PROGESTERONE SYNTHESIS IN RESPONSE TO LUTEINIZING HORMONE BY RAT OVARIAN TISSUE IN VITRO

1971 ◽  
Vol 49 (3) ◽  
pp. 471-478 ◽  
Author(s):  
J. WATSON
Keyword(s):  
Ascorbic Acid ◽  
Luteinizing Hormone ◽  
Ovarian Tissue ◽  
Large Numbers ◽  
Progesterone Synthesis ◽  
Immature Rats ◽  
Increased Sensitivity ◽  
High Degree ◽  
Pregnant Mare Serum Gonadotrophin

SUMMARY A bioassay for luteinizing hormone (LH) activity is described. The method depends on progesterone synthesis by pooled, sliced rat ovarian tissue in vitro, the ovaries being obtained from immature rats pretreated with pregnant mare serum gonadotrophin. The main advantage of the method is its increased sensitivity compared with the commonly used ovarian ascorbic acid depletion assay, its high degree of precision, and the fact that it allows the use of large numbers of well randomized samples from a small group of animals.

EFFECTS OF LUTEINIZING HORMONE AND NICOTINAMIDE ADENINE DINUCLEOTIDE PHOSPHATE ON SYNTHESIS OF PROGESTATIONAL STEROIDS BY RABBIT OVARIAN TISSUE IN VITRO

1966 ◽  
Vol 35 (1) ◽  
pp. 65-73 ◽  
Author(s):  
J. H. DORRINGTON ◽  
R. KILPATRICK
Keyword(s):  
Luteinizing Hormone ◽  
Nicotinamide Adenine Dinucleotide ◽  
Ovarian Tissue ◽  
Nicotinamide Adenine Dinucleotide Phosphate ◽  
Nicotinamide Adenine ◽  
Steroid Synthesis ◽  
Activity Measurements ◽  
Progesterone Synthesis ◽  
Stimulation Of

SUMMARY Luteinizing hormone (LH) stimulated synthesis of both progesterone and 20α-hydroxypregn-4-en-3-one by rabbit ovarian tissue in vitro. Progesterone synthesis was stimulated by nicotinamide adenine dinucleotide phosphate (NADP), but 20α-hydroxypregn-4-en-3-one production was only slightly affected by NADP compared with the effect of LH. When NADP was added with glucose-6-phosphate (G-6-P) or 6-phospho-gluconate (6-P-G), no apparent stimulation of progestational steroid synthesis occurred. Specific activity measurements suggested that stimulation of synthesis was masked by increased conversion of progestational steroids to other products. When NADP and submaximal concentrations of LH were used together, potentiation rather than addition of effects on progesterone synthesis was found, and addition of effects with supramaximal concentrations of LH. No potentiation was found when NADP was replaced by NADP and G-6-P or 6-P-G, or by NADPH2. NADP, unlike LH, caused striking stimulation of progesterone synthesis by separated corpora lutea. It is suggested that the present results provide further support for the view that the actions of LH and NADP are related.

THE ENTRY OF ASCORBIC ACID INTO THE CORPUS LUTEUM IN VIVO AND IN VITRO AND THE EFFECT OF LUTEINIZING HORMONE

1967 ◽  
Vol 39 (1) ◽  
pp. 27-35 ◽  
Author(s):  
D. A. STANSFIELD ◽  
A. P. FLINT
Keyword(s):  
Ascorbic Acid ◽  
Exchange Rate ◽  
Luteinizing Hormone ◽  
Corpus Luteum ◽  
Plasma Ascorbic Acid ◽  
Progesterone Synthesis ◽  
Rat Ovary ◽  
Energy Dependent

SUMMARY Judged from the exchange rate between luteal and plasma ascorbic acid there appears to be no compartmentalization of ascorbic acid within the corpus luteum. Evidence is presented to show that the uptake of ascorbic acid into slices of superovulated rat ovary is an energy-dependent process which is inhibited by luteinizing hormone (LH) by means of its stimulatory effect on progesterone synthesis. The results are discussed in relation to the adrenal cortex and methods involving ascorbic acid depletion used in the assay of corticotrophin and LH.

