growth hormone to the 100000 × g pellet was 48% in 24 h at 25 °C. Hormone binding was partially reversible, with 40% of the radiolabeled hormone being irreversibly bound. The amount of specific binding varied with assay pH, with the optimum occurring at pH 7.8. Specific binding was temperature-dependent, with greater specific binding occurring at 25°C than at 5°C or 37°C during a 24 h period. Recombinant bovine growth hormone, human growth hormone, ovine growth hormone and recombinant porcine growth hormone competed effectively with 125I-labeled recombinant bovine growth hormone for binding sites, while bovine prolactin and ovine prolactin were needed in amounts 106-fold the concentration of recombinant bovine growth hormone to displace the radiolabeled hormone. Surprisingly, human placental lactogen did not displace the radiolabeled hormone.
AB - A homologous radioreceptor assay using recombinant bovine growth hormone and bovine liver membranes is described. The total specific binding of 125I-labeled recombinant bovine growth hormone to the 100000 × g pellet was 48% in 24 h at 25 °C. Hormone binding was partially reversible, with 40% of the radiolabeled hormone being irreversibly bound. The amount of specific binding varied with assay pH, with the optimum occurring at pH 7.8. Specific binding was temperature-dependent, with greater specific binding occurring at 25°C than at 5°C or 37°C during a 24 h period. Recombinant bovine growth hormone, human growth hormone, ovine growth hormone and recombinant porcine growth hormone competed effectively with 125I-labeled recombinant bovine growth hormone for binding sites, while bovine prolactin and ovine prolactin were needed in amounts 106-fold the concentration of recombinant bovine growth hormone to displace the radiolabeled hormone. Surprisingly, human placental lactogen did not displace the radiolabeled hormone.
KW - bovine growth hormone
KW - growth hormone receptor
KW - homologous hormone-receptor system
KW - radioreceptor assay
KW - somatogenic
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U2 - 10.1016/0303-7207(84)90109-6
DO - 10.1016/0303-7207(84)90109-6
M3 - Article
C2 - 6096183
AN - SCOPUS:0021716753
VL - 38
SP - 109
EP - 116
JO - Molecular and Cellular Endocrinology
JF - Molecular and Cellular Endocrinology
SN - 0303-7207
IS - 2-3
ER -