OVULATION AND CORPUS LUTEUM FUNCTION IN THE LLAMA (LAMA GLAMA)

1969 ◽  
Vol 45 (4) ◽  
pp. 505-513 ◽  
Author(s):  
B. G. ENGLAND ◽  
W. C. FOOTE ◽  
D. H. MATTHEWS ◽  
ARMANDO G. CARDOZO ◽  
S. RIERA
Keyword(s):  
Luteinizing Hormone ◽  
Corpus Luteum ◽  
Breeding Season ◽  
Luteal Phase ◽  
Maximum Size ◽  
Chorionic Gonadotrophin ◽  
Human Chorionic Gonadotrophin ◽  
Corpora Lutea ◽  
Lama Glama

SUMMARY Results in 53 llamas (33 mated animals and 20 controls) showed that ovulation is copulation-induced in this species. Ovulation without copulation occasionally occurred during the height of the recognized breeding season in Bolivia. The first mating during the luteal phase (12–24 days after the preceding ovulation) resulted in ovulation in four out of ten llamas. Determination of pituitary luteinizing hormone (LH) content showed the highest level on the day before mating (9·00 μg./mg.) and the lowest level on day 4 (6·25 μg./mg.). LH level on day 8 was significantly higher than on day 4 (7·62 μg./mg.). Corpora lutea (c.l.) were well formed on day 4 after mating (408 mg.), reached a maximum size by day 8 (1920 mg.) and rapidly decreased in size to day 16 (136 mg.). The corpus albicans remained as an entity but decreased in size to 21 mg. on day 120. Similar changes were found in c.l. histology and progesterone content. The combined results indicate that the functional life of the c.l. in a non-pregnant llama is 16 days or less. Treatment with 25 i.u. human chorionic gonadotrophin was sufficient to cause ovulation in 50% of the animals treated. A large (150 mg.) dose of norethandrolone did not cause morphological regression of the c.l. when measured 5 days after treatment. Treatment with 5 mg. daily for 14 days caused regression of c.l. as compared with untreated controls and animals treated with oestradiol valerate.

CHANGES IN THE BINDING OF HUMAN CHORIONIC GONADOTROPHIN/LUTEINIZING HORMONE, FOLLICLE-STIMULATING HORMONE AND PROLACTIN TO HUMAN CORPORA LUTEA DURING THE MENSTRUAL CYCLE AND PREGNANCY

1980 ◽  
Vol 87 (3) ◽  
pp. 315-325 ◽  
Author(s):  
A. S. McNEILLY ◽  
J. KERIN ◽  
I. A. SWANSTON ◽  
T. A. BRAMLEY ◽  
D. T. BAIRD
Keyword(s):  
Menstrual Cycle ◽  
Luteinizing Hormone ◽  
Luteal Phase ◽  
Follicle Stimulating Hormone ◽  
Chorionic Gonadotrophin ◽  
Human Chorionic Gonadotrophin ◽  
Corpora Lutea ◽  
Maximum Serum ◽  
Human Menstrual Cycle ◽  
Stimulating Hormone

The changes in the binding of human chorionic gonadotrophin/luteinizing hormone (HCG/LH), follicle-stimulating hormone (FSH) and prolactin to 44 corpora lutea have been assessed during the luteal phase of the human menstrual cycle and early pregnancy. All corpora lutea bound HCG but out of 32 only ten bound FSH and only seven bound prolactin specifically. While binding of HCG increased to maximal levels in the mid-luteal phase, binding of FSH and prolactin was most often found in the early luteal phase. Maximum binding of HCG was associated with maximum serum levels of progesterone. Luteal regression was associated with a decrease in the binding of HCG but a causal relationship could not be established. Very low binding of HCG was found to corpora lutea of pregnancy. These results show that (1) the changes in binding of HCG during the luteal phase of the human menstrual cycle are similar to those in other species and (2) there are specific binding sites for prolactin and FSH in the human corpus luteum.