STEROIDAL CONTROL OF THE RELEASE OF THE PREOVULATORY SURGE OF LUTEINIZING HORMONE IN THE RAT

1978 ◽  
Vol 79 (2) ◽  
pp. 223-234 ◽  
Author(s):  
CATHERINE A. WILSON ◽  
J. C. HADLEY ◽  
D. GILBERT ◽  
A. S. McNEILLY
Keyword(s):  
Plasma Concentration ◽  
Luteinizing Hormone ◽  
Critical Period ◽  
Adrenal Glands ◽  
Sham Operation ◽  
Late Afternoon ◽  
Immature Rats ◽  
Pregnant Mare Serum Gonadotrophin ◽  
Adrenalectomized Rats

Experiments were carried out on 4 day cyclic rats or immature rats induced to ovulate by administration of pregnant mare serum gonadotrophin. Removal of the ovaries and adrenal glands at 17.00 h of pro-oestrus, i.e. after the critical period, prevented the appearance of the surge of LH. Sham-operation or removal of only one of the sets of glands had no effect. This indicates that the preovulatory increase in the concentration of oestradiol is not solely responsible for the surge of LH; the presence of a steroid, secreted by the ovaries and adrenal glands in the late afternoon of pro-oestrus, is also required. Attempts were made to reinstate the surge of LH in ovariectomized, adrenalectomized rats by administration of one of the steroids normally secreted in late pro-oestrus. Corticosterone, 20α- and 20β-hydroxy-4-pregnen-3-one and 17α-hydroxyprogesterone all had no effect. Progesterone injected at the time of the operation stimulated the release of LH but only after the plasma concentration had reached its maximum 3–5 h after injection. Testosterone also stimulated the release of LH some hours after administration.

202 EFFECTS OF ASCORBIC ACID ON IN VITRO CULTURE OF CATTLE PREANTRAL FOLLICLES

2010 ◽  
Vol 22 (1) ◽  
pp. 259
Author(s):  
E. R. Andrade ◽  
R. van den Hurk ◽  
L. A. Lisboa ◽  
M. F. Hertel ◽  
F. A. Melo-Sterza ◽  
...  
Keyword(s):  
Ascorbic Acid ◽  
In Vitro Culture ◽  
Ovarian Tissue ◽  
Immunohistochemical Analysis ◽  
Development Stage ◽  
Nuclear Antigen ◽  
Primordial Follicles ◽  
Preantral Follicles ◽  
Ovarian Cortex

The mechanisms that regulate the gradual exit of ovarian follicles from the nongrowing, primordial pool are poorly understood. The objective of this study was to evaluate the effects of adding ascorbic acid to the media for in vitro culture of cattle ovarian fragments and to determine the effects of this addition on the growth activation and viability of preantral follicles. The ovarian cortex was divided into small fragments; 1 fragment was immediately fixed in Bouin’s solution (control). The other fragments were cultured for 2, 4, 6, or 8 days on culture plates in minimum essential medium (MEM) supplemented with insulin-transferrin-selenium (ITS), pyruvate, glutamine, hypoxantine, BSA, and antibiotics (MEM+) or in MEM+ plus ascorbic acid (5, 25, 50, 100, or 200 μg mL-1). Ovarian tissue was processed for classical histology, TEM, and immunohistochemical demonstration of proliferating cell nuclear antigen (PCNA). Preantral follicles were classified according to their development stage (primordial, intermediate, primary, and secondary) and on the basis of morphological features (normal or degenerated). Pair-wise comparisons were done using Tukey’s procedure. Chi-square test was used to compare percentages of follicles with PCNA-positive granulosa cells. All analyses were done with Statistical Analysis System (SAS Institute, Cary, NC, USA); P ≤ 0.05 was considered significant. Compared with control fragments, the percentage of primordial follicles was reduced (P ≤ 0.05) and the percentage of growing follicles was increased (P ≤ 0.05) in cultured cortical fragments, independent of the tested medium or incubation time. Furthermore, compared with control tissue, culture of ovarian cortex for 8 days reduced the percentages of healthy, viable follicles (P ≤0.05), but not when cultures were supplemented with 25, 50, and 100 μg mL-1 of ascorbic acid. Ultrastructural and immunohistochemical analysis of ovarian cortical fragments cultured for 8 days, however, showed the integrity and viability of follicles only when fragments were cultured in the presence of 50 μg mL-1 of ascorbic acid. In conclusion, this study demonstrated that addition of ascorbic acid to MEM at a concentration of 50 μg mL-1 not only stimulates the activation and subsequent growth of cattle primordial follicles that are cultured in vitro for 8 days but also safeguards the viability of these preantral follicles. E. R. Andrade and A. A. Alfieri are recipients of the PRODOC/CAPES fellowship.

