THE CONVERSION OF PREGNENOLONE TO A MORE ACTIVE PROGESTATIONAL SUBSTANCE BY INCUBATION WITH ENDOCRINE TISSUES IN VITRO

1952 ◽  
Vol 8 (4) ◽  
pp. 329-335 ◽  
Author(s):  
J. A. NISSIM ◽  
J. M. ROBSON
Keyword(s):  
Adrenal Gland ◽  
Corpus Luteum ◽  
Human Placenta ◽  
Corpora Lutea ◽  
Negative Results ◽  
Minced Beef ◽  
Bacterial Action ◽  
Endocrine Tissues ◽  
Intermediate Substance

Incubation of pregnenolone with minced beef corpora lutea resulted in conversion of the steroid to a more active progestational substance as shown by biological assay on the endometrium of the spayed rabbit. Control studies with non-incubated pregnenolone and corpus luteum incubated without steroid, injected separately and in combination, all yielded negative results. To exclude bacterial action, experiments were repeated under sterile conditions, but without diminution in conversion activity. Negative results were obtained when pregnenolone was incubated with spleen, liver or ovaries. The incubation of this steroid with beef adrenal and human placenta, however, resulted in active conversion. It is noteworthy that the adrenal appears to be even more active in the conversion of pregnenolone than the corpus luteum. The association exhibited by the adrenal gland of a lower progesterone content and greater conversion activity, as compared with the corpus luteum, points to progesterone as a likely intermediate substance in the synthesis of the adrenal corticoids.

Blended Effects of Herbal Components of Tokishakuyakusan on Somatomedin C/Insulin-like Growth Factor 1 Level in Rat Corpus Luteum

1991 ◽  
Vol 19 (01) ◽  
pp. 61-64 ◽  
Author(s):  
Satoshi Usuki
Keyword(s):  
Growth Factor ◽  
Corpus Luteum ◽  
Corpora Lutea ◽  
Insulin Like Growth Factor ◽  
Somatomedin C ◽  
Factor I ◽  
Peony Root ◽  
Growth Factor I ◽  
Herbal Components

The effect of herbal components of Tokishakuyakusan on somatomedin C/insulin-like growth factor I (IGF-1) level in medium from rat corpora lutea incubated in vitro was examined. Hoelen + peony root + Japanese angelica root, hoelen + peony root, hoelen + Japanese angelica root or peony root + Japanese angelica root decreased the IGF-1 level. The data suggest that constituent herbal components of Tokishakuyakusan regulate the IGF-1 level by rat corpora lutea.

PROPERTIES OF HUMAN GONADOTROPHINS ELUTED FROM HUMAN CORPUS LUTEUM AND MOUSE LUTEOMA LH-HCG RECEPTORS

1977 ◽  
Vol 84 (1) ◽  
pp. 142-154 ◽  
Author(s):  
F. E. Cole ◽  
P. C. Arquembourg ◽  
B. F. Rice
Keyword(s):  
Corpus Luteum ◽  
Electrophoretic Mobility ◽  
Present Report ◽  
Corpora Lutea ◽  
Fresh Tissue ◽  
Mouse Tissues ◽  
Tissue Receptors ◽  
Human Corpus Luteum

