Enzyme-linked immunosorbent assay of pS2 in breast cancers, benign tumors, and normal breast tissues. Correlation with prognosis and adjuvant hormone therapy.

An enzyme-linked immunosorbent assay using monoclonal and polyclonal antibodies against recombinant pS2 was devised. It was used to measure pS2 concentration in the cytosol of 339 breast cancer, 15 fibroadenomas, 16 cases of benign breast disease, and 6 normal breast tissues. The mean value of pS2 concentration was higher in cancer, but the protein could be detected readily in benign tumors and even in normal breast. The concentration of pS2 was significantly lower in postmenopausal women and tumors of differentiation Grade 3. The pS2 concentration was correlated strongly with the presence of estrogen receptors (ER) and progesterone receptors (PR). No correlation was observed with the size, histologic type of the tumor, and lymph node status. The prognostic value of pS2 appeared relatively limited. It was clear cut only for a relatively small group of patients (approximately 15%), who had low concentrations of pS2 (less than or equal to 0.32 ng/mg of protein). These patients had a shorter disease-free interval and overall survival time. The most striking correlation was observed with the outcome of adjuvant hormone therapy. pS2 concentration was shown to be the most potent prognostic factor, preceding even ER.

Effects of counterregulatory hormones on insulin-induced glucose utilization by individual tissues in rats.

The effect of counterregulatory hormones (epinephrine, norepinephrine and glucocorticoids) on insulin-induced glucose utilization in individual tissues of normal rats was investigated in vivo. This was done in normoglycaemic conditions, using the euglycaemic hyperinsulinaemic clamp combined with an injection of 2-[1-3H]-deoxyglucose. The main effect of these hormones was to reduce insulin-induced glucose utilization in skeletal muscles and particularly in the oxidative one. No changes were observed in heart diaphragm and adipose tissues. These results emphazise the role of counterregulatory hormones on glucose utilization and demonstrate that muscles are their major site of action. They support the notion that the increase in plasma concentrations of these hormones could play a role in states of insulin resistance like obesity and diabetes.

Synthesis of 7 alpha- and beta-carboxymethyl derivatives of cortisol, corticosterone, deoxycorticosterone and cortisone. Immunogenic properties of cortisol, corticosterone and deoxycorticosterone derivatives.

7 alpha- and 7 beta-Carboxymethylderivatives of cortisol, corticosterone and deoxycorticosterone have been synthetized. After coupling to bovine serum albumin, they were used to elicit antibodies in rabbits. Highly specific antisera were obtained which may possibly be used for a direct radioimmunoassay of these steroids in human and rodent plasma. In the case of the derivatives of cortisol and corticosterone and stereoisomery of the coupling had an effect on the affinity and the specificity of the antisera. In all immunized rabbits the antisera obtained with the 7 alpha-derivative had a higher affinity and a narrower specificity than the antiserum obtained with the 7 beta-derivative.

Effects of long-term grouping on serum cortisol levels in Microcebus murinus (Prosimii).

The influence of social interactions on plasma cortisol was studied in captive Microcebus murinus, a prosimian primate. Regardless the group composition, there is an annual variation in cortisol levels characterized by an autumn peak that coincides with the fattening and sexual resting period. The beginning of activity, early in January, is accompanied by a fall in cortisol levels. Cortisol levels are higher in females than in males both in pairs and in heterosexual groups. In paired animals, mean cortisol levels vary around 140 ng/ml in males and 230 ng/ml in females. In all grouped animals, a persistent adrenocortical activation was found and represents a 75 to 120% increase compared to paired animals. Due to the fact that M. murinus, the mouse lemur, is a solitary species with a primitive social structure, the high concentrations of cortisol found in grouped mouse lemurs could be a reaction to persistent social stress. Such high concentrations of cortisol may be related to poor reproductive success of grouped females and could play a major part in the pathological lesions found in males that die while maintained in social groups.

Sexual inhibition in a prosimian primate: a pheromone-like effect.