Prolactin stimulates steroidogenesis by human luteal tissue in vitro

1984 ◽  
Vol 103 (1) ◽  
pp. 107-110 ◽  
Author(s):  
M. G. Hunter
Keyword(s):  
Corpus Luteum ◽  
Luteal Phase ◽  
Chorionic Gonadotrophin ◽  
Human Chorionic Gonadotrophin ◽  
Corpora Lutea ◽  
Progesterone Production ◽  
Luteal Tissue ◽  
Oestradiol Production ◽  
Human Corpus Luteum

ABSTRACT Human luteal tissue recovered from varying stages of the luteal phase was minced and incubated for 3 h and the effect of human chorionic gonadotrophin (hCG), prolactin and hCG + prolactin on progesterone and oestradiol production measured. While hCG generally enhanced both progesterone and oestradiol synthesis, prolactin alone at either 20 or 200 μg/l had no significant effect on steroidogenesis. When prolactin was added along with hCG in four of six corpora lutea, however, progesterone production significantly increased and in three of six corpora lutea oestradiol production was increased above that induced by hCG alone. It is concluded that prolactin may play some role in the control of steroidogenesis by the human corpus luteum. J. Endocr. (1984) 103, 107–110

STIMULATION BY HUMAN CHORIONIC GONADOTROPHIN OF OESTRADIOL PRODUCTION BY DISPERSED CELLS FROM HUMAN CORPUS LUTEUM: COMPARISON WITH PROGESTERONE PRODUCTION; UTILIZATION OF EXOGENOUS TESTOSTERONE

1981 ◽  
Vol 91 (2) ◽  
pp. 197-203 ◽  
Author(s):  
M. C. RICHARDSON ◽  
G. M. MASSON
Keyword(s):  
Luteal Phase ◽  
Chorionic Gonadotrophin ◽  
Human Chorionic Gonadotrophin ◽  
Cell Suspensions ◽  
Corpora Lutea ◽  
Progesterone Production ◽  
Late Luteal Phase ◽  
Oestradiol Production ◽  
Dispersed Cells

Cell suspensions were prepared from tissue samples of human corpora lutea obtained during the mid- and late-luteal phase of the menstrual cycle. Both oestradiol and progesterone production by dispersed cells were stimulated by similar concentrations of human chorionic gonadotrophin (hCG). As the degree of stimulation of production by hCG was greater for progesterone than for oestradiol (five- to tenfold compared with two- to threefold higher than basal production), the ratio of progesterone to oestradiol produced varied according to the level of trophic stimulation. A comparison of cell suspensions prepared from mid- and late-luteal phase corpora lutea, exposed to the same concentration of hCG (10 i.u./ml) in vitro, did not reveal a shift to oestradiol production in the late-luteal phase. Provision of additional testosterone during incubation raised the level of oestradiol production by dispersed luteal cells. At an optimum concentration of testosterone (1 μmol/l), oestradiol synthesis was not raised further in the presence of hCG or N6, O2-dibutyryl cyclic AMP, suggesting a lack of induction or activation of the aromatase system by gonadotrophin in short-term cultures. Basal and stimulated levels of progesterone production were not significantly impaired in the presence of testosterone.

Oxytocin may play a role in the control of the human corpus luteum

1982 ◽  
Vol 95 (1) ◽  
pp. 65-70 ◽  
Author(s):  
G. J. S. Tan ◽  
R. Tweedale ◽  
J. S. G. Biggs
Keyword(s):  
Menstrual Cycle ◽  
Corpus Luteum ◽  
Inhibitory Action ◽  
Chorionic Gonadotrophin ◽  
Human Chorionic Gonadotrophin ◽  
Corpora Lutea ◽  
Luteal Cells ◽  
Progesterone Production ◽  
Human Corpus Luteum

The effects of oxytocin on dispersed luteal cells from human corpora lutea of the menstrual cycle were studied. Oxytocin at a concentration of 4 mi.u./ml produced a slight increase in basal progesterone production. However, higher oxytocin concentrations (400 and 800 mi.u./ml) markedly inhibited both basal and human chorionic gonadotrophin-induced progesterone production. These data provide evidence for an effect of oxytocin on the human corpus luteum. In view of the inhibitory action of oxytocin, increased secretion of this hormone may be important in the demise of the corpus luteum at the end of the menstrual cycle.

