Effects of porcine relaxin on induced parturition in beef heifers

Smith, Donald E.; Hixon, D. L.; Moore, D.W.; Kirk, Edward A. Van; Alexander, Brenda M.; Anthony, Russell V.; Moss, G. E.

doi:10.1016/s0739-7240(96)00089-6

Cited by 6 publications

(3 citation statements)

References 27 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Thus, it was suggested that in ruminants, other members of the RLN/INSL family or non-relaxin ligands could compensate for the missing RLN1 (Dai et al, 2017;Malone et al, 2017). However, studies to validate the concept of a relaxin physiology in ruminants by applying porcine relaxin to late pregnant heifers yielded inconsistent results (Musah et al, 1986;Bagna et al, 1991;Smith et al, 1996Smith et al, , 1997 and these studies did not investigate transcytosis mechanisms. The closest related peptide to that of RLN is INSL3.…”

Section: Potential Placental Signaling Affecting Colostrum Productionmentioning

confidence: 99%

Endocrine changes during the peripartal period related to colostrogenesis in mammalian species

Bigler

Gross

Baumrucker

et al. 2023

Journal of Animal Science

View full text Add to dashboard Cite

This review discusses endocrine and functional changes during the transition from late gestation to lactation that are related to the production of colostrum in different mammalian species. Species covered in this article include ungulate species (cattle, sheep, goats, pigs, horses), rodents (rat, mouse), rabbits and carnivores (cats, dogs), as well as humans. An immediate availability of high quality colostrum for the newborn after birth is crucial in species where a transfer of immunoglobulins (Ig) does not or only partially occur via the placenta during pregnancy. Declining activity of gestagens, in most species progesterone (P4), is crucial at the end of pregnancy to allow for the characteristic endocrine changes to initiate parturition and lactation, but the endocrine regulation of colostrogenesis is negligible. Both, the functional pathways and the timing of gestagen withdrawal differ considerably among mammalian species. In species with a sustaining corpus luteum (CL) throughout the entire pregnancy (cattle, goat, pig, cat, dog, rabbit, mouse and rat), a prostaglandin F2α(PGF2α)-induced luteolysis shortly before parturition is assumed to be the key event to initiate parturition as well as lactogenesis. In species where the gestagen production is taken over by the placenta during the course of gestation (e.g. sheep, horse and human), the reduction of gestagen activity is more complex, as PGF2α-does not affect placental gestagen production. In sheep the steroid hormone synthesis is directed away from P4 towards estradiol-17β (E2) to achieve a low gestagen activity at high E2 concentrations. In humans the uterus becomes insensitive to P4, as parturition occurs despite still high P4 concentrations. However, lactogenesis is not completed as long as P4 concentration is high. Early colostrum and thus Ig intake for immune protection is not needed for the human newborn which allows a delayed onset of copious milk secretion for days until the placenta expulsion causes the P4 drop. Like humans, horses do not need low gestagen concentrations for successful parturition. However, newborn foals need immediate immune protection through Ig intake with colostrum. This requires the start of lactogenesis before parturition which is not fully clarified. The knowledge of the endocrine changes and related pathways to control the key events integrating the processes of colostrogenesis, parturition, and start of lactation are incomplete in many species.

show abstract

Section: Potential Placental Signaling Affecting Colostrum Productionmentioning

confidence: 99%

Endocrine changes during the peripartal period related to colostrogenesis in mammalian species

Bigler

Gross

Baumrucker

et al. 2023

Journal of Animal Science

View full text Add to dashboard Cite

show abstract

“…Thus, it was suggested that in ruminants other members of the RLN/INSL family or non-relaxin ligands could compensate for the missing RLN1 ( Dai et al ., 2017 ; Malone et al ., 2017 ). However, studies to corroborate the concept of a relaxin physiology in ruminants applying porcine relaxin to late pregnant heifers yielded inconsistent results ( Musah et al ., 1986 ; Bagna et al ., 1991 ; Smith et al ., 1996 , 1997 ).…”

Section: The Placenta As An Endocrine Organ During Pregnancymentioning

confidence: 99%

Placental contribution to the endocrinology of gestation and parturition

Schuler¹,

Fürbaß²,

Klisch

2018

Anim Reprod

View full text Add to dashboard Cite

In addition to many other functions, the placenta is a source of a vast number of autocrine, paracrine and endocrine factors. However, the spectrum of placental regulatory factors, their concentrations, gestational profiles and roles may differ considerably even between phylogenetically closely related species. Depending on the species, placental regulatory factors of a broad range of molecule classes have been found including (glyco-)proteins, peptides, steroids and prostaglandins. Local placental regulatory factors are especially important for the dialogue between the fetal and the maternal compartment immediately at the feto-maternal borderline and for the control of growth, differentiation and functions of the placenta itself. Moreover, placental hormones in a proper sense may also have effects in more remote targets within the maternal compartment, serving functions such as pregnancy-specific adaptations of maternal circulation, provision of hemotrophe to the fetus or the development and function of the mammary gland. Functions of placental hormones in the fetus proper are less clear but may be especially important before the establishment of a functional fetal endocrine system and near term within the highly species-specific networks of signals preparing and initiating parturition. This review takes a comparative view on the situation in different domestic animals focusing on ruminants and on placental hormones occurring at significant concentrations in the maternal circulation.

