Immunoreactive luteinizing hormone in acetone precipitates and kaolin extracts of human urine

Changes of urinary steroid conjugates and gonadotropin excretion in the menstrual cycle and pregnancy in the Yunnan snub-nosed monkey (Rhinopithecus bieti)

The Yunnan snub-nosed monkey (Rhinopithecus bieti) is one of the most endangered species in the world, and it is endemic to China. According to our knowledge, there was no information on reproduction for this species. The present study was designed to understand the characteristics of reproductive hormone secretion during the menstrual cycle and pregnancy of this species by monitoring urinary estrone conjugate (E1C), pregnanediol-3-glucuronide (PdG), bioactive follicle-stimulating hormone (FSH), and luteinizing hormone (LH). The urine samples were collected each day from four adult females for eight menstrual cycles, and once in 3 days during pregnancy (three full-term pregnancies, one mid-term abortion). The steroid conjugate was tested by radioimmunoassays (RIAs), and bioactive FSH and LH levels were measured in vitro by the sensitive bioassays granulosa cell aromatize bioassay (GAB) and rat interstitial cell testosterone (RICT), respectively. The results showed that: 1) E1C presented a preovulatory peak (183.9 +/- 8.6 ng/mgCr) followed by a definite elevation of PdG; 2) PdG in the luteal phase (754.4 +/- 30.6 ng/mgCr) was three- to fivefold higher than during the corresponding follicular phase (198.3 +/- 11.4 ng/mgCr); 3) the peaks of bio-LH and bio-FSH were on the same day, while the E1C peak was 1 or 2 days before the peaks for these two hormones; 4) bio-FSH levels were higher in the follicular phase than in the luteal phase, and bio-LH levels elevated slightly in the luteal phase; 5) the mean cycle length was 23.6 +/- 3.5 days (n = 3) based upon successive urinary LH peaks; 6) based on the interval from the day of E1C peak to the day of parturition, the gestation was 203.7 +/- 2.5 days (n = 3); and 7) both E1C and PdG increased and remained high after pregnancy, with a sharp decrease in basal levels following parturition or mid-term abortion. The results suggested that the pattern of reproductive hormones for R. bieti is similar to that of other Old World monkeys, but the concentration of the hormones is different from that of other species. This species has a longer progestation period, which may be related to its classification status.

Use of the granulosa cell aromatase bioassay for measurement of bioactive follicle-stimulating hormone in urine and serum samples of diverse species

Ovarian steroids and growth factors are intragonadal modulators which augment a key endpoint of follicle-stimulating hormone (FSH) action in granulosa cells: the induction of aromatase activity. Studies of these paracrine hormones that enhance FSH-stimulated estrogen biosynthesis by cultured rat granulosa cells, have led to the development of a sensitive and specific in vitro bioassay for FSH. This newly developed granulosa cell aromatase bioassay (GAB) allows for the measurement of bioactive FSH levels in serum and urine of humans and animals with various physiological and pathological conditions. These studies have demonstrated that the GAB assay is useful in detecting possible changes in the molecular forms of FSH. The adaptation of this method for urine samples allows for the measurement of bio-FSH levels in situations where venipuncture is not practical or in species for which specific radioimmunoassays are not available.

Intranasal nafarelin: an LH-RH analogue treatment of gonadotropin-dependent precocious puberty

The agonistic analogues of luteinizing hormone releasing hormone decrease biochemical findings and clinical signs of gonadotropin-dependent precocious puberty. We tested a new analogue, nafarelin acetate, in 15 girls with gonadotropin-dependent precocious puberty. The hydrophobic nature and potency of this compound allow it to be administered by intranasal inhalation. Laboratory assessment of vaginal cytology, estradiol and urinary gonadotropin levels, and growth velocity revealed that nafarelin acetate 800 to 1200 micrograms/day diminished these values during a 6-month treatment period. These results suggest gonadotropin-dependent precocious puberty in girls can be treated with intranasal administration of nafarelin acetate.

A rapid RIA for LH in serum and first morning void urine--application in an AID programme

A rapid luteinizing hormone (LH) radioimmunoassay, with a 40-min incubation time, has been described and was used to measure the serum and urinary LH profiles in 92 menstrual cycles. A comparison of LH concentrations in first morning voiding (FMV) urine samples demonstrated that the pre-ovulatory LH peak in urine could be detected within 24 h of that in serum and that its offset was somewhat prolonged. FMV urine samples may be used as a convenient alternative to serum for the monitoring of artificial insemination by donor (AID) cycles.

Decreased LH response to the second of consecutive day luteinizing hormone releasing hormone (LHRH) in fusions among patients with constitutional delay of puberty: a phenomenon of pubertal maturation?

Consecutive day LHRH stimulation by continuous infusion has been used to evaluate pituitary reserve. Different responses on the 2 days were not present among non-pubertal hypopituitary patients, pubertal growth hormone deficient patients or adult males. However, patients with constitutionally delayed puberty demonstrated a greater serum LH response on day 1 than day 2. Urinary LH responses suggest a similar but not statistically significant pattern. This response may be a normal phenomenon of puberty or may represent part of the reason for constitutionally delayed puberty.

Evaluation of the double antibody-solid phase radioimmunoassay technique in plasma LH and FSH and urinary LH measurements

Double antibody-solid phase (DASP) radioimmunoassay methods for plasma LH and FSH and urinary LH were developed and carefully evaluated as to their reliability and practicability. The peptide hormones were iodinated enzymatically with immobilized lactoperoxidase which resulted in pure and stable products of unchanged immunoreactivity. The sensitivities of these assay methods are 0.02, 0.17 and 0.20 mIU/tube for plasma LH (MRC 68/40) and FSH (MRC 68/39) and urinary LH (IRP-HMG, urinary), respectively. Interassay coefficients of variation obtained over a 6-18 month period were 14.2, 14.7 and 12.8%, respectively. The latter values for plasma LH and FSH assays were obtained from one level pool samples, and the value for urinary LH is the mean of those obtained from two pools of different levels. Plasma reference values for LH and FSH obtained using these methods are about 1.8-2.9 times higher than those cited for other types of radioimmunoassay. However, the values obtained for LH in urine are similar to those reported in the literature. It is suggested that the DASP technique is less influenced by interference from plasma proteins and because of this gives plasma values closer to the true ones. It is concluded that the methods are well suited for use as routine clinical assays in laboratories with a high work load.

Effect of extraction methods on two pregnancy related, antigenic components of human chorionic gonadotropin preparations

One of the pregnancy related, antigenic components of HCG preparations is not readily detected in kaolin extracts of pregnancy urines; it is however, readily detected in these urines when concentrated by lyophilization or in their benzoic acid extracts.