The effect of dominant urine odour on plasma levels of testosterone and cortisol was studied in the prosimian primate Microcebus murinus. This species shows a photoperiod-dependent cycle of sexual activity. In particular, mean testosterone levels vary from 15 nmol/l during the annual rest period to 245 nmol/l during the breeding season. When males of this solitary and territorial species are artificially grouped in captivity, they develop a social hierarchy which in turn results in physiological disorders, especially of reproductive function, in non-dominant individuals. Since olfactory behaviours appear to be important in the establishment and maintenance of the social structure, we have tested the effects of dominant odorant signals upon the sexual inhibition observed in male conspecifics. A preliminary experiment showed that a decrease in plasma testosterone concentrations could be induced by dominant scent marks. Furthermore, dominant urine odour alone was found to be sufficient to induce this modification. Plasma cortisol levels also increased in these animals. Conversely, when sexually inhibited males were olfactorily isolated from dominant urine odour, testosterone and cortisol concentrations returned to a normal seasonal level. These effects were observed even in males which had had no previous contact with the dominant urine donor. It is inferred from these results that a pheromone-like process could lead to sexual inhibition in male Microcebus murinus exposed to an odorant urinary signal produced by a dominant individual. Nevertheless, the endocrine response seems to vary according to the seasonal period of the sexual activity cycle which suggests that the social effect described is modulated by other external (e.g. photoperiodic) or internal (e.g. reproductive physiology) factors.

Protein binding of cortisol in human cerebrospinal fluid.

A method devised previously to precisely measure the concentration of unbound cortisol was used to compare plasma and cerebrospinal fluid (CSF) in 34 patients. In CSF the percentage of free cortisol was 88.4 +/- 6.3% (mean +/- SD). Its concentration was 4.94 +/- 2.00 ng/ml, only one third of the concentration of unbound cortisol in plasma of the same patients (14.3 +/- 8.8 ng/ml). Total and unbound cortisol in CSF were correlated with unbound cortisol in plasma; however, this correlation was rather loose (r = 0.527 and 0.554, respectively) due to large individual variations. Moreover, at high concentrations of unbound cortisol in plasma, the ratio of total cortisol in CSF/unbound cortisol in plasma was decreased. Thus, it is impossible to simply consider cortisol in CSF as a dialyzate of cortisol in plasma. The binding of cortisol in CSF was due to a protein having the electrophoretic mobility in polyacrylamide gels of plasma corticosteroid-binding globulin (CBG), and displaying the same hormonal specificity. The concentration of this protein was measured in 16 individual patients. This concentration, when expressed per protein content, was about two thirds of that of plasma CBG, and this ratio was extremely variable in individual patients. Individual variations of cortisol-binding globulin in CSF could not be attributed to variations of CBG in plasma nor to variations of protein content in CSF. There was an inverse relationship (r = 0.888) between unbound cortisol in CSF and the concentration of cortisol-binding globulin in this fluid, showing that CBG exerts a physiological role in CSF.

[Pituitary agenesis in the rat: synthesis of testosterone in fatal testes]. / Agénésie hypophysaire chez le rat: synthese de testostérone dans les testicules foetaux.

Testosterone radioimmunological assays were made in testes of 19th day fetuses affected with pituitary agenesis. Testosterone was found very reduced but still present, indicating a basic synthesis, independent of hypophyseal stimulation. General apparatus of affected fetuses is grossly normal. Intervention of chorionic gonadotrophin is hypothesized.

7 alpha- and 7 beta-carboxymethyl-derivatives of 17-hydroxyprogesterone and 11-deoxycortisol. Synthesis and immunogenic properties.

7 alpha- and 7 beta-carboxymethyl-derivatives of 17-hydroxyprogesterone and 11-deoxycortisol have been synthesized. After coupling to bovine serum albumin, they were used to elicit antibodies in rabbits. No major difference in the steroid specificity of the antisera was observed when either 7 alpha- or 7 beta-epimers were used for immunization. In both cases, highly specific antisera were obtained which may possibly be used to assay human plasma 17-hydroxyprogesterone and 11-deoxycortisol without chromatographic purification.

Plasma testosterone and the diagnosis of panhypopituitarism in women.