IMMUNOLOGICAL DETERMINATION OF PITUITARY LUTEINIZING HORMONE IN THE URINE OF FERTILE AND POST-MENOPAUSAL WOMEN AND ADULT MEN

1962 ◽  
Vol 39 (4) ◽  
pp. 539-546 ◽  
Author(s):  
Leif Wide ◽  
Carl Gemzell
Keyword(s):  
Luteinizing Hormone ◽  
Haemagglutination Inhibition ◽  
Chorionic Gonadotrophin ◽  
Human Chorionic Gonadotrophin ◽  
Human Pituitary ◽  
Adult Men ◽  
Menopausal Women ◽  
Post Menopausal ◽  
Inhibition Reaction

ABSTRACT An immunological method to assay human pituitary luteinizing hormone (HPLH) in urine is described. It is based on the fact that HPLH crossreacts with human chorionic gonadotrophin (HCG) in an haemagglutination inhibition reaction between HCG-coated blood cells and rabbit HCG-antisera. During the menstrual cycle the excretion of HPLH reached a peak of 200–400 U per liter at the time of ovulation. In the urine of post-menopausal women the concentration of HPLH was between 100 and 400 U per liter. In the urine of adult men the concentration of HPLH was between 50 and 160 U per liter.

103 Effects of administration of human chorionic gonadotrophin at Day 5 post-ovulation on development of the original corpus luteum depend on the locational relationship between the original and accessory corpora lutea

2020 ◽  
Vol 32 (2) ◽  
pp. 177
Author(s):  
K. Hazano ◽  
S. Haneda ◽  
M. Matsui
Keyword(s):  
Corpus Luteum ◽  
Repeated Measures ◽  
Chorionic Gonadotrophin ◽  
Human Chorionic Gonadotrophin ◽  
Corpora Lutea ◽  
Intrauterine Environment ◽  
Prostaglandin F2a ◽  
Tissue Area ◽  
Luteal Tissue ◽  
Relationship Of

In cattle, human chorionic gonadotrophin (hCG) is administered at Day 5 post-ovulation to improve fertility. This treatment can induce ovulation of the first-wave dominant follicle (W1DF), from which an accessory corpus luteum (CL) is generated. In addition, hCG has the effect of promoting CL development. It is possible that the locational relationship between the original and accessary CLs influences the effect of hCG on CL development, because the locational relationship of the CLs affects intraovarian blood flow. The present study aimed to clarify whether the locational relationship between the original and accessory CLs influences the effect of hCG on their development. Cross-bred beef heifers (Holstein×Japanese Black, n=56) were used for the present study. The oestrus cycle was synchronized using oestradiol benzoate (EB) and a controlled internal drug release (CIDR)-based program. Briefly, an administration of EB (2mg) with 9-day CIDR insertion was followed by administration of prostaglandin F2a analogue (PGF2a) on the day of CIDR removal, EB (1mg) 1 day after a PGF2a injection, and GnRH 12h after the second EB injection. At Day 5 post-ovulation, the locational relationship between the original CL and the W1DF was confirmed using transrectal ultrasonography (USG), and two groups were defined: ipsilateral group (IG; n=30), in which the CL and the W1DF are in the same ovary, and contralateral group (CG; n=26), in which the CL and the W1DF are in separate ovaries. Moreover, IG and CG were respectively subdivided into two groups, with or without hCG (1500IU) treatment (IG/hCG, n=15; IG without hCG, n=15, and CG/hCG, n=14; CG without hCG, n=12). The diameter and luteal tissue area (i.e. minus the cavity area) of the original CL and the accessory CL were examined at Days 5, 7, and 14, using USG. Two-way repeated-measures ANOVA was used to compare the diameter and luteal tissue area between IG/hCG and IG without hCG, and between CG/hCG and CG without hCG. In CG, the diameter (P<0.01) and luteal tissue area of the original CL (P<0.001) at Day 7 was increased by receiving hCG, while it did not change in IG. The diameter and luteal tissue area of the original CL at Day 14 were not affected by the administration of hCG in either CG or IG. Moreover, for the accessory CL, no difference of the diameter and luteal tissue area was observed between CG and IG. The present study showed that hCG treatment at Day 5 post-ovulation stimulate the growth of the original CL at Day 7, when the original CL and accessory CL are on contralateral sides. Our results suggest that the effect of administration of the hCG at Day 5 post-ovulation on the original CL development depends on the locational relationship between the original and accessory CL (IG or CG). The function of the CL affects the intrauterine environment for embryonic development. Therefore, it is necessary to investigate the effect of the hCG injection at Day 5 on the function of CL (i.e. plasma P4 concentration) in IG and CG, respectively.

