1
|
McCormack SE, Blevins JE, Lawson EA. Metabolic Effects of Oxytocin. Endocr Rev 2020; 41:5658523. [PMID: 31803919 PMCID: PMC7012298 DOI: 10.1210/endrev/bnz012] [Citation(s) in RCA: 60] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/04/2019] [Accepted: 11/04/2019] [Indexed: 12/13/2022]
Abstract
There is growing evidence that oxytocin (OXT), a hypothalamic hormone well recognized for its effects in inducing parturition and lactation, has important metabolic effects in both sexes. The purpose of this review is to summarize the physiologic effects of OXT on metabolism and to explore its therapeutic potential for metabolic disorders. In model systems, OXT promotes weight loss by decreasing energy intake. Pair-feeding studies suggest that OXT-induced weight loss may also be partly due to increased energy expenditure and/or lipolysis. In humans, OXT appears to modulate both homeostatic and reward-driven food intake, although the observed response depends on nutrient milieu (eg, obese vs. nonobese), clinical characteristics (eg, sex), and experimental paradigm. In animal models, OXT is anabolic to muscle and bone, which is consistent with OXT-induced weight loss occurring primarily via fat loss. In some human observational studies, circulating OXT concentrations are also positively associated with lean mass and bone mineral density. The impact of exogenous OXT on human obesity is the focus of ongoing investigation. Future randomized, placebo-controlled clinical trials in humans should include rigorous, standardized, and detailed assessments of adherence, adverse effects, pharmacokinetics/pharmacodynamics, and efficacy in the diverse populations that may benefit from OXT, in particular those in whom hypothalamic OXT signaling may be abnormal or impaired (eg, individuals with Sim1 deficiency, Prader-Willi syndrome, or craniopharyngioma). Future studies will also have the opportunity to investigate the characteristics of new OXT mimetic peptides and the obligation to consider long-term effects, especially when OXT is given to children and adolescents. (Endocrine Reviews XX: XX - XX, 2020).
Collapse
Affiliation(s)
- Shana E McCormack
- Neuroendocrine Center, Division of Endocrinology and Diabetes, Children's Hospital of Philadelphia, Philadelphia, Pennsylvania.,Department of Pediatrics, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, Pennsylvania
| | - James E Blevins
- VA Puget Sound Health Care System, Office of Research and Development Medical Research Service, Department of Veterans Affairs Medical Center, Seattle, Washington.,Division of Metabolism, Endocrinology and Nutrition, Department of Medicine, University of Washington School of Medicine, Seattle, Washington
| | - Elizabeth A Lawson
- Neuroendocrine Unit, Massachusetts General Hospital, Boston, Massachusetts.,Department of Medicine, Harvard Medical School, Boston, Massachusetts
| |
Collapse
|
2
|
A Pilot Study of Oxytocin in Low-Income Women With a Low Birth-Weight Infant: Is Oxytocin Related to Posttraumatic Stress? Adv Neonatal Care 2019; 19:E12-E21. [PMID: 30893095 DOI: 10.1097/anc.0000000000000601] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
BACKGROUND Negative outcomes related to prematurity may lead to maternal distress. Mothers of premature/low birth-weight infants report increased posttraumatic stress (50%) and depressive symptoms (63%) compared with mothers of full-term infants. Low-income, minority mothers with greater posttraumatic stress and depression have an increased risk for premature/low birth-weight delivery compared with their white counterparts. Variations in the neuropeptide oxytocin are implicated in lactation, perinatal depression, and maternal behavior. PURPOSE To examine the associations among posttraumatic stress, depressive symptoms, and oxytocin in a pilot sample of minority mothers with premature/low birth-weight infants in the neonatal intensive care unit (NICU). METHODS This study employed a descriptive, correlational pilot design of 8 minority, low-income mothers with premature/low birth-weight infants. Participants answered questionnaires pertaining to posttraumatic stress, depression, lactation, and demographics and oxytocin was measured. This is a substudy that added oxytocin values. RESULTS Four participants had elevated depressive symptoms and 5 supplied their own milk. Women who provided their own milk had lower depressive (t = 3.03, P = .023) and posttraumatic stress (t = 3.39, P = .015) symptoms compared with women not supplying their own milk. Women with elevated posttraumatic stress had higher levels of depressive symptoms (r(8) = 0.8, P = .006) and lower levels of oxytocin (r(8) = 0.77, P = .026). IMPLICATIONS FOR PRACTICE These results are congruent with previous literature on providing human milk and maternal mental health. In addition, we found a possible relationship between postpartum posttraumatic stress and oxytocin in minority women with premature/low birth-weight infants. NICU nurses should encourage lactation and assess mothers for posttraumatic stress and depressive symptoms. IMPLICATIONS FOR RESEARCH Research is needed to identify the biologic milieu associated with posttraumatic stress and depression in at-risk mothers.
