Comparison of Induced Corpora Lutea from Prepuberal Gilts and Spontaneous Corpora Lutea from Mature Gilts: In Vitro Progesterone Production1

Kineman, Rhonda D; Rampacek, George B.; Kraeling, Robert R.; Fiorello-Stocks, N. A.; Wilson, R. L.

doi:10.2527/jas1987.642526x

Cited by 11 publications

(6 citation statements)

References 14 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Results from dispersed monolayers of luteal cells in culture indicate that prolactin and LH increase the rates of relaxin and progesterone secretion (Grinwich et al, 1983;Huang et al, 1991). Porcine luteal cells have prolactin-specific binding receptors (Rolland et al, 1976;Bramley & Menzies, 1987) and LH can stimulate progesterone secretion by these cells from the oestrous cycle and early pregnancy (Lemon & Loir, 1977;Hunter, 1981;Kineman & Rampacek, 1987), which is consistent with the present findings with ageing corpora lutea.…”

Section: Discussionsupporting

confidence: 80%

Synergistic effects of insulin-like growth factor I and gonadotrophins on relaxin and progesterone secretion by ageing corpora lutea of pigs

Huang¹,

Li²,

Stromer³

et al. 1992

Reproduction

View full text Add to dashboard Cite

Summary. Insulin-like growth factor I (IGF-I) is involved in paracrine/autocrine regulation of gonadal steroidogenesis and peptide hormone biosynthesis. This study was designed to determine whether IGF-I alone, or an interaction of IGF-I, is involved in augmenting the actions of luteinizing hormone (LH) and prolactin in controlling relaxin and progesterone secretion from ageing corpora lutea of hysterectomized gilts at days 110, 113 and 116 after oestrus. Luteal tissue slices were incubated for 8 h with IGF-I (0, 50, 300 ng ml \ m=-\ 1) , LH (0, 100, 1000 ng ml \ m=-\ 1), and prolactin (0, 100, 1000 ng ml \ m=-\ 1) alone or in combination. Progesterone and relaxin concentrations were determined by radioimmunoassay of spent medium and of homogenates from luteal tissue slices before and after incubation. Porcine luteal tissue from day 110 had a net output of 25 ng progesterone and 26 ng relaxin in the control and of 65 ng progesterone and 2125 ng relaxin in the combined IGF-I, LH and prolactin treatment mg\m=-\1 of luteal tissue, respectively. IGF-I, LH and prolactin alone or in combination significantly increased (P<0\m=.\01) progesterone production by luteal tissue from day 110, but they were partially effective at day 113 and ineffective at day 116. By contrast, the same hormone treatments increased relaxin production by luteal tissue from days 110 and 113. Even at day 116, prolactin alone or with LH or IGF-I continued to stimulate relaxin production. In conclusion, IGF-I augments the ability of prolactin and LH to increase relaxin production by ageing corpora lutea; however, a decrease in progesterone secretion and an increase in relaxin secretion at day 113 indicate that different mechanisms control progesterone and relaxin secretion in pigs.

show abstract

Section: Discussionsupporting

confidence: 80%

Synergistic effects of insulin-like growth factor I and gonadotrophins on relaxin and progesterone secretion by ageing corpora lutea of pigs

Huang¹,

Li²,

Stromer³

et al. 1992

Reproduction

View full text Add to dashboard Cite

show abstract

“…Earlier studies of Kineman et al. (,b) compared steroidogenic enzyme system in CLs of prepubertal gilts induced to ovulate and spontaneous CL of mature gilts (after one or more oestrous cycles). Interestingly, 3 β HSD activity tended to increase in CLs collected from gonadotropin‐treated prepubertal gilts (Kineman et al.…”

Section: Discussionmentioning

confidence: 99%

“…P4 regulates the expression of several genes important for embryo-maternal interactions (for review see Spencer et al 2004;Ziecik et al 2011). Pharmacological manipulations to synchronize oestrus in domestic animals may cause decreased level of P4 in blood serum, which results from impaired luteal P4 metabolic pathway (Kineman et al 1987a) and reduced sensitivity to gonadotropic stimulation (Kineman et al 1987b;Skarzynski et al 2009). Low concentrations of circulating P4 altered the expression of endometrial genes that potentially contribute to histotroph composition and conceptus elongation in cattle (Forde et al 2011(Forde et al , 2012.…”

Section: Introductionmentioning

confidence: 99%

Effect of Oestrus Synchronization with PGF2α/eCG/hCG on Luteal P4 Synthesis in Early Pregnant Gilts