ABSTRACT Studies were performed to try to determine if gonadotrophins are altered during their interaction with tissue receptors. Immunologic, electrophoretic and binding properties of lactoperoxidase labelled [125I]HLH and [125I]HCG were examined before and after elution from mouse luteoma and human corpora lutea receptor preparations. The anti-HCG used in these studies at a 1:10 000 dilution precipitated 92% of a freshly iodinated [125I]HCG preparation. Receptor eluted [125I]HCG, derived from the same batch of labelled ligand, was virtually quantitatively precipitated by the same dilution of anti-HCG. [125I]HCG eluted from the human corpus luteum was electrophoretically more homogenous when compared to its heterogenous parent labelled preparation and migrated to a position similar to that of native HCG. In Ouchterlony double diffusion experiments against anti-HCG antiserum, corpus luteum eluted [125I]HCG and [125I]HLH showed immunologic identity with each other as well as with native HCG and HLH. Receptor eluted [125I]HCG from the mouse luteoma, following in vivo administration via tail vein injection or after incubation in vitro with labelled hormones, was immunologically indistinguishable from native HCG. The electrophoretic mobility of HCG was retarded when HCG was added to extracts of mouse luteoma, liver and kidney. Eluates of mouse luteoma, applied to Bio-Gel columns previously equilibrated with [125I]HCG showed the ability to concentrate [125I]HCG in the high molecular weight column fractions. Similar results were obtained with columns equilibrated with [125I]TSH and [125I]HGH. [125I]HCG eluted from the mouse luteoma was able to bind to fresh luteoma homogenate but, in contrast to an earlier report with [125I]HCG eluted from rat testis, no enhancement of binding of the eluted [125I]HCG was observed with fresh tissue. These results could be explained by the extraction of non-dialyzable intracellular component during the [125I]HCG elution procedure from the luteoma homogenate which combines with HCG to lower its binding and alter its electrophoretic mobility. This component could be extracted from other mouse tissues and combines with other labelled peptide hormones. Data in the present report support in part the hypothesis that gonadotrophins eluted from mouse luteoma and human corpus luteum are not altered by their interaction with tissue receptors.

ÉTUDE DE L'ACTIVITÉ BIOLOGIQUE IN VITRO DES HORMONES GONADOTROPES

1963 ◽  
Vol 42 (4) ◽  
pp. 498-508 ◽  
Author(s):  
D. Gospodarowicz ◽  
J. Legault-Démare
Keyword(s):  
Corpus Luteum ◽  
Corpora Lutea ◽  
Lactogenic Hormone ◽  
Different Temperatures ◽  
Pregnant Mare Serum Gonadotrophin

ABSTRACT Temperature has been shown to have a profound effect on the incorporation of 14C acetate into steroids by rat corpus luteum in vitro. The variations of temperature affected to a different extent the labelling of progesterone and androstenedione. Differences were also found between cyclic and pseudopregnancy corpora lutea studied at different temperatures and stimulated or not by pregnant mare serum gonadotrophin (PMS) in vitro. These results are consistent with the hypothesis that progesterone and androstenedione are synthesized through different pathways. They also suggest that lactogenic hormone stimulates specifically the synthesis of androstenedione.

IN-VITRO STEROIDOGENESIS OF NEWLY FORMED CORPORA LUTEA AND THE NON-LUTEAL OVARY IN THE RAT, RABBIT, HAMSTER AND GUINEA-PIG

1980 ◽  
Vol 84 (1) ◽  
pp. 101-108 ◽  
Author(s):  
P. F. TERRANOVA ◽  
S. K. SAIDAPUR ◽  
G. S. GREENWALD
Keyword(s):  
Guinea Pig ◽  
Corpus Luteum ◽  
Ovarian Function ◽  
Serum Testosterone ◽  
The Other ◽  
Corpora Lutea ◽  
Serum Progesterone ◽  
Antral Follicles ◽  
Baseline Levels

The steroidogenic abilities of the newly formed corpus luteum (8–10 h after ovulation) and the non-luteal ovary were compared in the guinea-pig, hamster, rabbit and rat using an invitro incubation technique. Histologically, newly formed rat corpora lutea (CL) were highly luteinized whereas the CL of the rabbit and guinea-pig were only partially luteinized. The CL of the hamster showed the least amount of luteinization. Serum progesterone was highest in the rat (18 ± 3 (s.e.m.) ng/ml). In the hamster, it was about 8 ng/ml, whereas in the rabbit and guinea-pig it was about 1 ng/ml. Serum androstenedione ranged between 0·5 and 1 ng/ml. Serum testosterone was lowest in the hamster (60 pg/ml) and highest in the rabbit (470 pg/ml), whereas in the rat and guinea-pig, testosterone levels were similar (about 240 pg/ml). Serum oestrogens were at baseline levels in all species. The CL of the rat exhibited considerably greater steroidogenic ability than the CL of the other species, producing 70 ± 6 ng progesterone/mg per h, 215 ± 14 pg androstenedione/mg per h, 49 ± 3 pg testosterone/mg per h, 3 pg oestrone/mg per h and 1 pg oestradiol/mg per h. Rabbit CL produced only progesterone (7 ± 2 ng/mg per h). Newly formed hamster CL produced none of the above steroids. In general, the ability of the CL to produce progesterone in vitro correlated with the degree of luteinization found by histological observation. Guinea-pig CL were embedded deeply in the ovary and could not be obtained without damage. Consequently, a portion of the ovary containing a corpus luteum was incubated. There was no difference in the steroid production by this portion of the ovary compared with the non-luteal ovary. The non-luteal ovary of the rat produced the highest amount of progesterone (10 ± 2 ng/mg per h). The guinea-pig non-luteal ovary produced about 5 ± 2 ng progesterone/mg per h, whereas the non-luteal ovary of the rabbit did not produce any. On the other hand, the hamster non-luteal ovary lost progesterone. Non-luteal ovaries from all species produced androgens. The non-luteal ovary of the guinea-pig contained especially large numbers of atretic antral follicles. The guinea-pig non-luteal ovary produced extremely large amounts of androstenedione (1110 ± 210 pg/mg per h) and testosterone (606 ± 154 pg/mg per h) compared with the amounts produced by the non-luteal ovary of the rat, hamster and rabbit. In the non-luteal ovary, interstitium and atretic antral follicles are the probable source of androgens. Oestrogen production by the non-luteal ovary was at baseline levels in the four species studied correlating with the absence of healthy antral follicles. The results indicate the extreme species differences that exist in ovarian function in the early postovulatory period.