Collapse
|
3
|
Baskaran C, Plessow F, Silva L, Asanza E, Marengi D, Eddy KT, Sluss PM, Johnson ML, Misra M, Lawson EA. Oxytocin secretion is pulsatile in men and is related to social-emotional functioning. Psychoneuroendocrinology 2017; 85:28-34. [PMID: 28800490 PMCID: PMC5636187 DOI: 10.1016/j.psyneuen.2017.07.486] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/30/2017] [Revised: 07/18/2017] [Accepted: 07/19/2017] [Indexed: 01/19/2023]
Abstract
UNLABELLED The hypothalamic hormone oxytocin (OXT) plays an important role in a range of physiological processes and social-emotional functioning in both sexes. In women, physiological stimuli, such as suckling and parturition, result in pulsatile release of OXT into the peripheral circulation via the posterior pituitary gland. However, data regarding OXT secretory patterns in men during a state of rest are limited. Further, the relationship between secretory dynamics of OXT and emotional measures has never been evaluated. We hypothesized a pulsatile pattern of OXT secretion in men, and explored the relationship between OXT secretory patterns and social-emotional functioning. METHODS Deconvolution analysis was performed on serum OXT levels obtained every 5min over a period of 10h in 5 healthy normal weight men. Area under the curve (AUC), average OXT values, and pulse characteristics [pulse number, inter-pulse interval, pulse height and mass (area under each pulse)] were calculated. State Adult Attachment Measure (SAAM) assessed types of human attachment. Interpersonal Support Evaluation List (ISEL) assessed perception of social support. Toronto Alexithymia Scale (TAS-20) measured the ability to express and identify one's own emotions. RESULTS Mean age was 22.8±1.2years, and BMI was 21.7±0.4kg/m2 (mean±SEM). Assuming a basal secretion of zero and a half life of five to seven minutes, we demonstrated the following: OXT AUC: 5421±1331pg/ml, mean OXT level: 9.1pg/ml, mean pulse number: 22±3/10hr, mean pulse height: 1.81±0.48pg/ml, mean pulse mass: 30.34±10.29pg/ml and mean inter-pulse interval: 27±4min. The SAAM Avoidant scale correlated negatively with mean OXT pulse height (r=-0.90, p=0.04) and pulse mass (r=-0.95, p=0.01). The ISEL Belonging score correlated positively with OXT AUC (r=0.89, p=0.04) and average OXT (r=0.93, p=0.02). ISEL Appraisal score also had a positive association with mean OXT pulse height (r=0.99, p=0.0006) and pulse mass (r=0.98, p=0.003). Finally, ISEL total score had a significant correlation with average OXT values (r=0.90, p=0.04). While none of the subjects had a score in the alexithymia range, TAS-20 Difficulty describing feelings score had an inverse correlation with OXT pulse height (r=-0.96, p=0.01) and pulse mass (r=-0.99, p=0.001). TAS-20 total score also had an inverse correlation with OXT pulse height (r=-0.94, p=0.02) and pulse mass (r=-0.96, p=0.009). CONCLUSION We demonstrate a pulsatile pattern of peripheral OXT secretion in healthy men at rest. Subjects with lower OXT pulse height and pulse mass had a more avoidant style of attachment, felt less supported, and expressed greater difficulty in describing their feelings. Our findings support the concept that OXT is a key mediator of social-emotional functioning. Future studies to determine causality are warranted.
