The use of oestradiol-17β antiserum covalently coupled to Sepharose to extract oestradiol-17β from biological fluids

Glencross, R.G.; Abeywardene, S.A.; Corney, S.J.; Morris, Holly S.

doi:10.1016/s0378-4347(00)80085-7

Cited by 47 publications

(6 citation statements)

References 2 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Plasma oestradiol-17ß was assayed after extrac¬ tion on Sepharose-coupled antibody (Glencross, Abeywardene, Corney & Morris, 1981a) by the radioimmunoassay of Glencross & Pope (1981). Within-and between-assay coefficients of variation in this study, determined from triplicate estimates of three quality control samples of 0, 3 and 6pg oestradiol-17ß/ml water in 12 assays, were 13-2 and 14-0% respectively.…”

Section: Steroid Analysismentioning

confidence: 69%

Effect of pulsatile infusion of gonadotrophin-releasing hormone on plasma oestradiol-17β concentrations and follicular development during naturally and artificially maintained high levels of plasma progesterone in heifers

Glencross¹

1987

Journal of Endocrinology

View full text Add to dashboard Cite

To stimulate a follicular-phase pattern of pulsatile LH release, gonadotrophin-releasing hormone (GnRH; 5 micrograms) was infused (i.v.) hourly into heifers for periods of 5-11 days during the luteal phase of the oestrous cycle, and also when plasma progesterone levels were increased artificially by means of a progesterone-releasing intravaginal device. Plasma oestradiol-17 beta concentrations increased from basal (less than or equal to 2.5 pmol/l) to preovulatory peak levels (20-30 pmol/l) during the first 3 days of GnRH treatment. They were maintained at these values before returning to basal levels within 24 h of cessation of infusion. This response occurred regardless of the source of progesterone (endogenous or administered). Follicular development was observed by ovarian palpation (per rectum) in some heifers at the time of maximum secretion of oestradiol-17 beta. There was no detectable cervical mucus secretion or oestrous behaviour during these periods of high oestradiol-17 beta levels and ovulation did not occur. Treatment with GnRH did not affect plasma progesterone concentrations or oestrous cycle length. The study shows that oestradiol-17 beta secretion and follicular development (and the accompanying oestrus and ovulation) are suppressed during the luteal phase of the cycle by high concentrations of plasma progesterone, and provides strong indirect evidence that such inhibition is associated with a reduction in the pulse frequency of LH release.

show abstract

Section: Steroid Analysismentioning

confidence: 69%

Effect of pulsatile infusion of gonadotrophin-releasing hormone on plasma oestradiol-17β concentrations and follicular development during naturally and artificially maintained high levels of plasma progesterone in heifers

Glencross¹

1987

Journal of Endocrinology

View full text Add to dashboard Cite

show abstract

“…The coefficient of variation and sensitivity of the assay were 6.3% and 1.1 nmol/l respectively. The estradiol assay used the antiserum described by Glencross et al (8) and had coefficient of variation and sensitivity of 11.3% and 7.5 pmol/1 respectively. Both immunoassays were carried out on dried diethyl-ether extracts of plasma.…”

Section: Radioimmunoassaysmentioning

confidence: 99%

A re-evaluation of the anabolic effect of testosterone in rats: interactions with gonadectomy, adrenalectomy and hypophysectomy