Corpus luteum and endometrial function in ewes post partum: a study in vivo and in vitro

1992 ◽  
Vol 4 (1) ◽  
pp. 77 ◽  
Author(s):  
JM Wallace ◽  
CJ Ashworth ◽  
RP Aitken ◽  
MA Cheyne
Keyword(s):  
Corpus Luteum ◽  
Post Partum ◽  
Polyacrylamide Gel Electrophoresis ◽  
Uterine Horn ◽  
Corpora Lutea ◽  
Luteal Function ◽  
Progesterone Production ◽  
Release Device

Induction of ovulation post partum is associated with a high incidence of prematurely regressing corpora lutea. However, inadequate luteal function is not the sole reason for pregnancy failure, because ewes with normal corpus luteum function and successful fertilization also fail to establish pregnancies. The effects of suckling status and the interval from post partum to rebreeding on corpus luteum and endometrial function were examined in vivo and in vitro. Ewes were weaned early or allowed to lactate, induced to ovulate using a progesterone-impregnated controlled internal drug release device and an intramuscular injection of pregnant mare serum gonadotrophin, and inseminated (intrauterine) at either 21 or 35 days post partum (n = 10 per group). A further 10 standard ewes whose interval from parturition was in excess of 150 days were included for comparative purposes. On Day 10 after insemination the pregnancy rate was determined in four ewes from each of the post-partum groups and five standard ewes. These ewes were then ovariectomized and hysterectomized for studies in vitro. The incidence of premature luteal regression, as assessed by progesterone concentrations in peripheral blood was independent of the suckling stimulus but dependent on stage post partum (21 days post partum, 6 of 19 ewes; 35 days post partum, 0 of 19 ewes; P less than 0.05). Luteal function was normal in all standard ewes. Ovulation rate, corpus luteum weight, corpus luteum progesterone content and basal progesterone production in vitro were significantly less in 21-day than in 35-day post-partum ewes. Pregnancy rates as determined on Day 10 or at term were low in all post-partum groups (7 out of the 38 ewes inseminated) compared with standard ewes (8 of 10). Uterine function was assessed by culturing endometrial tissue from the tip and body of each uterine horn in the presence of [3H]leucine for 30 h at 37 degrees C. Incorporation of radiolabel into non-dialysable proteins synthesized and secreted by the endometrium in vitro was independent of uterine horn location and suckling status but was significantly lower (P less than 0.001) in media from 21-day than from 35-day post-partum ewes. Irrespective of treatment group, incorporation of radiolabel was positively correlated with mean plasma progesterone concentrations on Days 2-10 after insemination and with basal progesterone production in vitro. Secreted proteins were detected by two-dimensional-polyacrylamide-gel electrophoresis and fluorography.(ABSTRACT TRUNCATED AT 400 WORDS)