Collapse
Affiliation(s)
- Charu Baskaran
- Pediatric Endocrine Unit, Massachusetts General Hospital for Children and Harvard Medical School, Boston, MA, USA,Neuroendocrine Unit, Massachusetts General Hospital and Harvard Medical School, Boston, MA, USA
| | - Franziska Plessow
- Neuroendocrine Unit, Massachusetts General Hospital and Harvard Medical School, Boston, MA, USA
| | - Lisseth Silva
- Neuroendocrine Unit, Massachusetts General Hospital and Harvard Medical School, Boston, MA, USA
| | - Elisa Asanza
- Neuroendocrine Unit, Massachusetts General Hospital and Harvard Medical School, Boston, MA, USA
| | - Dean Marengi
- Neuroendocrine Unit, Massachusetts General Hospital and Harvard Medical School, Boston, MA, USA
| | - Kamryn T. Eddy
- Eating Disorder Clinical Research Program, Massachusetts General Hospital for Children and Harvard Medical School, Boston, MA, USA
| | - Patrick M Sluss
- Neuroendocrine Unit, Massachusetts General Hospital and Harvard Medical School, Boston, MA, USA
| | - Michael L Johnson
- Departments of Pharmacology and Internal Medicine, University of Virginia, Charlottesville, VA, USA
| | - Madhusmita Misra
- Pediatric Endocrine Unit, Massachusetts General Hospital for Children and Harvard Medical School, Boston, MA, USA,Neuroendocrine Unit, Massachusetts General Hospital and Harvard Medical School, Boston, MA, USA
| | - Elizabeth A Lawson
- Neuroendocrine Unit, Massachusetts General Hospital and Harvard Medical School, Boston, MA, USA
| |
Collapse
|
4
|
Finkenwirth C, van Schaik C, Ziegler TE, Burkart JM. Strongly bonded family members in common marmosets show synchronized fluctuations in oxytocin. Physiol Behav 2015; 151:246-51. [PMID: 26232089 PMCID: PMC5916785 DOI: 10.1016/j.physbeh.2015.07.034] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2015] [Revised: 07/23/2015] [Accepted: 07/27/2015] [Indexed: 11/16/2022]
Abstract
Oxytocin is a key regulator of social bonding and is positively linked to affiliation and prosocial behavior in several mammal species. In chimpanzees, this link is dyad-specific as affiliative interactions only elicit high oxytocin release if they involve strongly bonded individuals. These studies involved isolated dyads and sampling events. Little is known about the role of oxytocin in affiliation and social bonding, and about potential long-term patterns of bonding-related and dyad-specific oxytocin effects within highly affiliative and cooperative social groups. Our aim was to investigate whether bonding-related oxytocin signatures linked to dyadic affiliation are present in family groups of cooperatively breeding marmoset monkeys (Callithrix jacchus) that show high levels of cohesion and cooperation. In 30 dyads from four family groups and one pair, we measured urinary baseline oxytocin over six weeks and analyzed the link to bond strength (mean dyadic affiliation). Strongly bonded dyads showed synchronized longitudinal fluctuations of oxytocin, indicating that dyad-specific oxytocin effects can also be traced in the group context and in an interdependent species. We discuss these results in light of the potential function of differentiated relationships between marmoset dyads other than the breeding pair, and the role of oxytocin as a mediator for social bonding.