Plasma testosterone was shown to be a very sensitive index of panhypopituitarism in women. In 18 women, testosterone levels were found to be 0.06 +/- 0.04 ng/ml (mean +/- SD; normal, 0.40 +/- 0.10 ng/ml). In all patients, the values were below 2 SD of testosterone levels found in normal women. Dihydrotestosterone concentrations were similarly modified. Such an important decrease in plasma testosterone was probably due to the additional effect produced by the functional suppression of both sources of testosterone precursors: the adrenals and the ovaries.

Assay of unbound cortisol in plasma.

A method for measuring the unbound fraction of plasma cortisol which is suitable for clinical use is described. It is shown that unless some precise experimental conditions are fulfilled, important errors may result when determining the unbound fraction of the hormone. The assay is practical (2 ml of plasma are necessary) and reproducible (coefficient of variation: 2.7% within the same assay and 3.1% in different assays). Unbound cortisol measured at 0800 h in 86 healthy individuals was 9.7 +/- 2.6% (SD) of total cortisol and 15.0 +/- 8.5 ng/ml of plasma (temperature: 37 C). No significant difference was found between men and women or according to age. In most cases, variations of unbound plasma cortisol were more important than the variations of total plasma cortisol. This explains why unbound cortisol was a better discriminator in some pathological conditions. In Cushing's syndrome unbound cortisol was found to be increased on the average 2.9 fold whereas total cortisol was only increased by 53%. Unbound cortisol was especially high (24.7 +/- 3.8% of total cortisol and 78 +/- 18.5 ng/ml of plasma) in Cushing's syndrome due to adrenal carcinoma. In adrenal insufficiency, unbound cortisol averaged 6% of total cortisol and 1.4 ng/ml of plasma.

Hormonal and metabolic effects of somatostatin in diabetic patients submitted to an i.v. arginine infusion.

Hormonal and metabolic effects of a synthetic linear somatostatin were tested in insulin-dependent subjects submitted to an intravenous arginine infusion. Arginine alone induced a rise in plasma growth hormone (HGH) and glucagon (IRG) concentrations but did not affect the spontaneous diurnal decrease of plasma cortisol; blood glucose concentration rose while that of alanine decreased suggesting enhanced gluconeogenesis; concentrations of plasma free fatty acids (FFA) and 3-hydroxybutyrate decreased. Somatostatin, at three different dosages, markedly influenced these patterns: HGH response to arginine was suppressed by the lowest somatostatin dose; IRG response was progressively inhibited by increasing doses of somatostatin but never reached zero; cortisol level was not decreased but slightly increased by somatostatin. Substrate responses to arginine were also modified by somatostatin: alanine disappearance was impaired, this effect being dose-related; plasma FFA and 3-hydroxybutyrate concentrations showed a significant increase rather than decrease, consistent with somatostatin suppression of residual insulin secretion. Tolerance to somatostatin was good and no alteration of hemostasis was observed.

Fetal breathing and adaptation to maternal hemorrhage in the sheep.

The effect of maternal hemorrhage in chronic preparations was studied on fetal lambs in the last month of gestation. Fourteen to 20 per cent of maternal blood was estimated to have been removed within 30 minutes, which resulted in a drop of 30 per cent of mean maternal arterial pressure. A fetal bradycardia started 28 +/- 13 minutes after the beginning of maternal hemorrhage. It lasted 30 +/- 15 minutes and was concomitant with a rise in fetal arterial pressure. It was followed by a long-lasting fetal tachycardia of 130 +/- 38 minutes and was corrected only by reinfusion of blood to the mother. The fetal blood gases demonstrated a mild asphyxia with a persistent metabolic acidemia until reinfusion of blood to the mother. Maternal and fetal plasma cortisol levels rose significantly at the end of the hemorrhage. Tracheal fluid flow did not change. Fetal breathing recorded 20 hours before and 24 hours after the experiment did not show consistent changes, but during fetal bradycardia there was no fetal breathing. Recent clinical investigations in this field have been made in the human fetus to estimate standards of fetal well being. These peculiar animal experiments do not show any significant improvement by recording fetal breathing over the recording of prelabor fetal heart rate.