STIMULATION BY β2-ADRENERGIC RECEPTORS OF THE PRODUCTION OF CYCLIC AMP AND PROGESTERONE IN RAT OVARIAN TISSUE

1980 ◽  
Vol 87 (1) ◽  
pp. 123-129 ◽  
Author(s):  
ALBERT RATNER ◽  
G. K. WEISS ◽  
CAROLYN R. SANBORN
Keyword(s):  
Cyclic Amp ◽  
Adrenergic Receptors ◽  
Ovarian Tissue ◽  
Chorionic Gonadotrophin ◽  
Human Chorionic Gonadotrophin ◽  
Adrenergic Stimulation ◽  
Immature Rats ◽  
Luteal Tissue ◽  
Pregnant Mare Serum Gonadotrophin ◽  
Stimulation Of

Ovarian tissue from immature rats treated with pregnant mare serum gonadotrophin (PMSG) or PMSG and human chorionic gonadotrophin was incubated in Medium 199. Stimulation of the formation of cyclic AMP in follicular and luteal tissue by terbutaline (10−5 mol/l), a selective β2-agonist, was blocked by butoxamine (10−5 mol/l), a selective β2-antagonist, whereas practolol (10−5 mol/l), a selective β1-antagonist, was ineffective. Propranolol (10−5 mol/l), a non-selective β-antagonist, butoxamine nor practolol affected the increase in cyclic AMP promoted by the addition of 1 μg LH. Stimulation of the production of progesterone in both follicular and luteal tissue by terbutaline was blocked by butoxamine, but not by practolol. These findings indicated that β-adrenergic stimulation of ovarian cyclic AMP and progesterone is mediated by β2-adrenergic receptors.

SOME OBSERVATIONS ON THE OVARIAN ASCORBIC ACID DEPLETION METHOD AS A TEST FOR LUTEINIZING HORMONE ACTIVITY

1962 ◽  
Vol 23 (4) ◽  
pp. 413-421 ◽  
Author(s):  
H. SCHMIDT-ELMENDORFF ◽  
J. A. LORAINE
Keyword(s):  
Ascorbic Acid ◽  
Luteinizing Hormone ◽  
Clinical Application ◽  
Sensitivity And Specificity ◽  
Chorionic Gonadotrophin ◽  
Human Chorionic Gonadotrophin ◽  
Assay Method ◽  
Hormone Activity ◽  
Low Degree ◽  
High Degree

SUMMARY The assay method for luteinizing hormone (LH) activity depending on ovarian ascorbic acid depletion in rats (O.A.A.D. method) has been assessed in terms of its reliability criteria. The chief advantages of the method are its high degree of sensitivity and specificity and its good practicability. Its disadvantages are its relatively low degree of precision and the fact that a proportion of assays are invalid due to lack of parallelism. The LH activity of various gonadotrophin preparations has been investigated using the O.A.A.D. method. The LH content of NIH-FSH and of Pergonal was found to be low. The LH activity of pregnant mare's serum gonadotrophin was lower than that of human chorionic gonadotrophin. When purified urinary extracts are used, the O.A.A.D. method is suitable for clinical application.

scholarly journals Effects of ascorbic acid on in vitro culture of bovine preantral follicles