STEROID AND PROSTAGLANDIN SECRETION BY THE CORPUS LUTEUM, ENDOMETRIUM AND EMBRYOS OF CYCLIC AND PREGNANT PIGS

1979 ◽  
Vol 82 (3) ◽  
pp. 425-428 ◽  
Author(s):  
J. WATSON ◽  
C. E. PATEK
Keyword(s):  
Corpus Luteum ◽  
Late Stage ◽  
Oestrous Cycle ◽  
Corpora Lutea ◽  
Reproductive Tissues ◽  
Prostaglandin F

Prostaglandin F2α (PGF2α) secreted by the reproductive tissues of the pig in vitro was measured and it was found that the levels secreted by the corpus luteum and endometrium of early pregnant sows were significantly lower than those secreted by tissues during the late stage of the oestrous cycle. They were, however, comparable to levels secreted by tissues from the mid-stage of the oestrous cycle. Embryos also secreted significant amounts of PGF2α. Secretion of progesterone and oestradiol by the corpora lutea of both cyclic and pregnant pigs fell within accepted limits but embryos were also found to secrete significant amounts of oestradiol. The results suggest that luteal maintenance in the early pregnant pig is unlikely to be directly due to reduced synthesis of PGF2α.

SUPERFUSION IN VITRO IN THE STUDY OF OVARIAN STEROIDOGENESIS

1975 ◽  
Vol 64 (1) ◽  
pp. 163-173 ◽  
Author(s):  
JOHN WATSON ◽  
J. T. S. LEASK
Keyword(s):  
Luteinizing Hormone ◽  
Corpus Luteum ◽  
Transient Increase ◽  
Corpora Lutea ◽  
Ovarian Steroidogenesis ◽  
Steroid Secretion ◽  
Regulatory Factors ◽  
Prolonged Response

SUMMARY A method for the continuous superfusion of porcine corpus luteum tissue is described which readily allows both the introduction of regulatory factors to the incubating tissue, and sampling of the tissue. Oestrogen (principally oestradiol) and progestin (principally progesterone) can be measured for up to 24 h in the superfusate from corpora lutea of all ages, and the secretion of both steroids is stimulated by the addition of luteinizing hormone. The pattern of response of both steroids to a pulse of gonadotrophin was similar in that a rapid transient increase in secretion occurred followed some time later by a secondary and more prolonged response. A second pulse of gonadotrophin introduced 6 h after the first also stimulated steroid secretion, indicating that during superfusion in vitro the porcine corpus luteum does not become refractory to the steroidogenic effect of gonadotrophin.

FORMATION OF STEROID HORMONES IN VITRO BY DEVELOPING CORPORA LUTEA OF THE RABBIT

1977 ◽  
Vol 75 (3) ◽  
pp. 355-361 ◽  
Author(s):  
AKIRA SUZUKI ◽  
TAKAHIDE MORI ◽  
TOSHIO NISHIMURA
Keyword(s):  
Corpus Luteum ◽  
Initial Step ◽  
Chorionic Gonadotrophin ◽  
Human Chorionic Gonadotrophin ◽  
Temporary Increase ◽  
Corpora Lutea ◽  
Sharp Rise ◽  
17 Hydroxyprogesterone ◽  
Qualitative Changes

Rabbits were injected with human chorionic gonadotrophin (HCG), and slices of developing corpora lutea taken from the ovaries 15, 18, 24, 48, 72 and 96 h after injection were incubated with [1-14C]sodium acetate at 37 °C for 3 h. The incorporation of labelled acetate into ten steroids, including progestagens, androgens and oestrogens, was analysed. In the initial step of corpus luteal formation, the specific incorporation (incorporation of [1-14C]acetate/100 mg tissue) increased sharply. The major steroidal products were progesterone, 17-hydroxyprogesterone and 20α-hydroxypregn-4-en-3-one. Between 18 and 48 h, the increase in specific incorporation was more gradual than in the initial step. Although the pattern was also dominated by progestagens, a temporary increase in the incorporation of acetate into androgens and oestrogens was observed. In the final step, a sharp rise in the total incorporation (incorporation of [1-14C]acetate/corpus luteum) was found, whereas the specific incorporation increased only slightly. The principal steroids produced were progesterone, pregnenolone and 20α-hydroxypregn-4-en-3-one. Incorporation into C19 steroids declined markedly and that into C18 steroids could not be detected. This profile of steroidogenesis 96 h after injection of HCG was similar to that of the corpus luteum in pregnancy. Thus marked quantitative and qualitative changes have been demonstrated during the period of formation of corpora lutea in the rabbit.