Collapse
Affiliation(s)
- Christa Finkenwirth
- Anthropological Institute and Museum, University of Zurich, Winterthurerstrasse 190, 8057 Zurich, Switzerland.
| | - Carel van Schaik
- Anthropological Institute and Museum, University of Zurich, Winterthurerstrasse 190, 8057 Zurich, Switzerland
| | - Toni E Ziegler
- Wisconsin National Primate Research Center, University of Wisconsin, Madison, WI 53715, USA
| | - Judith M Burkart
- Anthropological Institute and Museum, University of Zurich, Winterthurerstrasse 190, 8057 Zurich, Switzerland
| |
Collapse
|
5
|
Primate enamel evinces long period biological timing and regulation of life history. J Theor Biol 2012; 305:131-44. [DOI: 10.1016/j.jtbi.2012.04.007] [Citation(s) in RCA: 71] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2012] [Revised: 03/28/2012] [Accepted: 04/05/2012] [Indexed: 11/21/2022]
|
6
|
|
7
|
Abstract
In many nonprimate mammalian species, cyclical regression of the corpus luteum (luteolysis) is caused by the episodic pulsatile secretion of uterine PGF2alpha, which acts either locally on the corpus luteum by a countercurrent mechanism or, in some species, via the systemic circulation. Hysterectomy in these nonprimate species causes maintenance of the corpora lutea, whereas in primates, removal of the uterus does not influence the cyclical regression of the corpus luteum. In several nonprimate species, the episodic pattern of uterine PGF2alpha secretion appears to be controlled indirectly by the ovarian steroid hormones estradiol-17beta and progesterone. It is proposed that, toward the end of the luteal phase, loss of progesterone action occurs both centrally in the hypothalamus and in the uterus due to the catalytic reduction (downregulation) of progesterone receptors by progesterone. Loss of progesterone action may permit the return of estrogen action, both centrally in the hypothalamus and peripherally in the uterus. Return of central estrogen action appears to cause the hypothalamic oxytocin pulse generator to alter its frequency and produce a series of intermittent episodes of oxytocin secretion. In the uterus, returning estrogen action concomitantly upregulates endometrial oxytocin receptors. The interaction of neurohypophysial oxytocin with oxytocin receptors in the endometrium evokes the secretion of luteolytic pulses of uterine PGF2alpha. Thus the uterus can be regarded as a transducer that converts intermittent neural signals from the hypothalamus, in the form of episodic oxytocin secretion, into luteolytic pulses of uterine PGF2alpha. In ruminants, portions of a finite store of luteal oxytocin are released synchronously by uterine PGF2alpha pulses. Luteal oxytocin in ruminants may thus serve to amplify neural oxytocin signals that are transduced by the uterus into pulses of PGF2alpha. Whether such amplification of episodic PGF2alpha pulses by luteal oxytocin is a necessary requirement for luteolysis in ruminants remains to be determined. Recently, oxytocin has been reported to be produced by the endometrium and myometrium of the sow, mare, and rat. It is possible that uterine production of oxytocin may act as a supplemental source of oxytocin during luteolysis in these species. In primates, oxytocin and its receptor and PGF2alpha and its receptor have been identified in the corpus luteum and/or ovary. Therefore, it is possible that oxytocin signals of ovarian and/or neural origin may be transduced locally at the ovarian level, thus explaining why luteolysis and ovarian cyclicity can proceed in the absence of the uterus in primates. However, it remains to be established whether the intraovarian process of luteolysis is mediated by arachidonic acid and/or its metabolite PGF2alpha and whether the central oxytocin pulse generator identified in nonprimate species plays a mediatory role during luteolysis in primates. Regardless of the mechanism, intraovarian luteolysis in primates (progesterone withdrawal) appears to be the primary stimulus for the subsequent production of endometrial prostaglandins associated with menstruation. In contrast, luteolysis in nonprimate species appears to depend on the prior production of endometrial prostaglandins. In primates, uterine prostaglandin production may reflect a vestigial mechanism that has been retained during evolution from an earlier dependence on uterine prostaglandin production for luteolysis.