Zygote ◽  
2012 ◽  
Vol 20 (4) ◽  
pp. 379-388 ◽  
Author(s):  
Evelyn R. Andrade ◽  
Robert van den Hurk ◽  
Lívia A. Lisboa ◽  
Mariana F. Hertel ◽  
Fabiana A. Melo-Sterza ◽  
...  
Keyword(s):  
Ascorbic Acid ◽  
Early Stage ◽  
Ovarian Tissue ◽  
Immunohistochemical Analysis ◽  
Nuclear Antigen ◽  
Primordial Follicles ◽  
Ovarian Cortex ◽  
Growth Activation ◽  
The Media

SummaryThe objective of this study was to evaluate the effects of adding ascorbic acid to the media for in vitro culture of cattle ovarian fragments and to determine their effects on growth activation and viability of early-stage follicles. The ovarian cortex was divided into small fragments; one fragment was immediately fixed (control) and the other fragments were cultured in minimum essential medium (MEM) supplemented or not with various doses of ascorbic acid. Ovarian tissue was processed for histology, transmission electron microscopy (TEM) and immunohistochemical demonstration of proliferating cell nuclear antigen (PCNA). Compared with control fragments, the percentage of primordial follicles was reduced (p < 0.05) and the percentage of growing follicles had increased (p < 0.05) in cultured cortical fragments, independent of the tested medium or incubation time. Furthermore, compared with control tissue, culture of ovarian cortex for 8 days reduced the percentages of healthy, viable follicles (p < 0.05), but not when cultures were supplemented with 25, 50 or 100 μg/ml of ascorbic acid. Ultrastructural and immunohistochemical analysis of 8 day cultured ovarian cortical fragments, however, showed the integrity and viability of follicles only when fragments were cultured in presence of 50 μg/ml of ascorbic acid. In conclusion, this study demonstrated that addition of ascorbic acid to MEM at a concentration of 50 μg/ml not only stimulates the activation of 8 day in vitro cultured cattle primordial follicles and subsequent growth of activated follicles, but also safeguards the viability of these early-stage follicles.

Heterogeneity in the luteal population following superovulation with pregnant mare serum gonadotrophin and human chorionic gonadotrophin in the sheep

1989 ◽  
Vol 121 (3) ◽  
pp. 459-465 ◽  
Author(s):  
M. G. Hunter ◽  
J. A. Southee
Keyword(s):  
Luteal Phase ◽  
Human Chorionic Gonadotrophin ◽  
Corpora Lutea ◽  
Plasma Progesterone ◽  
Progesterone Synthesis ◽  
Luteal Tissue ◽  
The Individual ◽  
Effect Of Age ◽  
Pregnant Mare Serum Gonadotrophin

ABSTRACT In order to investigate the development and possible heterogeneity in the luteal population following superovulation, anoestrous ewes were induced to ovulate using progestagen priming followed by injections of pregnant mare serum gonadotrophin (1000 IU) and hCG (1000 IU). Ovaries were recovered from ewes on each of days 2, 4, 6, 8, 10, 12 and 15, and the weight, progesterone content, 125I-labelled hCG binding and progesterone synthesis in vitro of the individual corpora lutea measured. The results obtained showed that plasma progesterone concentrations on the day of slaughter were significantly correlated with time (P<0·05), total weight of luteal tissue (P< 0·001) and number of corpora lutea (P<0·05). The number of corpora lutea recovered per animal ranged from two to 12 and was significantly (P<0·05) correlated with the day after hCG injection until day 10. There was much variation between individual corpora lutea, particularly in terms of weight and progesterone content, although both were significantly (P<0·001) correlated with day of recovery until day 10. 125I-Labelled hCG binding was significantly (P<0·001) correlated with time until day 15. There was a significant (P<0·001) effect of age of the tissue on progesterone production in vitro, with output declining throughout the luteal phase. These results show that the number of corpora lutea induced by superovulation in anoestrous ewes was very variable, and suggest that ovulation may have continued to occur during the luteal phase. Moreover, there was much variation between individual corpora lutea recovered from the same animal, and thus it should not be assumed that an individual corpus luteum is representative of the entire population. Journal of Endocrinology (1989) 121, 459–465

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