Effects of Human Menopausal Gonadotrophin Preparations in Different Bioassay Methods

Hell, H. van; Matthijsen, Robert A.; Overbeek, G. A.

doi:10.1530/acta.0.0470409

Cited by 41 publications

(6 citation statements)

References 8 publications

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“…Thus species of LH with longer plasma half-lives had higher potency ratios by ventral prostate weight gain (VPW) assay (Greep, van Dyke & Chow, 1941): OAAD assay (Parlow, 1961) than those with shorter plasma half-lives (Parlow, 1968). This is consistent with the longer dose-response time-intervals of the SVW (van Hell, Matthijsen & Overbeek, 1964) and VPW assays (3 or 4 days with repeated s.c. doses) than of the OAAD assay (3 or 4 h after i.v. dosing).…”

Section: Introductionsupporting

confidence: 87%

Plasma clearance in the rat of the LH bioactivity of two human LH standards of differing molecular composition

Storring

Khan²,

Mistry³

et al. 1988

Journal of Endocrinology

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The LH biological potency of the International Reference Preparation (IRP) of Human Pituitary LH for Immunoassay (IRP 68/40) relative to that of the 2nd IRP of Human Pituitary FSH and LH for Bioassay (IRP 78/549) is markedly greater when estimated by in-vitro interstitial cell testosterone production (TICT) bioassay than by in-vivo bioassay, and by the 4-h ovarian ascorbate depletion (OAAD) assay than by the 4-day seminal vesicle weight gain assay. Other preparations of human LH which, like IRP 68/40, were highly purified, showed a similar spectrum of bioactivity in these assay systems and also contained a higher proportion of more basic LH isoforms than are found in crude pituitary extracts such as IRP 78/549. In an attempt to explain these differences, a comparison was made of the plasma survival in rats of the LH bioactivity (by TICT assay) of these two preparations. Contrary to expectation, their relative plasma clearance rates over a 4-h period did not account for their differing bioactivities. The plasma half-life of the LH bioactivity (with 95% confidence limits) was estimated to be 42.4 (35.3-49.5) min for IRP 68/40 and 41.3 (31.5-51.0) min for IRP 78/549. Furthermore the time-course of action in vivo of IRP 78/549 did not appear to be more prolonged than that of IRP 68/40. Thus their plasma testosterone responses during the course of these 4-h plasma clearance studies were similar, and estimates of the LH potency of IRP 68/40 relative to that of IRP 78/549 were no greater by 2-h than by 4-h OAAD assay.(ABSTRACT TRUNCATED AT 250 WORDS)

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Section: Introductionsupporting

confidence: 87%

Plasma clearance in the rat of the LH bioactivity of two human LH standards of differing molecular composition

Storring

Khan²,

Mistry³

et al. 1988

Journal of Endocrinology

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“…organ weight) of hormones injected in a living rat or mouse [6] to evaluate gonadotropin bioactivity, thus inferring their dosage for clinical purposes [7]. Indeed, official Pharmacopoeias recognize the biological activity of LH and hCG preparations as determined by the so-called “Van Hell bioassay” [8]. Briefly, a fixed dose of gonadotropin is administered by daily subcutaneous injection in groups of ten 21–28 days old immature male rats.…”

Section: Introductionmentioning

confidence: 99%

Human LH and hCG stimulate differently the early signalling pathways but result in equal testosterone synthesis in mouse Leydig cells in vitro

Riccetti

Pascali

Gilioli

et al. 2017

Reprod Biol Endocrinol

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BackgroundHuman luteinizing hormone (LH) and chorionic gonadotropin (hCG) are glycoprotein hormones regulating development and reproductive functions by acting on the same receptor (LHCGR). We compared the LH and hCG activity in gonadal cells from male mouse in vitro, i.e. primary Leydig cells, which is a common tool used for gonadotropin bioassay. Murine Leydig cells are naturally expressing the murine LH receptor (mLhr), which binds human LH/hCG.MethodsCultured Leydig cells were treated by increasing doses of recombinant LH and hCG, and cell signaling, gene expression and steroid synthesis were evaluated.ResultsWe found that hCG is about 10-fold more potent than LH in cAMP recruitment, and slightly but significantly more potent on cAMP-dependent Erk1/2 phosphorylation. However, no significant differences occur between LH and hCG treatments, measured as activation of downstream signals, such as Creb phosphorylation, Stard1 gene expression and testosterone synthesis.ConclusionsThese data demonstrate that the responses to human LH/hCG are only quantitatively and not qualitatively different in murine cells, at least in terms of cAMP and Erk1/2 activation, and equal in activating downstream steroidogenic events. This is at odds with what we previously described in human primary granulosa cells, where LHCGR mediates a different pattern of signaling cascades, depending on the natural ligand. This finding is relevant for gonadotropin quantification used in the official pharmacopoeia, which are based on murine, in vivo bioassay and rely on the evaluation of long-term, testosterone-dependent effects mediated by rodent receptor.Electronic supplementary materialThe online version of this article (doi:10.1186/s12958-016-0224-3) contains supplementary material, which is available to authorized users.

