Open AccessOestradiol-17β and prolactin levels in rat peripheral plasma
Author(s) -
R. A. Hawkins,
B. Freedman,
A.D. Marshall,
E. Killen
Publication year - 1975
Publication title -
british journal of cancer
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.833
H-Index - 236
eISSN - 1532-1827
pISSN - 0007-0920
DOI - 10.1038/bjc.1975.147
Subject(s) - prolactin , endocrinology , medicine , estrous cycle , radioimmunoassay , ovariectomized rat , hormone , chemistry , biology
Radioimmunoassay methods for the determination of oestradiol-17 beta and prolactin have been examined for their reliability and applied to the measurement of hormone concentrations in the plasmas from male and female rats. Prolactin was detectable in all samples (greater than 7 ng RP-1 ng/ml) but the concentration of oestradiol-17 beta was below the sensitivity of the method (greater than 0-10 ng/100 ml) in ovariectomized females. Plasma oestradiol-17 beta concentration rose gradually from metoestrus to proestrus and fell to barely detectable levels in oestrus. Plasma prolactin concentration was very variable even for rats in the same stage of the oestrous cycle but values were minimal in the afternoon of diestrus and a surge in secretion occurred in the afternoon of proestrus. In addition to the stage of the oestrous cycle, the prolactin concentration was influenced by mode of blood collection, degree of haemolysis and choice of serum or plasma. There was no correlation between the concentration of prolactin and that of oestradiol-17 beta in the same sample of plasma.