TY - JOUR
T1 - Short loop feedback control of luteinizing hormone in the rabbit
AU - Molitch, M.
AU - Edmonds, M.
AU - Jones, E. E.
AU - Odell, W. D.
PY - 1976/1/1
Y1 - 1976/1/1
N2 - A radioimmunoassay for rabbit luteinizing hormone (rLH) in which rLH shows no significant cross reaction with human LH (hLH) or human chorionic gonadotropin (hCG) was employed to test for the existence of a short loop feedback for LH in the rabbit. 2 Wk after castration, hCG and hLH were administered intravenously to rabbits, and the effects on circulating rLH were measured. Purified hLH (10 ng or 100 IU) produced significant depression of blood rLH within 30 to 60 min of intravenous injection. Saline administered to the same animals produced no changes in rLH. Injection of hCG (2,000 IU) under the same conditions also produced a significant fall in rLH. However, hCG administered to rabbits castrated 6 wk prior to study failed to suppress endogenous rLH. These data demonstrate, by direct radioimmunoassay quantification of blood hormones, the existence of a short loop negative feedback for LH in the rabbit. They also suggest that the sensitivity of the short loop changes with time after castration.
AB - A radioimmunoassay for rabbit luteinizing hormone (rLH) in which rLH shows no significant cross reaction with human LH (hLH) or human chorionic gonadotropin (hCG) was employed to test for the existence of a short loop feedback for LH in the rabbit. 2 Wk after castration, hCG and hLH were administered intravenously to rabbits, and the effects on circulating rLH were measured. Purified hLH (10 ng or 100 IU) produced significant depression of blood rLH within 30 to 60 min of intravenous injection. Saline administered to the same animals produced no changes in rLH. Injection of hCG (2,000 IU) under the same conditions also produced a significant fall in rLH. However, hCG administered to rabbits castrated 6 wk prior to study failed to suppress endogenous rLH. These data demonstrate, by direct radioimmunoassay quantification of blood hormones, the existence of a short loop negative feedback for LH in the rabbit. They also suggest that the sensitivity of the short loop changes with time after castration.
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U2 - 10.1152/ajplegacy.1976.230.4.907
DO - 10.1152/ajplegacy.1976.230.4.907
M3 - Article
C2 - 1267022
AN - SCOPUS:0017187815
SN - 0002-9513
VL - 230
SP - 907
EP - 910
JO - American Journal of Physiology
JF - American Journal of Physiology
IS - 4
ER -