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“…In particular they were asked, if possible, to contribute FSH estimates by the augmented ovarian weight gain (AOW) method (Steelman & Pohley 1953), and LH estimates by the seminal vesicle weight gain (SVW) method (Van Hell et al 1964) and the ovarian ascorbate depletion (OAAD) method (Parlow 1961). Participants were asked to assume an FSH potency of 70 IU/ampoule and an LH potency of 60 IU/ampoule for assays of the IS and its accelerated thermal degradation samples.…”

Section: Design Of the Studymentioning

confidence: 99%

“…The assay as originally described by Van Hell et al (1964) used pre-pubertal rats of unspecified strain with ages in the range from 21 to 28 days. (The age range of rats for the SVW assay described in the British Pharmacopoeia (2000) and European Pharmacopoeia (1997) is 19-28 days, and for that described in the United States Pharmacopoeia (2000) is 20-21 days.…”

Section: Selectivity Of Svw Assaysmentioning

confidence: 99%

The fourth International Standard for Human Urinary FSH and LH: specificities of LH seminal vesicle weight gain assays in the collaborative study differ between laboratories

Storring

Das²

2001

Journal of Endocrinology

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The fourth International Standard for Human Urinary FSH and LH (IS; in ampoules coded 98/704) was compared with the third International Standard for Urinary FSH and LH (IS 71/264) by 10 laboratories in nine countries, using FSH and LH in vivo bioassays.Estimates of the FSH content of the IS by augmented ovarian weight gain assays were homogeneous within each laboratory and over all laboratories. The combined weighted geometric mean estimate of FSH content of the IS (with 95% fiducial limits) in terms of IS 71/264 was 71·9 (69·0-74·9) IU/ampoule.Although estimates by seminal vesicle weight gain (SVW) assays of the relative LH activities of the IS and IS 71/264 were homogeneous within laboratories, estimates were heterogeneous between laboratories. This indicated differences between the spectrum of LH isoforms in the IS and IS 71/264, which were obtained from different manufacturers, and differences between the specificities of SVW assays performed in different laboratories. The differences between the specificities of SVW assays appeared to be related to interactions among mean laboratory seminal vesicle weights, age and genetic strain of rat. The finding of inter-laboratory differences in the specificities of SVW assays is of some significance, as this assay method has been generally adopted by Pharmacopoeias for the control of the LH content of therapeutic products. The combined unweighted geometric mean estimate of LH content of the IS (with 95% fiducial limits) in terms of IS 71/264 by SVW and ovarian ascorbate depletion assays was 70·2 (61·7-80·0) IU/ampoule.Estimates of the FSH and LH content of ampoules of the IS kept at increased temperatures suggested that the IS would be adequately stable under normal storage conditions.On the basis of these results, the World Health Organization Expert Committee on Biological Standardization established the preparation in ampoules coded 98/704 as the fourth International Standard for Human Urinary FSH and LH, and assigned to the contents of each ampoule an activity of 72 International Units of urinary FSH and an activity of 70 International Units of urinary LH.

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Effects of Human Menopausal Gonadotrophin Preparations in Different Bioassay Methods

Cited by 41 publications

References 8 publications

Plasma clearance in the rat of the LH bioactivity of two human LH standards of differing molecular composition

Plasma clearance in the rat of the LH bioactivity of two human LH standards of differing molecular composition

Human LH and hCG stimulate differently the early signalling pathways but result in equal testosterone synthesis in mouse Leydig cells in vitro

The fourth International Standard for Human Urinary FSH and LH: specificities of LH seminal vesicle weight gain assays in the collaborative study differ between laboratories

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