Spontaneous apoptosis of cells prepared from the nonregressing corpus luteum

1994 ◽  
Vol 72 (11-12) ◽  
pp. 531-536 ◽  
Author(s):  
Nicholas Kenny ◽  
Rachel E. Williams ◽  
Lorraine B. Kelm
Keyword(s):  
Corpus Luteum ◽  
Apoptotic Cell ◽  
Tyrosine Phosphatase ◽  
Cell Types ◽  
In Vitro Models ◽  
Luteal Cell ◽  
Corpora Lutea ◽  
Spontaneous Apoptosis ◽  
Survival Signal

At the end of a nonconception estrous cycle, the sheep corpus luteum undergoes involution (luteolysis), a process thought to involve apoptotic deletion of cells. It is not yet clear which of the heterogeneous luteal cell types is involved or what mechanisms drive the apoptotic progression. We examined intact paraffin-embedded corpora lutea (in situ terminal dUTP nick end-labeling method) and found direct evidence for apoptotic deletion of cells during luteolysis, but not in healthy, nonregressing corpora lutea. We then sought to implement in vitro models to dissect apoptotic mechanisms in the constituent cells of the corpus luteum. Cells prepared using standard collagenase dispersion of corpus luteum were evaluated for evidence of apoptosis (DNA laddering) by direct agarose gel electrophoresis, a method that obviates the need for DNA extraction, so allowing examination of relatively few cells (≤ 0.5 × 106). When cells were prepared from nonregressing corpus luteum for in vitro manipulation, a population(s) of cells undergoing spontaneous apoptosis was detected. Apoptosis was inhibited by Zn2+ (5 mM), by the tyrosine phosphatase inhibitor sodium orthovanadate (100 μM), or by maintenance at 4 °C. It appears that simple collagenase digestion of intact corpus luteum removes a subset of constituent cells from their survival signal, leading to rapid initiation of endonuclease activity and apoptotic cell death. Identification of the required survival factors and their actions is being pursued to facilitate development of appropriate in vitro models for this endocrine system.Key words: corpus luteum, apoptosis.

Oxytocin determination in steroid producing tissues and in vitro production in ovarian follicles

1985 ◽  
Vol 109 (4) ◽  
pp. 530-536 ◽  
Author(s):  
D. Schams ◽  
Th. A. M. Kruip ◽  
R. Koll
Keyword(s):  
Corpus Luteum ◽  
Granulosa Cells ◽  
Follicular Fluid ◽  
De Novo ◽  
Prostate Gland ◽  
Seminal Vesicles ◽  
Corpora Lutea ◽  
In Vitro Production ◽  
Wet Weight

Abstract Immunoreactive oxytocin was measured in ovaries (corpus luteum and follicular fluid) and adrenals of cows, and in testes, seminal vesicles, prostate gland and adrenals of bulls. Secretion of oxytocin was further measured after culture of whole follicles, granulosa cells and theca tissue. Concentrations of oxytocin increased in corpora lutea of cycling cattle until mid-luteal phase (447 ± 93 ng/g wet weight) and decreased afterwards. Low concentrations were found in corpora lutea of pregnant animals (6 ± 3 ng/g wet weight). Follicular fluid contains some oxytocin (on average 42–108 pg/ml) but concentrations were significantly higher in the fluid of ovarian cysts (190 pg/ml). After culture of follicles the amount of oxytocin released into the medium increased indicating de novo synthesis. The granulosa cells were the main source of follicular oxytocin. Production increased during luteinization indicating that luteinization is an important step for the production of oxytocin in ovaries. Tissues of testes (65 ± 10 pg/g wet weight) and adrenals from cows (122 ± 39 pg/g wet weight) and bulls (111 ±2 pg/g wet weight) contained oxytocin but at much lower concentrations compared to corpus luteum tissue. About 10 times higher concentrations of oxytocin were measured in the adrenal medulla (717 ± 96 pg/g wet weight) compared to the cortex (72 ± 11 pg/g wet weight). Seminal vesicles and prostate gland contained no measurable amounts of oxytocin (< 5 pg/g wet weight).

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