Follicle-stimulating hormone stimulates circulating gonadotropin surge-attenuating/inhibiting factor bioactivity in cows

Research output: Contribution to journalArticle

12 Citations (Scopus)

Abstract

This study aimed to determine whether superovulation in cattle stimulates gonadotropin surge-attenuating/inhibiting factor (GnSAF/IF) bioactivity, as it does in humans. Blood samples were collected from cows (n = 7 per treatment) at -4, 8, 20, 32, 44, 56, and 68 h after injections of saline, eCG, or FSH. Equal volumes of plasma at each treatment and time point were pooled, and GnSAF/IF and inhibin bioactivities were measured using an established rat pituitary cell culture bioassay. Plasma from saline- and eCG-treated cows had little effect on GnRH-induced LH secretion (116.3 +/- 8.3%-81.6 +/- 6.0% of control), while plasma from FSH-treated cows produced a time-dependent suppression of GnRH-induced LH secretion, falling to 64.6 +/- 4.0% of the control value at 56 h after first FSH injection (p < 0.001). The GnSAF/IF bioactivity from the 56-h plasma eluted at pH 5.73 by pseudochromatofocusing-similar to the GnSAF/IF isoelectric point value of 5.81 determined using serum from superovulated women. Plasma from FSH-treated cows reduced basal FSH secretion more than plasma from eCG-treated cows (to 55.5 +/- 5.7% and 63.2 +/- 6.6% of the control value, respectively, p < 0.01) although immunoreactive inhibin concentrations were similar between the two groups. We conclude that FSH, but not eCG, treatment causes a time-dependent production of circulating GnSAF/IF bioactivity in cattle.

Original languageEnglish
Pages (from-to)278-285
Number of pages8
JournalBiology of Reproduction
Volume57
Issue number2
Publication statusPublished - Aug 1997

Keywords

  • equine chorionic-gonadotropin
  • human menopausal gonadotropin
  • luteinizing-hormone
  • superovulated women
  • factor GNSAF
  • ovarian hyperstimulation
  • preovulatory follicles
  • invitro fertilization
  • plasma-concentrations
  • pituitary-response

Cite this

@article{e21b158d3e794b95a77986bc240ed421,
title = "Follicle-stimulating hormone stimulates circulating gonadotropin surge-attenuating/inhibiting factor bioactivity in cows",
abstract = "This study aimed to determine whether superovulation in cattle stimulates gonadotropin surge-attenuating/inhibiting factor (GnSAF/IF) bioactivity, as it does in humans. Blood samples were collected from cows (n = 7 per treatment) at -4, 8, 20, 32, 44, 56, and 68 h after injections of saline, eCG, or FSH. Equal volumes of plasma at each treatment and time point were pooled, and GnSAF/IF and inhibin bioactivities were measured using an established rat pituitary cell culture bioassay. Plasma from saline- and eCG-treated cows had little effect on GnRH-induced LH secretion (116.3 +/- 8.3{\%}-81.6 +/- 6.0{\%} of control), while plasma from FSH-treated cows produced a time-dependent suppression of GnRH-induced LH secretion, falling to 64.6 +/- 4.0{\%} of the control value at 56 h after first FSH injection (p < 0.001). The GnSAF/IF bioactivity from the 56-h plasma eluted at pH 5.73 by pseudochromatofocusing-similar to the GnSAF/IF isoelectric point value of 5.81 determined using serum from superovulated women. Plasma from FSH-treated cows reduced basal FSH secretion more than plasma from eCG-treated cows (to 55.5 +/- 5.7{\%} and 63.2 +/- 6.6{\%} of the control value, respectively, p < 0.01) although immunoreactive inhibin concentrations were similar between the two groups. We conclude that FSH, but not eCG, treatment causes a time-dependent production of circulating GnSAF/IF bioactivity in cattle.",
keywords = "equine chorionic-gonadotropin, human menopausal gonadotropin, luteinizing-hormone, superovulated women, factor GNSAF, ovarian hyperstimulation, preovulatory follicles, invitro fertilization, plasma-concentrations, pituitary-response",
author = "Fowler, {Paul Alfred Francois} and Price, {Adam Huw}",
year = "1997",
month = "8",
language = "English",
volume = "57",
pages = "278--285",
journal = "Biology of Reproduction",
issn = "0006-3363",
publisher = "Society for the Study of Reproduction",
number = "2",

