Daniel R. Aquilano

Failure of the Müllerian regression factor in two patients with complete androgen insensitivity syndrome

SummaryThe present paper describes the histological and endocrinologic features of 2 subjects with 46,XY karyotype affected by complete androgen insensitivity syndrome (AIS) with müllerian structures. Both patients had fallopian tubes, but only one had also uterus and presented a seminoma. Serum levels of luteinizing hormone, testosterone and estradiol were high or in the upper part of normal limits, whereas levels of follicle-stimulating hormone were normal. The association between AIS and the presence of müllerian structures observed in these 2 patients might be explained by an impaired synthesis of müllerian regression factor or by a failure in its mechanism of action.

Determination of serum estriol levels using a125I-radioimmunoassay

SummaryA new method of radioimmunoassay (RIA) for serum estriol (E3) which utilizes125I-estriol as a tracer has been developed. This steroid was radioiodinated with chloramine T and purified by Sephadex LH-20 column chromatography. Two hundred and sixty-two samples from 130 normal pregnant patients at different stages of gestation were analysed. From 5 women, blood samples were drawn at 15 min intervals for 1 h. An increase in the circulating levels of E3 was observed throughout normal pregnancy and the results were widely distributed. The episodic fluctuations of E3 showed a variation of 13–20 ng/ml during the same 1-h sampling period. The quality control results showed the viability of this RIA in the determination of serum E3 utilizing the iodinated steroid as a tracer.

Radioimmunoassays of human luteinizing and follicle-stimulating hormones using the same radioactive tracer

SummaryThe National Institute of Diabetes, Digestive and Kidney Diseases (NIDDK) provides the hFSH-I-3 preparation, to be employed as a tracer in the radioimmunoassay (RIA) of human follicle-stimulating hormone (hFSH). The contaminating LH contained in that preparation led us to study whether the iodination of such a material could render it a suitable tracer for RIA of both LH and FSH. hFSH-I-3 was labelled with125I by the chloramine-T method and was further purified on Sephadex G-75 column. The LH-RIA was performed using this preparation and anti-LH at a final dilution of 1:37,500, with a sensitivity of 3 mIU LH/ml (2nd international reference pattern). The method was validated by comparing the LH values obtained in different serum samples with those obtained using the standard RIA (125I-LH/anti-LH); the correlation coefficient (r) was equal to 0.9988. No LH overestimation due to the putative cross-reaction with FSH was found. This was demonstrated by testing serum samples containing high (>100 mIU/ml) and low (<10 mIU/ml) concentrations of FSH before and after the treatment with anti-LH. Under these conditions, serum samples from postmenopausal women, pregnant women, normal men and women in basal conditions and after the LH-RH administration, and from a patient with Klinefelter’s syndrome, were evaluated. In conclusion, NIDDK125I-hFSH-I-3 can be used as a tracer for the radioimmunological quantitation of both hLH and hFSH, which results not only inexpensive, but also allows to reduce the amount of the stored radioactive materials.