Szymańska

Morawska-Pucinska

Krawczynski

et al. 2014

Reprod Domestic Animals

View full text Add to dashboard Cite

Administration of hormones to synchronize oestrus is a useful tool in animal breeding. However, exogenous ovarian stimulation may be detrimental to reproductive function. This study was aimed to examine whether an oestrus synchronization with PGF2α/eCG/hCG could affect luteal P4 synthesis in early pregnant gilts. Corpora lutea (CLs) were collected on days 9, 12 and 16 of pregnancy from gilts with natural (n = 16) and synchronized (n = 18) oestrus and analysed for (i) the expre-ssion of steroidogenic acute regulatory protein (StAR), cytochrome P450 family 11 subfamily A polypeptide (CYP11A1), and 3β-hydroxysteroid dehydrogenase (3βHSD); (ii) the concentration of P4 in the luteal tissue and blood; and (iii) the expression of luteinizing hormone receptors (LHR) and oestrogen receptors (ERα and ERβ). Additionally, the effect of LH on P4 secretion from CL slices collected from synchronized and naturally ovulated animals has been studied in vitro. PGF2α /eCG/hCG administration increased mRNA expression of StAR, CYP11A1, 3βHSD, and LHR on day 9 and CYP11A1 and LHR on day 12 of pregnancy compared with the control group (p < 0.05). CYP11A1, 3βHSD, LHR, ERα and ERβ proteins were not affected by synchronization; only StAR protein increased in hormonally treated animals (p = 0.017). The concentration of P4 in luteal tissue was greater on day 9 (p < 0.01), but lower on day 16 (p < 0.05) in gilts with hormonally induced oestrus compared with control animals. Blood serum levels of P4 were lower in synchronized than control gilts (p < 0.001). Synchronization did not affect LH-stimulated P4 secretion from luteal slices; however, greater basal concentration of P4 in incubation medium was detected for CLs collected from synchronized than control gilts (p < 0.05). In conclusion, synchronization of oestrus with PGF2α/eCG/hCG protocol in gilts did not impair the expression of luteal P4 synthesis system, although decreased P4 concentration in the blood.

show abstract

“…However, the ratio of protein: DNA decreased slightly, though significantly, in both groups up to day 12 suggesting that the size of cells in CL had on average actually decreased (Baserga, 1985). Kineman et al (1987) observed no change in the proportion of large luteal cells per CL in dispersed cell preparations from hysterectomized pigs between day 10 and day 14. In view of the low mitotic rate of porcine lutein cells and the decrease in the ratio of luteal protein: DNA content it seems most likely that the increase in DNA content or cell numbers in the present study was due to increases in the number of smaller, nonsteroidogenic elements.…”

Section: Discussionmentioning

confidence: 69%

“…No evidence was presented to verify that the cell membrane antigenic components did not also change through the estrous cycle in either cell population however, and the identity of the proteins labelled by the antibodies was not recognized so that the expected specificty of each of the components could not be confirmed. In the pig, Kineman et al (1987) also presented data on large and small dispersed cell populations from CL collected from gilts at various times throughout the estrous cycle. These data also suggested that large luteal cells were more numerous during the later stages of the luteal phase.…”

Section: Morphology and Developmentmentioning

confidence: 99%

Aspects of luteal function in pigs and sheep

Conley¹

View full text Add to dashboard Cite

Previous studies have demonstrated that estradiol-17p (E2) locally increases corpus luteum (CL) wt in pigs, suggesting a direct luteotropiceffect. This study examined the effect of intraluteal Eg implants on utero-ovarian vein (UOV) progesterone (P4), E2, PGF2a and CL wt in cyclic gilts. Eight gilts were laparotomized on day II (day 0 = first day of estrus), catheters were placed in both UOV and gilts were then divided into 2 equal groups (E2-treated and controls). Each CL on one ovary of E2-treated gilts was injected with a quick curing silastic implant containing E2 while each CL on the contralateral ovary received a vehicle implant. Control gilts received bilateral vehicle implants. Blood was collected at 10 min intervals for 1 hour beginning at 0600 and 1800 h from day 11 today 18. Gilts were ovariectomized on day 19. Corpora lutea were weighed, homogenized and assayed for P4. Utero-ovarian venous plasma was assayed for P4, E2, and PGF2a by validated RIA. No side differences were observed in CL wt or UOV P4 within groups. CL were maintained in E2-treated, but not control gilts as evidenced byCLwt{333 ± 20vs 154 ± 12mg),CLP4content(21.8 ± 2.1 vs.3 ± .1g), and CL P4 concentration (65.7 ± 5.5 vs 2.3 ± .6ng/mg), respectively. Uteroovarian venous P4 values were similar between groups up to 1800 h on d 15, declining from 346 ± 122ng/ml at 1800 hour on day 11 to 147 ± 20ng/ml on day 12, then remaining constant to 1800 hour on day 15. Thereafter UOV P4in E2treated gilts returned progressively today 11 values by 1800 hour on day 18 (364 ± 97ng/ml) while values of control gilts declined to low levels (5.4 ± .6ng/ml). In E2-treated gilts in UOV plasma E2 was elevated 13 fold ipsilateral, and 4 fold contralateral, to the E2-treated ovary in comparison to levels in control gilts. Uterine PGF2a release was suppressed in E2-treated compared to control gilts. E2 (yg quantities) failed to prevent the initial decline in UOV P4 between day 11 and day 15, but subsequently returned CL function to normal, as evidenced by increasing UOV P4, through day 18.

show abstract

Comparison of Induced Corpora Lutea from Prepuberal Gilts and Spontaneous Corpora Lutea from Mature Gilts: In Vitro Progesterone Production1

Cited by 11 publications

References 14 publications

Synergistic effects of insulin-like growth factor I and gonadotrophins on relaxin and progesterone secretion by ageing corpora lutea of pigs

Synergistic effects of insulin-like growth factor I and gonadotrophins on relaxin and progesterone secretion by ageing corpora lutea of pigs

Effect of Oestrus Synchronization with PGF2α/eCG/hCG on Luteal P4 Synthesis in Early Pregnant Gilts

Aspects of luteal function in pigs and sheep

Contact Info

Product

Resources

About