Low estrogen oral contraceptives and the hypothalamo-pituitary axis

The hypothalamo-pituitary axis in a group of 10 women (17-25 years of age) taking low-dose-estrogen oral contraceptives (20 micrograms ethinylestradiol (EE) + 150 micrograms desogestrel) for at least 6 months was investigated. The subjects underwent the GnRH (50 micrograms) and TRH (200 micrograms) stimulation tests for the evaluation of LH, FSH, Pr1, TSH and GH secretion. In the basal blood sample, E2, P, free T, A and SHBG levels were also determined. An elevation in LH response to GnRH was found, whereas FSH was inhibited. After TRH administration, the Pr1 response was the same in the oral contraceptive cycle as in the pretreatment cycle. Similar results were observed after TSH. Significantly, GH responded to TRH stimulation in the oral contraceptive cycles, but not in the pretreatment cycles. These results show that the new combination of 20 micrograms EE and desogestrel blocks hypothalamic production of GnRH. The different response to GnRH of LH and FSH reveals a differentiated sensitivity to the oral contraceptive which seems to inhibit the pituitary FSH-secreting gonadotrope cells in particular.

[Correlation between presence of estradiol receptors and epidemiological and clinical data on breast cancer]

The aim of the study is to find an eventual correlation between the presence of Er receptors and epidemiologic (age, domestic anamnesis, weight, menarca) and clinicist factors (cancerous diameter, linfonodes, first symptoms). The presence of receptors is very important for the start of endocrine therapy. In conclusion we can affirm the absence of correlation between the presence of receptors and the factors we considered. The only exception is about the age of patients; very probably because too little number of patients was considered. On the contrary a correlation was observed between receptors and severity of cancerous receptors in neoplastic tissues was obtained with Poffanelli method using an Ultra-Turrax homogenization followed by a centrifugation at 3800 rpm; the separation was achieved with carbon-dextran.

[Distribution in a density gradient of human erythrocytes: sex-related differences]

Differences in erythrocyte distribution on Ficoll-Sodium Metrizoate discontinuous density gradient were evaluated between adult males and females. Testosterone and androstenedione plasma levels were tested in males, oestradiol, progesterone and prolactin in both males and females. Female group showed a much higher proportion of lighter younger erythrocytes than males, while males showed higher proportion of denser older cells. Positive correlation was found between young cell percent and oestradiol level, both in males and females, but no correlation was found with androgen hormones.

[Changes in the density gradient distribution of erythrocytes during the menstrual cycle]

Modifications in erythrocyte density distribution were evaluated, by means of centrifugation on Ficoll-Triosil discontinuous density gradient, in five healthy young women during menstrual cycle. Oestradiol and progesterone plasma levels were tested, showing normal and typically ovulatory-like variations during the cycle. Youngest cell populations showed always quantitative increases from the follicular to the ovulatory phase of the cycle, reverting to basal values in the luteal phase. Possible hormonal or haemorrhagic causes are discussed.