Collapse
Affiliation(s)
- J A McCracken
- Worcester Foundation for Biomedical Research, Shrewsbury, Massachusetts, USA
| | | | | |
Collapse
|
8
|
MIYAMOTO A, TAKASE SI, TASHIRO Y, KONARI A, TOMINO M, ABE N, TAGUCHI K, FUKUI Y. Local Release of Progesterone and Oxytocin from Microdialyzed Corpus Luteum in Superovulated Ewes: Characterization during the Non-breeding Season. J Reprod Dev 1995. [DOI: 10.1262/jrd.41.321] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Affiliation(s)
- Akio MIYAMOTO
- Laboratory of Animal Genetics and Reproduction, Obihiro University of Agriculture and Veterinary Medicine, Obihiro 080, Japan
| | - Shun-ichi TAKASE
- Laboratory of Animal Genetics and Reproduction, Obihiro University of Agriculture and Veterinary Medicine, Obihiro 080, Japan
| | - Yumiko TASHIRO
- Laboratory of Animal Genetics and Reproduction, Obihiro University of Agriculture and Veterinary Medicine, Obihiro 080, Japan
| | - Atsuhiko KONARI
- Laboratory of Animal Genetics and Reproduction, Obihiro University of Agriculture and Veterinary Medicine, Obihiro 080, Japan
| | - Mikiko TOMINO
- Laboratory of Animal Genetics and Reproduction, Obihiro University of Agriculture and Veterinary Medicine, Obihiro 080, Japan
| | - Noritsugu ABE
- Laboratory of Veterinary Sugery, Obihiro University of Agriculture and Veterinary Medicine, Obihiro 080, Japan
| | - Kiyoshi TAGUCHI
- Laboratory of Veterinary Sugery, Obihiro University of Agriculture and Veterinary Medicine, Obihiro 080, Japan
| | - Yutaka FUKUI
- Laboratory of Animal Genetics and Reproduction, Obihiro University of Agriculture and Veterinary Medicine, Obihiro 080, Japan
| |
Collapse
|
9
|
Abstract
Serum profiles of oxytocin were studied by means of a continuous blood sampling system in five young healthy women before and during treatment with a combined oral contraceptive. Oxytocin levels were determined by a specific radioimmunoassay in blood samples collected in 10-min fractions from 22.00 to 06.00. The values were further analyzed by the pulse detection program PULSAR. Great individual differences in oxytocin profiles were observed, and in some of the women these differences were also pronounced between the two sampling occasions. All 10 profiles demonstrated irregular peaks which occurred with varying frequency. Although the baseline level of oxytocin increased in all women and the average concentration increased in four of the women during treatment, there was no clear-cut effect on the peak frequency. Based on results from animal experiments, it is suggested that the increase in oxytocin levels may be related to an excitatory effect exerted by estrogen on oxytocin secreting neurons.
Collapse
Affiliation(s)
- S Stock
- Department of Woman and Child Health, Karolinska Hospital, Stockholm, Sweden
| | | | | |
Collapse
|
10
|
Wathes DC, Gilbert CL, Ayad VJ. Interactions between oxytocin, the ovaries, and the reproductive tract in the regulation of fertility in the ewe. Ann N Y Acad Sci 1993; 689:396-410. [PMID: 8396872 DOI: 10.1111/j.1749-6632.1993.tb55563.x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Affiliation(s)
- D C Wathes
- AFRC Institute of Animal Physiology and Genetics Research, Babraham, Cambridge, United Kingdom
| | | | | |
Collapse
|
11
|
Fuchs AR, Romero R, Keefe D, Parra M, Oyarzun E, Behnke E. Oxytocin secretion and human parturition: pulse frequency and duration increase during spontaneous labor in women. Am J Obstet Gynecol 1991; 165:1515-23. [PMID: 1957888 DOI: 10.1016/0002-9378(91)90399-c] [Citation(s) in RCA: 64] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
The secretory pattern of oxytocin was determined in blood samples taken at 1-minute intervals for 30 minutes from 32 parturient women. The samples were collected in a manner that minimized degradation by plasma oxytocinase, and a highly specific antibody was used for the radioimmunoassay. The results indicated that oxytocin is secreted in discrete pulses of short duration. The frequency of the pulses was significantly higher during spontaneous labor than before the onset of labor. The mean pulse frequencies per 30 minutes were 1.2 +/- 0.54 before labor, 4.2 +/- 0.45 during the first stage, and 6.7 +/- 0.49 during the second and third stages of labor. The mean pulse durations in these three groups were 1.2 +/- 0.20, 1.9 +/- 0.28, and 2.0 +/- 0.26 minutes, respectively. The amplitude of the pulses was variable with no significant differences between the groups, the majority being around 1.0 microU/ml. The spontaneous pulses were of similar magnitude as those measured in 18 women after intravenous injections of 4 to 16 mU of oxytocin, which doses stimulated uterine contractions. We therefore conclude that the pulses of oxytocin observed at increasing frequency during spontaneous labor are of physiologic significance and provide evidence for the participation of oxytocin in the onset and maintenance of spontaneous labor.
