A batch of 24 mg of luteinizing hormone-human chorionic gonadotropin (LH-hCG) receptor was isolated from bovine corpora lutea. The LH-hCG receptor showed specific binding with hCG. The receptor-hCG complex activated the regulatory Ns protein isolated from rabbit liver, which in turn stimulated adenylate cyclase to convert ATP into cAMP in vitro, attesting to the biological activity of the purified LH-hCG receptor. The LH-hCG receptor was treated with 2% sodium dodecyl sulfate (SDS) to prepare the molecular weight (Mr) 280K dimer and with 50 mM dithiothreitol (DTT) to prepare the Mr 120K monomer and subunits of Mr 85K and 38K. Oligomers of various molecular weights were recovered from gel filtration columns due to the reassociation of disulfide bonds between monomers and subunits. Hence, the receptor monomer was also dissociated into subunits of Mr 85K and 38K by reduction of -S-S-bonds with 50 mM DTT in 2% SDS and alkylation of sulfhydryl groups in the presence of 100 mM N-ethyl-maleimide. The subunits were separated by gel filtration through columns of Ultrogel AcA-44 and Sephadex G-75. The yields of the purified alkylated subunits of Mr 85K and 38K were 1.8 and 1.5 mg, respectively. Each subunit migrated as a single entity in SDS-polyacrylamide gel electrophoresis. The monomer of the receptor of Mr 120K showed specific binding with 125I-hCG, suggesting it to be the minimum molecular weight functional unit of the receptor. The Mr 85K and 38K subunits bound 125I-hCG, which could not be displaced with unlabeled hCG.(ABSTRACT TRUNCATED AT 250 WORDS)

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Background:The aim of this study was to investigate the level of estrogen receptors (ERs) and progesterone receptors (PRs) of the human endometrium and myometrium in physiological and pathological states. Endometrial cancer and myoma represent some of the prevailing diseases of the reproductive system in women, affecting 6% of the adult female population.Method: Scat chard plot analysis was used to evaluate the levels of ERs and PRs (fmol/mg protein) in postmenopausal women with physiological endometrium (n=20); malignant endometrium (n=20); women with physiological myometrium (n=20) and with myoma (n=20) with a mean age of 55 years for each group. Results:The physiological level of PR in the endometrium (527 ± 61.2fmol/protein) exceeds that of malignant endometrial tissue (321 ± 41.9fmol/protein), while the level of ER changes only insignificantly. The level of ERs and PRs assessed in healthy patients (36 ± 1.2fmol/protein; 288 ± 15.3fmol/protein, respectively) were lower than in patients with myoma (118 ± 5.4fmol/protein; 967 ± 67.8fmol/protein, respectively). Conclusion:The increase of both ERs and PRs reveals endocrine-dependent benign processes, while the decrease of PRs and especially the decrease of the PR/ER ratio indicate disease pathogenesis in the endometrium.

Background.The present study demonstrates changes in the serum osteocalcin concentration after oral administration of calcium in patients with hypercalciuria, nephrolithiasis and primary hyperparathyroidism and the osteocalcin serum concentration as a differential diagnostic value for hypercalciurias. Eight of the control patients showed normal values of the serum osteocalcin during the control period with no calcium administration and the experimental period of OCTT, as follows: X1 = 3.05 ± 0.6 pmol/L and X2 = 3.65 ± l.1 pmol/L. The ninth patient from the control group showed an acute increase of the osteocalcin values-17.8 ± 3.8 respectively 23.9 ± 4.2 pmol/L during the experimental period of OCTT and he has been excluded from the study. The patients with absorptive hypercalciuria and recurrent calcium nephrolithiasis similar to the controls showed an increase of the serum osteocalcin during the experimental period of OCCT from 2.11 ± 0.30 pmol/l to 3.36; ± 0.7 pmol/L, p>0.1, non-significant.Obviously serum osteocalcin level assessment does not contribute to the differential diagnosis in patients with hypercalciuria, but nevertheless it demonstrates the presence of the hormonal statement, involved in the regulation of Ca metabolism. An acute rise of serum osteocalcin levels was found after the oral calcium tolerance test in patients with renal hypercalciuria and osteoporosis.The administration of calcium activates the osteosynthesis processes and the release of high quantities of osteocalcin. The study of the serum osteocalcin gives more possibilities to estimate the status of the bone system when pathological changes such as hyperparathyroidism, renal hypercalciuria and osteoporosis occur.

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