The seasonality of reproductive activity in the ewe in temperate latitudes is controlled by photoperiod. Its annual variations control the temporal organization of the sexual cycle by changing the activity of the gonadotrophic axis. Cyclic oestrous behaviour usually appears in the ewe at the end of summer or the beginning of autumn and finishes in winter or at the very beginning of spring. Seas...

In 1961 Andr#{233}nand Borglin suggested that congenital dislocation of the hip could be the consequence ofabnormal oestrogen metabolism in the perinatal period. They studied oestrogen excretion in eleven newborn infants with dislocated hips and twenty-six control infants during the first three days of life. They found elevated levels of oestrone and oestradiol in the patients with dislocation....

The objective of the present study was to determine the effects of soya and whey milk protein, α-lactalbumin (α-LA), on mammary gland morphology and the structural support of the gland, in pre-pubertal mice after 7 d of treatment. In Expt 1, weaned (day 21) CD1 mice were given one of the four treatments, three included dietary supplements: (1) control diet, casein, (2) soya, (3) α-LA and (4) su...

17 beta-Oestradiol (ED when subscript to K) and the phytoestrogen isoflavone genistein (GEN) inhibit glucose transport in human erythrocytes and erythrocyte ghosts. The selective oestrogen receptor modulators or anti-oestrogens, faslodex (ICI 182780) (FAS) and tamoxifen (TAM), competitively antagonize oestradiol inhibition of glucose exit from erythrocytes (K(i(ED/FAS))=2.84+/-0.16 microM and K...

That oestradiol can have both negative- and positive-feedback actions upon the release of gonadotrophin-releasing hormone (GnRH) has been understood for decades. The vast majority of studies have investigated the effects of in vivo oestrogen administration. In the past decade, evidence has accumulated in many neuronal and non-neuronal systems indicating that, in addition to traditional genomic ...

hormone. This possibility has been examined by preparing informofers [nuclear ribonucleoprotein particles containing DNA-like RNA (Samarina el al., 1968)] from isolated uterine nuclei. When immature rats are treated with oestradiol-178 for 1 4 h , and the uterine RNA labelled with uridine during a subsequent incubation in vitro, the synthesis of RNA in informofers is stimulated severalfold. We ...

The phase of the menstrual cycle in women who had attempted suicide was determined by structured interview. 108 young women were investigated within 24 h of the attempt. Patients were grouped according to menstrual week and whether they used oral contraception (OC) (n = 73) or not (n = 35). In OC non-users suicide attempts were associated with low plasma oestradiol: they tended to happen during...

Mast cell populations in the vaginal cul-de-sac of female brushtail possums do not appear to be related to microbial invasion but changes in their density occur at oestrus, indicating a hormonal influence. The present study examined the effect of treatment with oestradiol on microflora and on mast cell numbers and their spatial location in cul-de-sac tissue of seasonally anoestrous brushtail po...

Implants ofprogesterone on the day ofdioestrus II in the hamster induced on the following day an increase in circulating levels of progesterone (6\m=.\0\m=+-\0\m=.\7ng/ml, N = 8; sesame oil controls, <0.5 ng/ml, N = 6) and a decline in serum levels of LH (5\m=.\3\m=+-\0\m=.\4ng/ml; controls 12 \m=+-\2 ng/ml) and oestradiol (10 \m=+-\2 pg/ml ; controls 69 \m=+-\5 pg/ml). The production of andros...