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.

DIFFERENTIAL PROPERTIES OF HUMAN CHORIONIC GONADOTROPHIN AND HUMAN LUTEINIZING HORMONE BINDING TO PLASMA MEMBRANES OF BOVINE CORPORA LUTEA

1979 ◽  
Vol 90 (4) ◽  
pp. 696-710 ◽  
Author(s):  
Ch. V. Rao
Keyword(s):  
Luteinizing Hormone ◽  
Plasma Membranes ◽  
Chorionic Gonadotrophin ◽  
Human Chorionic Gonadotrophin ◽  
Corpora Lutea ◽  
Lower Affinity ◽  
Receptor Sites ◽  
Common Receptor ◽  
Triton X ◽  
Differential Properties

ABSTRACT Plasma membranes of bovine corpora lutea contain common receptor sites for [125I] human chorionic gonadotrophin (hCG) and [125I] human luteinizing hormone (hLH) to which hLH binds with 4-fold lower affinity than hCG. The presence of additional sites for hLH was indicated by the lack of saturation of [125I]hLH binding as compared to [125I]hCG and lower degree of inhibition of binding by 830 pm of unlabelled hCG, when [125I]-hLH instead of [125I]hCG was used. Differences in [125I]hCG and [125I]-hLH binding were observed by exposing receptors to increasing temperatures and pHs and by pre-treating membranes with dimethyl sulphoxide, Triton X-100, various enzymes and protein reagents. The above differences can only be reconciled by differential responses of common hCG-hLH sites and additional sites for hLH.

Steroid concentrations in rat corpora lutea isolated during the oestrous cycle and pseudopregnancy: effect of induction of ovulation at dioestrus

1989 ◽  
Vol 120 (2) ◽  
pp. 325-330 ◽  
Author(s):  
J. Th. J. Uilenbroek ◽  
P. J. A. Woutersen ◽  
P. D. M. van der Vaart
Keyword(s):  
Pituitary Gland ◽  
Corpus Luteum ◽  
Chorionic Gonadotrophin ◽  
Human Chorionic Gonadotrophin ◽  
Oestrous Cycle ◽  
Corpora Lutea ◽  
Serum Concentrations ◽  
Kidney Capsule ◽  
Cervical Stimulation ◽  
Sensitive Method

ABSTRACT Corpora lutea could be identified under the dissection microscope up to 7 days after formation. They were isolated during the oestrous cycle and pseudopregnancy and the progesterone and 20α-OH-progesterone contents were compared with serum values of these steroids. The pattern of progesterone in serum resembled that found in the corpora lutea. However, the pattern of 20α-OH-progesterone concentrations in serum and corpora lutea were different. While 20α-OH-progesterone concentrations in the corpora lutea showed large variations during the cycle, changes in serum concentrations of 20α-OH-progesterone were relatively small. Measurement of hormone concentrations in isolated corpora lutea is therefore a sensitive method for studying corpus luteum activity. To study whether corpora lutea derived after ovulation of immature follicles showed deficient luteal activity, rats at dioestrus (2 days before pro-oestrus) were induced to ovulate by the injection of 10 IU human chorionic gonadotrophin (hCG) and subsequent luteal activity was studied by measuring hormone concentrations in the corpora lutea on day 5 of pseudopregnancy. Concentrations of progesterone, but not of 20α-OH-progesterone, in corpora lutea derived from follicles induced to ovulate at dioestrusday 1 were significantly lower than those in corpora lutea derived from follicles induced to ovulate at prooestrus. This difference was observed not only when pseudopregnancy was induced by cervical stimulation but also when it was induced by implantation of a pituitary gland under the kidney capsule. However, in the latter case, corpora lutea already present on the day of hCG injection also became activated. The present experiments demonstrate that by measuring hormone concentrations in isolated corpora lutea changes in luteal activity can be studied effectively. Moreover, it appears that corpora lutea derived from immature follicles contained less progesterone than those derived from fully mature follicles. Journal of Endocrinology (1989) 120, 325–330

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