}

TY - JOUR

T1 - Follicle-stimulating hormone stimulates circulating gonadotropin surge-attenuating/inhibiting factor bioactivity in cows

AU - Fowler, Paul Alfred Francois

AU - Price, Adam Huw

PY - 1997/8

Y1 - 1997/8

N2 - This study aimed to determine whether superovulation in cattle stimulates gonadotropin surge-attenuating/inhibiting factor (GnSAF/IF) bioactivity, as it does in humans. Blood samples were collected from cows (n = 7 per treatment) at -4, 8, 20, 32, 44, 56, and 68 h after injections of saline, eCG, or FSH. Equal volumes of plasma at each treatment and time point were pooled, and GnSAF/IF and inhibin bioactivities were measured using an established rat pituitary cell culture bioassay. Plasma from saline- and eCG-treated cows had little effect on GnRH-induced LH secretion (116.3 +/- 8.3%-81.6 +/- 6.0% of control), while plasma from FSH-treated cows produced a time-dependent suppression of GnRH-induced LH secretion, falling to 64.6 +/- 4.0% of the control value at 56 h after first FSH injection (p < 0.001). The GnSAF/IF bioactivity from the 56-h plasma eluted at pH 5.73 by pseudochromatofocusing-similar to the GnSAF/IF isoelectric point value of 5.81 determined using serum from superovulated women. Plasma from FSH-treated cows reduced basal FSH secretion more than plasma from eCG-treated cows (to 55.5 +/- 5.7% and 63.2 +/- 6.6% of the control value, respectively, p < 0.01) although immunoreactive inhibin concentrations were similar between the two groups. We conclude that FSH, but not eCG, treatment causes a time-dependent production of circulating GnSAF/IF bioactivity in cattle.

AB - This study aimed to determine whether superovulation in cattle stimulates gonadotropin surge-attenuating/inhibiting factor (GnSAF/IF) bioactivity, as it does in humans. Blood samples were collected from cows (n = 7 per treatment) at -4, 8, 20, 32, 44, 56, and 68 h after injections of saline, eCG, or FSH. Equal volumes of plasma at each treatment and time point were pooled, and GnSAF/IF and inhibin bioactivities were measured using an established rat pituitary cell culture bioassay. Plasma from saline- and eCG-treated cows had little effect on GnRH-induced LH secretion (116.3 +/- 8.3%-81.6 +/- 6.0% of control), while plasma from FSH-treated cows produced a time-dependent suppression of GnRH-induced LH secretion, falling to 64.6 +/- 4.0% of the control value at 56 h after first FSH injection (p < 0.001). The GnSAF/IF bioactivity from the 56-h plasma eluted at pH 5.73 by pseudochromatofocusing-similar to the GnSAF/IF isoelectric point value of 5.81 determined using serum from superovulated women. Plasma from FSH-treated cows reduced basal FSH secretion more than plasma from eCG-treated cows (to 55.5 +/- 5.7% and 63.2 +/- 6.6% of the control value, respectively, p < 0.01) although immunoreactive inhibin concentrations were similar between the two groups. We conclude that FSH, but not eCG, treatment causes a time-dependent production of circulating GnSAF/IF bioactivity in cattle.

KW - equine chorionic-gonadotropin

KW - human menopausal gonadotropin

KW - luteinizing-hormone

KW - superovulated women

KW - factor GNSAF

KW - ovarian hyperstimulation

KW - preovulatory follicles

KW - invitro fertilization

KW - plasma-concentrations

KW - pituitary-response

M3 - Article

VL - 57

SP - 278

EP - 285

JO - Biology of Reproduction

JF - Biology of Reproduction

SN - 0006-3363

IS - 2

ER -