Formation and metabolism of steroids in the fetus and placenta

Cortisol in human tissues at different stages of life

Aim of the work was to measure the cortisol level in human tissues at different stages of life, by means of radioimmunoassay and by chromatography. Viable samples of 13 different tissues were obtained during surgical intervention from 30 to 70 years old patients of either sex. Mean tissue cortisol concentration was 78 +/- 35 ng/g, ranging from 20 +/- 10 ng/g in the thyroid to 124 +/- 76 ng/g in the kidney. Similar values were measured in the corresponding tissues from not decayed corpses, so that paired values could be mediated. However the pancreas, and corrupted autopsy tissues, gave nil or exceedingly high cortisol concentration values; in some cases, opposite extreme values were measured in different organs of the same body. Cortisol concentration was also measured in 11 sound different tissues of spontaneously aborted or stillbirth fetuses, between 16 and 36 weeks of gestation. Mean value was 63 +/- 27 ng/g, ranging from 30 +/- 25 ng/g in the liver to 104 +/- 52 ng/g in the lungs. Also in fetuses nil or exceedingly high cortisol values occurred in altered tissues. One hundred and fourteen samples of limbs and carcasses of 7 to 12 gestational weeks embryos, obtained from voluntary abortions, were also examined: 20% gave nil result, in the remaining mean cortisol concentration was 32 ng/g. In 33 samples of embryos' mixed viscera, RIA and chromatography gave unreliable exceedingly high values. The nil and the exceedingly high values measured in the altered autoptic tissue specimens were inconsistent with the cortisol blood level measured in the patients, as were those measured in embryonic tissues with the acknowledged blood and adrenals cortisol levels at that stage of life. Thus cortisol may be measured by RIA and by chromatography in sound tissues, while the values obtained in the pancreas, in corrupted tissues, and in embryonal viscera do not represent the hormonal milieu, but are likely artifacts due to impeachment of the diagnostic system.

Effects of melanotropic peptides on fetal adrenal gland

Adrenal glands from early, mid, and late fetuses of rabbit, guinea pig, and rat, and from newborn animals of each species, were incubated for 1-4 h with and without 0.1 nM-1 microM ACTH, alpha- or beta-melanocyte-stimulating hormone (alpha MSH or beta MSH). The effects of the peptides were measured on production of glucocorticoids, and on incorporation of labeled thymidine or leucine into DNA or protein, respectively. The findings were similar in all three species. ACTH stimulated synthesis of glucocorticoids throughout fetal life. Potency increased progressively, as reflected by declining minimal effective dose and rising maximal response. In early and mid fetus alpha MSH and beta MSH caused a modest glucocorticoid steroidogenic effect. ACTH and alpha MSH stimulated DNA and protein synthesis in the early and mid fetal gland. alpha MSH was more potent than ACTH in these respects, minimal effective dose being generally 10 times less and maximal response 25-200% greater. The effects diminished or disappeared in the late fetal and newborn gland. These data indicate that alpha- and beta MSH possess steroidogenic or growth-promoting properties, or both, for the fetal adrenal gland.

Steroids in the assessment of prenatal development

Methods for identifying the fetus at risk and monitoring fetal well-being as pregnancy progresses are now an established part of prenatal care in the Western World. In this short review the use of steroids in the assessment of prenatal development is discussed. The metabolism of oestrogens, progestogens, corticosteroids and androgens during pregnancy is outlined and the relative merits, in terms of usefulness and practicability, of urinary and plasma steroid assays are discussed.