A specific radioimmunoassay technique was used to measure the concentration of oestradiol at weekly intervals in the blood plasma of seven pullets from 7 weeks of age until they were sexually mature. Large differences in oestradiol concentration were observed between birds. The mean concentration was 94 pg/ml plasma 7 weeks before the first egg was laid. The concentration then began to rise sha...

Concentrations of oestradiol-17 beta and oestrone were measured in the uterine arterial and venous blood of anaesthetized sows on Days 11, 13 or 15 of the oestrous cycle or of pregnancy. Uterine arterial blood flow and the amounts of oestradiol-17 beta and oestrone in uterine flushings were determined in the same animals. In pregnant animals arterial and venous concentrations were significantly...

The biochemical validity of published labelled-ligand and ligand-antibody methods for the histological localisation of oestrogen receptors (ER) in breast carcinomas was assessed by measuring specific and non-specific binding of 3H-oestradiol to pretreated MCF-7 monolayers; the monolayers had been either frozen and thawed, then air-dried or acetone-fixed, or fixed in formaldehyde to reproduce th...

Climacteric symptoms in 120 women were treated with a total of 469 hormone implants (oestradiol 50 mg and testosterone 100 mg) over a period of four years. All patients with a uterus were given an oral progestogen to prevent endometrial hyperplasia. There was a marked response to treatment, hot flushes being improved in all patients, depression in 99% and loss of libido in 92%. Patient acceptab...

Oestradiol enhances pituitary sensitivity to gonadotrophin-releasing hormone (GnRH) in normal women, while in women undergoing ovulation induction the putative factor gonadotrophin surge attenuating factor (GnSAF) attenuates the response of luteinizing hormone (LH) to GnRH. To study the relationships between oestradiol and GnSAF during ovulation induction, 15 normally ovulating women were inves...

The Iberian Lynx Ex-Situ Conservation Programme is an essential part of a co-ordinated action plan to conserve the most endangered felid species of the world. Successful captive breeding demands reliable methods for reproduction monitoring including reliable non-invasive pregnancy diagnosis. During a 3-year study, urine samples from six captive Iberian lynx females were obtained (one non-pregna...

OBJECTIVE Oestrogen expression may indicate a difference in resistance potential to mechanical strain. The purpose of this study was to investigate the expression of oestrogen and oestrogen receptors in mandibular condylar cartilages in male and female Sprague-Dawley rats at different ages. MATERIALS AND METHODS One-hundred SD rats at the age of 2, 4, 8 weeks and 4, 12 months in both sexes, 1...

Nine Friesian dairy cows were treated with 2.5 micrograms GnRH i.v. at 2-h intervals for 48 h commencing between Days 3 and 8 post partum. Hormone concentrations were measured in jugular venous plasma. An episodic pattern of LH release was induced in all animals and there was no significant change in amplitude during treatment. However, cows treated between Days 7 and 8 ('late') showed higher L...

Increasing evidence shows that sex hormones exert a protective effect on the vasculature, especially in the regulation of the active vasomotor responses. However, whether sex hormones affect vascular remodelling is currently unclear. In the present study, we tested the hypothesis that testosterone in males and β-oestradiol in females prevent inward remodelling, possibly through inhibition of cr...

Heifers were treated with saline (Group I, N = 10), keyhole limpet haemocyanin (KLH; Group II, N = 10), androstenedione-KLH antigen (Group III, N = 14), or oestradiol-17 beta-KLH antigen (Group IV, N = 14). Booster injections were given to produce binding of greater than 10% at dilutions of 1:100 to 1:1000 (50% binding = 14 X 4 pg androstenedione and 9 X 5 pg oestradiol). The heifers were mated...