Estrone and estradiol concentrations in peripheral plasma of laying hens as determined by radioimmunoassay

Abstract

An application of radioimmunoassay to measurement of concentrations of estradiol and estrone in peripheral plasma of hens is described. Evidence is presented that the estradiol measured by the procedure was essentially estradiol-17β.For 13 ovulatory cycles the average concentration of estradiol was 123 pg/ml with a range from 36 pg/ml to 284 pg/ml. The corresponding average concentration for estrone was 64 pg/ml with a range from 14 pg/ml to 138 pg/ml. For 12 days of no ovulation the average concentration of estradiol was 142 pg/ml with a range from 42 pg/ml to 364 pg/ml. The corresponding average value for estrone was 91 pg/ml with a range from 18 pg/ml to 242 pg/ml.The results are interpreted as demonstrating the existence of peak levels of plasma estradiol at 22–18 h and again at 6–2 h before ovulation, and a minimal level at 14–10 h before ovulation. The corresponding plasma estrone concentrations displayed a similar cycle but the earlier peak and the minimum occurred 2–4 h later than the corresponding values for estradiol. Such peak values were not demonstrable on days when ovulation did not occur.The results are discussed briefly in relation to variation in the levels of blood progesterone during the ovulatory cycle.

Plasma hormone levels in the cow

“…No bottle lasted more than 5 days and there was no detectable blank during this time. The phospho-buffered saline solution and the dextran-coated charcoal suspension were identical to those used previously (Peterson & Common 1972).…”

“…Details of this radioimmunoassay (RIA) procedure have been reported previously (Peterson & Common 1972). Plasma (2 ml) was extracted 18: 123-9 in duplicate with 7 ml diethyl ether.…”

A Preliminary Assessment of the Source of Oestrogen Within the Ovary of the Domestic Fowl, Gallus Domesticus

“…A similar rôle for oestrogens in the hen has not been fully investigated. During the ovulatory cycle of the hen, maximum concentra¬ tions of oestrone and oestradiol are known to occur in peripheral plasma 4 to 6 hr before ovulation (Peterson & Common, 1972;Senior, 1974a) and the increase in the concentration of oestradiol precedes that of LH by 2 hr (Senior & Cunningham, 1974 …”

Oestrogens in Bovine Fetal and Maternal Plasma Near Term

“…The plasma was extracted with 10 vols redistilled diethyl ether and chromatographed on micro-columns of Sephadex (Wu & Lundy, 1971). The oestrone and oestradiol fractions thus separated were subjected to radioimmunoassay by the method of Peterson & Common (1972), using antisera against oestradiol-17ß-17-BSA and oestradiol-17/J-6-rBSA, respectively. Oestrone cross-reacted 56% with the oestradiol-17ß-17-BSA antiserum and oestradiol-17a cross-reacted 1-9% with the antiserum against oestradiol-17/Í-6-BSA.…”