Woodward

1993

Acta Endocrinologica

View full text Add to dashboard Cite

Woodward CJH. A re-evaluation of the anabolic effect of testosterone in rats: interactions with gonadectomy, adrenalectomy and hypophysectomy. Acta Endocrinol 1993;128:473-7. ISSN 0001-5598 Growth and body composition were determined in rats implanted with silastic tubes containing testosterone. The implant (i) had no effect on growth in intact males, (ii) restored the sub-normal weight gain of gonadectomized males to normal (+ 30%; p<0.01), (iii) substantially increased weight gain in intact females (+ 172%; p<0.001), and (iv) caused a further increase (+32%; p<0.01) in the accelerated weight gain resulting from ovariectomy. In intact animals of both sexes, testosterone caused significant atrophy of the reproductive tissues; this was accompanied in females by reduced plasma estradiol concentrations. Thus the large effect of testosterone on growth in intact females is probably due to diminished secretion of ovarian estradiol, and is distinct from the smaller effect observed in castrated animals of both sexes. To investigate the mechanism underlying the latter response, testosterone was implanted in rats which had been both adrenalectomized and gonadectomized, and also in hypophysectomized animals. In each case a significant anabolic effect was observed, showing that the response requires neither adrenal nor pituitary glands. In all experiments, increased body weights resulting from testosterone treatment consisted at least partly of fat-free mass. CJH Woodward, It is widely assumed that testosterone has an anabolic effect, meaning that it increases body weight and muscle mass (1). For the rat, however, the underlying experi¬ mental evidence is to some extent equivocal (2). Much work has focused on changes in the levator ani muscle, although this tissue is part of the male reproductive system, and is morphologically dissimilar from skeletal muscle (3). In intact adult male rats, most studies have failed to show any increase in overall body weight after testosterone treatment (e.g. 4). In castrate males and in intact female rats there is more general agreement that androgen treatment increases weight gain (4-6).In the present experiments, it was considered that hormone implants might result in more stable plasma testosterone levels than the injected hormone used in previous studies. Accordingly, growth, body composi¬ tion and plasma steroid concentrations have been monitored in intact and gonadectomized rats with or without hormone implants. The effects of adrenalectomy and hypophysectomy have also been studied. Materials and methods AnimalsExperiments were carried out under the Animals (Scien¬ tific Procedures) Act 1986 of the UK. Wistar rats were given chow diet ad libitum. Water was also given ad libitum, except to adrenalectomized (ADX) rats, which received NaCl solution (0.15 mol/1). Weight gain was followed for at least one week before implantation, and the animals divided into groups of similar pre-operative weight and growth rate. Testosterone implants were made by a method adapted from Pirke and Spyra (...

show abstract

“…Oestradiol-17 p concentrations were measured using 4 ml plasma by the method of Glencross and Pope (1981) with the modified extraction procedure of Glencross, Abeywardene, Corney and Morris (1981). Oestradiol-17 p concentrations were measured using 4 ml plasma by the method of Glencross and Pope (1981) with the modified extraction procedure of Glencross, Abeywardene, Corney and Morris (1981).…”

Section: Hormone Radioimmunoassaysmentioning

confidence: 99%

Pituitary responses of seasonally anoestrous ewes to long-term continuous infusion of low doses of GnRH

et al. 1989

View full text Add to dashboard Cite

The response to long-term continuous infusion of gonadotrophin releasing hormone (GnRH) was monitored in progesterone-treated seasonally anoestrous ewes. Using osmotic pumps, groups of five ewes each received 0 (controls), 125, 250, 500 or 1000 ng GnRH per h subcutaneously for a period of 21 days. Blood samples were collected at 30-min intervals from 6 h before until 24 h after the start of treatment and then for 8-h periods on days 2, 8, 15 and 21. After 21 days of treatment all the ewes were slaughtered to determine pituitary GnRH receptor numbers. Continuous infusion of GnRH resulted in a short-lived (2 day) increase in plasma LH and oestradiol concentrations after which they were not different from the pre-treatment values. Over the later period of treatment when the pituitary gland was not responding to the exogenous GnRH (days 8, 15 and 21), LH episodes (presumably due to endogenous GnRH secretion from the hypothalamus) were observed. Continuous infusion of GnRH was also associated with a suppression in plasma FSH concentrations, the duration of which was dosedependent. Only at the highest GnRH dose level (1000 ng/h) was there a significant reduction in pituitary GnRH receptor content.

show abstract

The use of oestradiol-17β antiserum covalently coupled to Sepharose to extract oestradiol-17β from biological fluids

Cited by 47 publications

References 2 publications

Effect of pulsatile infusion of gonadotrophin-releasing hormone on plasma oestradiol-17β concentrations and follicular development during naturally and artificially maintained high levels of plasma progesterone in heifers

Effect of pulsatile infusion of gonadotrophin-releasing hormone on plasma oestradiol-17β concentrations and follicular development during naturally and artificially maintained high levels of plasma progesterone in heifers

A re-evaluation of the anabolic effect of testosterone in rats: interactions with gonadectomy, adrenalectomy and hypophysectomy

Pituitary responses of seasonally anoestrous ewes to long-term continuous infusion of low doses of GnRH

Contact Info

Product

Resources

About