Gonadotropins of the Swine Pituitary I. Various Biological Effects of Purified Thylakentrin (Fsh) and Pure Metakentrin (Icsh)

Abstract

NEW BRUNSWICK, NEW JERSEY\ EVERAL RECENT STUDIES from this laboratory offer strong support of the belief (i) that at least two gonadotropins can be isolated from extracts of pituitary glands. Preliminary evidence was obtained from experiments with extracts of hog glands digested by proteolytic enzymes permitting differentiation of gametogenic ('follicle stimulating') and interstitial cell'Stimulating effects depending upon the en' zyme used and the extent of digestion (2). Physicochemical methods were next em' ployed to separate the gonadotropins from hog pituitary extracts which had not undergone preliminary enzymic hydrolysis (3). The interstitial cell'Stimulating hor' mone as a pure protein was isolated (4). The gametogenic hormone was separated as a substance with only one apparent biological effect; however, the purest preparations contained small proportions of two contaminating impurities.Work in the University of California (5) likewise led to the isolation of interstitial cell'Stimulating hormone from pituitary glands of another mammal, the sheep. We have had the opportunity of making a limited examination of the potency and bio' logical action of this extract believed, like our hog pituitary protein, to be a pure sub' stance.In this report and the two which follow it, the term thylakentrin will be used to refer to the gametogenic hormone (FSH or follick'Stimulating hormone) and the term metakentrin will refer to the interstitial cell'Stimulating hormone (ICSH and, in a restricted sense only, luteinizjng hormone). The basis for suggesting these names is given by Coffin and van Dyke (6).The results of a ramified investigation of the biological action of pure metakentrin as well as more restricted and less elaborate biological experiments with thylakentrin will be described in this first report. The second report will deal completely with a simplified method of securing pure metakentrin. Physicochemical evidence of purity as well as additional biological data important for demonstrating that the protein is the hormone will also be presented. The third and last report will offer immunological evidence not only of the purity of hog metakentrin but also of its striking immunologi' cal difference from sheep metakentrin whether in crude extract or in pure form.Unless otherwise noted, the metakentrin was the pure protein derived from hog pituitary glands and the thylakentrin, of similar origin, was about 80 per cent pure. 1

Effects of short-term injection of gonadotrophins on ovarian follicle development in hypogonadal (hpg) mice

“…LER 8/116 has a potency of 35 NIH-FSH-S1 units/mg (i.e. 35 i.u./mg) as determined by the hCG augmentation bioassay, and it has an extremely low contami¬ nation with LH, estimated at 5-2 i.u./mg by the ventral prostate weight gain bioassay (Greep et al, 1942) equivalent to less than 001 NIH-LH-S1 units/mg (L. E. Reichert, personal communication). Sheep LH, NIH-oLH-S24, again kindly supplied by NIADDK, was used for all the experiments involving LH.…”

Suppression of the secondary FSH surge with bovine follicular fluid is associated with delayed ovarian follicular development in heifers

“…The pituitary gonadotrophins LH and FSH are both necessary for ovarian follicular development (Greep et al, 1942), but the relative roles of these hormones in stimulating folliculogenesis are not fully understood. During the bovine oestrous cycle, preovulatory surges of LH and FSH occur simultaneously (Dobson, 1978; and basal plasma concentrations are parallel throughout much of the luteal phase (Rahe et al, 1980;Schallenberger et ai, 1985).…”

Postovulatory steroidogenesis after ovulation induced by LH or FSH in hypophysectomized pro-oestrous hamsters

“…Antral follicles, in particular the granulosa cells, are the major sites of oestrogen synthesis in the hamster (Makris & Ryan, 1975 Armstrong & Papkoff, 1976;Erickson & Hsueh, 1978). Since LH treatment results in histological evidence of stimulation of theca interna cells and interstitial cells in hypophysectomized rats (Greep, Van Dyke & Chow, 1942;Lostroh & Johnson, 1966) and since these cells contain LH receptors (Zeleznik, Midgley & Reichert, 1974), it seems likely that in the present study these cells are responsible for the increased production of testosterone after LH treatment. The increased weight of residual tissue after LH treatment ( …”