Numerous studies have suggested that ovarian hormones are able to modulate insulin sensitivity, but their exact role remains unclear. We have investigated whether different doses of 17beta-oestradiol mediate changes in insulin sensitivity and if these changes could be related to modifications of insulin receptor substrate-1 (IRS-1). Female rats were ovariectomized and later separated into three...

Conventionally reared female BALB/c mice, rendered susceptible to Mycoplasma hominis infection of the genital tract by treatment with oestradiol, have increased numbers of endogenous vaginal bacteria. The latter was reflected by the occurrence of bacterial growth in 95 (65.5%) of 145 cultures undertaken to isolate M. hominis from oestradiol-treated mice, but in only seven (4.8%) of 146 cultures...

Four amenorrhoeic women were treated with a purified sheep fsh preparation. During treatment, plasma progesterone, oestradiol and lh concentrations were measured every 24 or 48 hr. In all the women, an lh peak was found during treatment, even though in three of these there was no evidence of adequate follicular maturation, as assessed by plasma oestradiol levels. These results indicate that a p...

In the previous studies a hypothesis was developed from the results by using trivariate Weibull model that the increase in leptin concentrations during the second half of the menstrual cycle may be related to changes in the steroidal milieu during the pre ovulatory period and the luteal phase. The present study was undertaken to test this hypothesis further by examining the effect of treatment ...

Follicle deviation is characterized by continued growth of the largest (developing dominant) follicle and reduced growth of the smaller (subordinate) follicles. The aim of the present study was to test the following hypotheses: (1). oestradiol contributes to the depression of circulating FSH encompassing follicle deviation and (2). oestradiol plays a role in the initiation of deviation. Heifers...

CURRENT views on the mechanisms of oestrogen action involve specific cytoplasmic protein molecules to which oestrogen becomes bound on entering the cell. Another different receptor protein exists in the cell nucleus and oestradiol must be transferred to this second receptor before it can produce its stimulating effect (Raspe, 1971). The nature of the effect is determined by the characteristics ...

Lipoprotein and steroid hormone levels were measured in 61 bilaterally oophorectomised women who had been treated for 3 years with implants containing either oestradiol alone or oestradiol plus testosterone. The lipoprotein levels associated with each of the two therapy regimens were compared. In addition, lipoproteins were measured in 67 untreated bilaterally oophorectomised age-matched women ...

AIMS Idiopathic and familial forms of pulmonary arterial hypertension (PAH) predominantly affect females through an unknown mechanism. Activity of the serotonin transporter (SERT) may modulate the development of PAH, and mice overexpressing SERT (SERT+ mice) develop PAH and severe hypoxia-induced PAH. In the central nervous system, oestrogens influence activity of the serotonin system. Therefor...

Changes in pulsatile secretion of LH, FSH, oestradiol and progesterone were related to the growth phase, early plateau phase and regression phase of the first ovarian dominant follicle of the oestrous cycle in Bos indicus heifers. Relationships between these hormones during the three phases were also investigated. Accurate measurements of episodic ovarian steroid secretion were obtained by cath...

Both natural oestrogens and progesterone influence synaptic plasticity and neurogenesis within the female hippocampus. However, less is known of the impact of synthetic hormones on hippocampal structure and function. There is some evidence that the administration of the synthetic progestin, medroxyprogesterone acetate (MPA) is not as beneficial as natural progesterone and can attenuate oestroge...