Collapse
Affiliation(s)
- A R Fuchs
- Department of Obstetrics and Gynecology, Cornell University Medical College, New York, NY 10021
| | | | | | | | | | | |
Collapse
|
12
|
Fuchs AR, Romero R, Keefe D, Parra M, Oyarzun E, Behnke E. Oxytocin secretion and human parturition: Pulse frequency and duration increase during spontaneous labor in women. Am J Obstet Gynecol 1991. [DOI: 10.1016/s0002-9378(12)90793-0] [Citation(s) in RCA: 85] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
|
13
|
Ottlecz A, Walker S, Conrad M, Starcher B. Neutral metalloendopeptidase associated with the smooth muscle cells of pregnant rat uterus. J Cell Biochem 1991; 45:401-11. [PMID: 2045432 DOI: 10.1002/jcb.240450414] [Citation(s) in RCA: 25] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
The pregnant rat uterus contains a membrane-bound metalloendopeptidase that is biochemically and immunologically similar to kidney enkephalinase (E.C.3.4.24.11). The uterus enzyme readily cleaved specific neutral endopeptidase substrates and oxytocin as well as the synthetic elastase substrate, Suc(Ala)3-pNA, yet did not digest native elastin. Using specific inhibitors, the uterus endopeptidase was identified as a metallopeptidase and not a serine protease, having an absolute requirement for zinc and perhaps calcium for maximal activity. The uterus endopeptidase cross-reacted with polyclonal antiserum to kidney microvillar endopeptidase and a monoclonal antibody to common acute lymphocytic leukemia antigen. Immunohistochemical localization of the enzyme in a 17 day pregnant uterus indicated that the enzyme was localized on the smooth muscle bundles of the myometrium and the endometrial epithelium. Total enzyme activity was 25 times higher in the late-term pregnant uterus (17th day of pregnancy) than in the nonpregnant uterus. Enzyme levels dropped rapidly prior to parturition and within 4 days after delivery the enzyme activity had returned to control levels. Inhibition of NEP in uterine strips with phosphoramidon resulted in a marked potentiation of oxytocin-induced contractions. Our results suggest that the uterine endopeptidase may have an important role in regulating uterine smooth muscle cell contraction during the later stages of pregnancy through its action on oxytocin and perhaps other biologically active peptides.