show abstract

“…However, almost all length of pregnancy needs uterine quiescence [24,25]. It is reached by progesterone (P4) block of oxytocin (OT) receptors in the myometrium, [26] and relaxin (RLX), which directly inhibit the uterine contractions, as well it is involved in cervical dilation and relaxation of pubic symphysis [27]. Moreover, RLX induced suppression of OT release from corpus luteum in cow [28].…”

mentioning

confidence: 99%

The Preliminary Study About the Involvement of Relaxine in Adverse Effect of Polychlorinated Biphenyls on Bovine Myometrial Contractions

Wróbel¹

2017

J Clin Mol Endocrinol

View full text Add to dashboard Cite

Polychlorinated biphenyls (PCBs) are a group of synthetic xenobiotics, which were used in lots of industrial applications. Two individual congers (PCB 153 and PCB 77) belong to the most prominent environmental contaminations among PCBs, but they have opposite type of configuration and therefore they can exert a different way of action. Since PCBs increased the force of myometrial contractions, in this work, their effect on myometrial sensitivity on inhibitor of myometrial contractions (relaxine, RLX) was studied.Bovine myometrial cells and strips, and luteal cell at 4-8 month of pregnancy, were obtained accidentally in commercial abattoir. They were treated by PCB 153 and PCB 77 and mRNA expression of RLX receptor in myometrial cells and contractions of myometrial strips as well as the secretion of progesterone (P4) and oxytocin (OT) from luteal cells, were measured under their effect.Both studied congeners decreased (P<0.05) the mRNA expression of RLX receptor in myometrium. Admittedly, both PCB 77 and 153 increased (P<0.05) the basal force of contractions, while RLX showed any effect on myometrial contractions. Studied PCBs increased also (P<0.05) secretion of P4 and OT from luteal cells.It is suggested that PCBs can decreased the sensitivity of myometrium on RLX but their direct effect on RLX function have to be further investigated. Keywords: Endocrine Disruption; Pregnancy; Uterus IntroductionPolychlorinated biphenyls (PCBs) are a group of synthetic, chlorinated aryl hydrocarbons, which were extensively used in lots of industrial applications, mainly in transformers, capacitors or as hydraulic fluids, heat exchange liquids as well as plasticizers and others [1]. Because of different degree of chlorination, there are possible up to 209 congeners of PCBs. Among them, 3,3 ' ,4,4 ' -tetrachlorobiphenyl (PCB 77) is one of the most abundant PCB congeners in human milk. This congener is a non-ortho chlorine substituted with coplanar configuration and appear to exert its toxic effects via interacting with the cytosolic aryl hydrocarbon receptor (Ahr). Hence is recognized also as dioxin-like PCBs [2]. Since PCB 77 can affect the cell also through estrogen [3] and glucocorticoid receptors [4], it is recognized as a significant environmental pollutant and endocrine disruptor [3] with a wide spectrum of way of action. Admittedly 2,2',4,4', 5,5'-hexachlorobiphenyl PCB 153 is also one of the most prominent environmental contaminants, but oppositely to PCB 77 is classified as di-ortho, non-coplanar, non-dioxin congener of PCBs [5] and is known to have rather estrogenic properties [6]. Even though PCBs production and use were banned in USA and Europe more than three decades ago, they are still measured in environment [7]. Due to their lipophilic nature and resistance for biodegradation, PCBs have been bio-accumulated in animal tissues [8], also in domestic animals [9,10]. Therefore PCBs have been also measured in food samples [11] and they can be mentioned as a serious health risk.Since PCBs accumulation in preg...

show abstract

Effects of porcine relaxin on induced parturition in beef heifers

Cited by 6 publications

References 27 publications

Endocrine changes during the peripartal period related to colostrogenesis in mammalian species

Endocrine changes during the peripartal period related to colostrogenesis in mammalian species

Placental contribution to the endocrinology of gestation and parturition

The Preliminary Study About the Involvement of Relaxine in Adverse Effect of Polychlorinated Biphenyls on Bovine Myometrial Contractions

Contact Info

Product

Resources

About