Follicle-Stimulating Hormone, Human Chorionic Gonadotropin, and Prolactin Receptors in Hamster Corpora Lutea or Dispersed Luteal Cells during Pregnancy1

Abstract

In vitro progesterone (P4) production by hamster luteal cells is stimulated throughout pregnancy by FSH and LH. Prolactin (PRL) by itself, however, increases P4 synthesis only on Day 12; on Day 4, FSH+LH+PRL induces optimal P4 secretion [Biol Reprod 1994; 51:43-49]. In light of these findings, in this study we investigated FSH, hCG, and PRL receptors in hamster CL or dispersed luteal cells on Days 4, 8, and 12 of pregnancy. Scatchard analysis of hamster CL on Days 4 and 8 showed considerably more unoccupied hCG receptors than FSH receptors: on Day 4, there was 9.5 fmol/mg protein for FSH binding sites vs. 1741 fmol/mg protein for hCG binding. Moreover, the binding affinity of hCG was greater than for FSH: the Day 4 Kd was 0.136 nM for hCG vs. 0.308 for FSH. Similar differences were observed on Day 8. Dispersed luteal cells (large+small cells) were incubated for 24 h with or without 10 ng of ovine FSH, LH, and PRL or human recombinant FSH (r-hFSH), alone or in different combinations. The cells were then washed and incubated for 4 h with iodinated hCG, FSH, or PRL with or without 100-fold excess of unlabeled hormones. The number of binding sites per 200,000 luteal cells did not change appreciably for FSH and hCG on Days 4 and 12 of pregnancy, whereas PRL binding sites significantly increased on Day 12.(ABSTRACT TRUNCATED AT 250 WORDS)

Time-of-flight secondary ion mass spectrometry imaging demonstrates the specific localization of deca-bromo-diphenyl-ether residues in the ovaries and adrenal glands of exposed rats

“…This result could be explained by the fact that all corpora lutea were not at the same stage of development. In species like rat, which have a 4-d long estrous cycle, luteal cells actively synthesize steroids, and progesterone-rich tiny lipid cytoplasmic droplets are present in corpora lutea only at the day of diestrus [48]. In the conditions suitable to enable TOF-SIMS imaging, the produced sections enabled a satisfactory histologic analysis, but did not allow to fully characterizing the histologic stage of corpora lutea.…”

Autoradiographic Analysis of Follicle-Stimulating Hormone and Human Chorionic Gonadotropin Receptors in the Ovary of Immature Rats Treated with Equine Chorionic Gonadotropin1

“…We calculated that 80 pg and 136 pg of labeled FSH and hCG, respectively, were added to the sections; these amounts were sufficient to saturate the ovarian tissue. The binding characteristics of the tracers used in this study were previously evaluated [22]. Representative sections were photographed with either light-or darkfield optics.…”

A microfluidic culture model of the human reproductive tract and 28-day menstrual cycle

“…Briefly, once ovulation occurs, the mature egg is released into the fallopian tube where, if sperm are available, it will be fertilized before moving into the uterus for implantation. The fertilized embryo and newly developing placenta produce and secrete hCG and prolactin at high levels, which rescues the corpus luteum (CL) to support an ongoing pregnancy31. We mimicked this ‘pregnancy'-like state and maintained the CL for the full 14 days of the luteal phase following MFP ovulation in the Quintet-MFP (Fig.…”