Collapse
Affiliation(s)
- A Ottlecz
- Department of Biochemistry, University of Texas Health Center, Tyler 75710
| | | | | | | |
Collapse
|
14
|
al-Eknah MM, Homeida AM. A review of some aspects of the pharmacology of oxytocin in domestic animals. Vet Res Commun 1991; 15:45-55. [PMID: 2048287 DOI: 10.1007/bf00497789] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Affiliation(s)
- M M al-Eknah
- College of Veterinary Medicine and Animal Resources, King Faisal University, Al-Ahsa, Saudi Arabia
| | | |
Collapse
|
15
|
Pimentel G, Poore ER, Nathanielsz PW. The effect of continuous or pulsatile administration of oxytocin to ewes at 126 to 136 days' gestation on myometrial activity and fetal oxygenation. Am J Obstet Gynecol 1989; 160:242-7. [PMID: 2492148 DOI: 10.1016/0002-9378(89)90129-4] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Oxytocin was infused either continuously or in pulses to pregnant ewes to compare the responses of myometrial activity (contractures) and changes in fetal arterial PO2. Group 1 (n = 5) was infused with saline solution throughout the experiment. In group 2 (n = 5) oxytocin was infused continuously (160 microU.kg-1.min-1) for 7 days whereas group 3 (n = 5) ewes received 960 microU.kg-1.min-1 for 5 minutes every 30 minutes for 7 days. Contracture frequency increased in both oxytocin-infused groups. With continuous infusion contracture frequency returned to preinfusion levels during the last 4 days of infusion, whereas the pulsatile infusion contracture frequency remained increased throughout the infusion period. Fetal arterial PO2 was decreased throughout the 7 days of infusion in both oxytocin-infused groups. Pulsatile group fetal arterial PO2 levels remained decreased after the oxytocin infusion was stopped. These findings show: (1) Myometrial response to oxytocin in late pregnant ewes is influenced by the mode of administration; (2) administration of oxytocin to pregnant ewes resulted in a decrease in fetal PO2, and thus fetal hypoxemia cannot be attributed exclusively to increased contracture frequency.
Collapse
Affiliation(s)
- G Pimentel
- Department of Physiology, New York State College of Veterinary Medicine, Cornell University, Ithaca 14853
| | | | | |
Collapse
|
16
|
Kendrick KM, Keverne EB, Chapman C, Baldwin BA. Intracranial dialysis measurement of oxytocin, monoamine and uric acid release from the olfactory bulb and substantia nigra of sheep during parturition, suckling, separation from lambs and eating. Brain Res 1988; 439:1-10. [PMID: 3359176 DOI: 10.1016/0006-8993(88)91455-2] [Citation(s) in RCA: 130] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
Intracranial dialysis was used to measure the release of oxytocin (OXY), monoamines and their metabolites and uric acid (UA) from the substantia nigra (SN) and olfactory bulb (OB) of sheep during parturition, suckling, separation from lambs and eating. Results showed that OXY concentrations increased significantly during parturition, suckling and eating in the SN and during parturition and suckling in the OB. Concentrations of dopamine (DA) increased significantly in the SN during suckling and eating and in the OB during parturition and suckling. The dopamine metabolite, homovanillic acid, also increased significantly in the SN during parturition. Concentrations of the noradrenaline metabolite, 4-hydroxy-3-methoxyphenylethan-1,2-diol (MHPG) and the purine metabolite, UA, were significantly raised during parturition, suckling and separation from the lambs in the SN and increased UA levels were also found during eating. In a separate experiment it was confirmed that OXY was detectable in homogenates of both the SN and the OB. These results show that, in the sheep, OXY and DA release in the SN is associated with maternal and ingestive behaviour whereas similar release in the OB may only be related to maternal behaviour. Release of MHPG in the SN may be associated with maternal behaviour and/or stress.
Collapse
Affiliation(s)
- K M Kendrick
- AFRC Institute of Animal Physiology and Genetics Research, Cambridge, U.K
| | | | | | | |
Collapse
|
17
|
Krehbiel D, Poindron P, Lévy F, Prud'Homme MJ. Peridural anesthesia disturbs maternal behavior in primiparous and multiparous parturient ewes. Physiol Behav 1987; 40:463-72. [PMID: 3628543 DOI: 10.1016/0031-9384(87)90031-x] [Citation(s) in RCA: 55] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
Several experiments were carried out to study the effects of peridural anesthesia (Sylvocaine, 6 ml between sacrum and 1st caudal vertebra) performed either at the first signs of birth (early peridural: EP), or little before expulsion (late peridural: LP). When performed late, peridural anesthesia altered maternal behavior only slightly when compared with controls. By contrast severe deficits were observed in the case of EP. Seven out of 8 primiparae failed to show interest for their lamb within 30 min of the birth of the young (vs. 1/9 in LP group, p less than 0.01). In multiparae these proportions were 8/27 and 0/22 respectively (p less than 0.01). Within the EP group the effects of the peridural were more marked in primiparous than in multiparous mothers (p less than 0.05). Even in EP multiparous ewes becoming maternal within 5 min after giving birth a reduction in duration of licking was noted, when compared with the LP group (p less than 0.05). On the other hand, these same ewes established normally a selective bond within 2 hours after giving birth, as did the LP or control ewes. These results confirm the importance of genital stimulation for the rapid onset of maternal behavior in parturient ewes. They failed however to clarify the role played by genital stimulation in the establishment of a selective maternal bond.
Collapse
|
18
|
Komisaruk BR, Steinman JL. Genital stimulation as a trigger for neuroendocrine and behavioral control of reproduction. Ann N Y Acad Sci 1986; 474:64-75. [PMID: 3555246 DOI: 10.1111/j.1749-6632.1986.tb27999.x] [Citation(s) in RCA: 25] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
|
19
|
|
20
|
|
21
|
Garcia-Villar R, Toutain P, Ruckebusch Y. Differential responsiveness to oxytocin of the uterus and cervix in the ovariectomized ewe. Anim Reprod Sci 1984. [DOI: 10.1016/0378-4320(84)90044-7] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
|
22
|
McCracken J, Schramm W, Okulicz W. Hormone receptor control of pulsatile secretion of PGF2α from the ovine uterus during luteolysis and its abrogation in early pregnancy. Anim Reprod Sci 1984. [DOI: 10.1016/0378-4320(84)90027-7] [Citation(s) in RCA: 123] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
|
23
|
Cooke R, Homeida A. Delayed luteolysis and suppression of the pulsatile release of oxytocin after indomethacin treatment in the goat. Res Vet Sci 1984. [DOI: 10.1016/s0034-5288(18)32000-9] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
|
24
|
Schramm W, Bovaird L, Glew ME, Schramm G, McCracken JA. Corpus luteum regression induced by ultra-low pulses of prostaglandin F2 alpha. PROSTAGLANDINS 1983; 26:347-64. [PMID: 6581508 DOI: 10.1016/0090-6980(83)90171-5] [Citation(s) in RCA: 65] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
In view of the pulsatile nature of PGF2 alpha secretion from the ovine uterus at the time of luteolysis, experiments were designed to examine the effect of pulsed infusions of PGF2 alpha on luteal function and to re-examine the minimal effective levels of PGF2 alpha required to induce luteolysis. To mimic physiological conditions, hour-long infusions of PGF2 alpha in increasing concentrations were given either 4 times in 19 h or 5 times in 25 h into the arterial supply of the autotransplanted ovary in conscious sheep on day 12 of an induced cycle. Blood flow and progesterone secretion rate from the ovary were used to monitor directly the luteolytic effect of administered PGF2 alpha. The concentration of LH in peripheral plasma was measured throughout each infusion experiment and the presence of a preovulatory peak of LH was used as an indicator of the permanence of luteal regression. Four pulses of PGF2 alpha in 19 h caused complete corpus luteum regression in only 1 of 4 animals whereas the addition of a fifth pulse (5 pulses in 25 h) caused permanent regression in 4 out of 4 animals. Infusion of 5 hour-long pulses of saline or PGF2 alpha at a rate less than 0.04 microgram/h did not induce permanent suppression of progesterone secretion. The average total effective dose of PGF2 alpha required to induce luteal regression when given as 5 pulses was 1/40th of the amount currently regarded as the minimal effective one when given by constant infusion into the ovarian artery. In another series of experiments the luteolytic effect of a single hour-long pulse of 0.1 microgram/h PGF2 alpha given daily for either 3 or 4 days was investigated. A significant fall (ANOVA, F0.01) in progesterone secretion rate, which reached a nadir at 5.3 +/- 2.2 h (means +/- S.D., n = 15), was followed by a recovery of progesterone secretion rate. Permanent luteal regression did not occur with this protracted regimen, suggesting that a relatively short pulse frequency of PGF2 alpha over a minimal period of 24 h is a necessary condition for physiological regression of the corpus luteum in sheep.
Collapse
|