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Tsukamoto H, Olesen ND, Petersen LG, Suga T, Sørensen H, Nielsen HB, Ogoh S, Secher NH, Hashimoto T. Circulating Plasma Oxytocin Level Is Elevated by High-Intensity Interval Exercise in Men. Med Sci Sports Exerc 2024; 56:927-932. [PMID: 38115226 DOI: 10.1249/mss.0000000000003360] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2023]
Abstract
PURPOSE We evaluated whether repeated high-intensity interval exercise (HIIE) influences plasma oxytocin (OT) concentration in healthy men, and, given that OT is mainly synthesized in the hypothalamus, we assessed the concentration difference between the arterial (OT ART ) versus the internal jugular venous OT concentration (OT IJV ). Additionally, we hypothesized that an increase in cerebral OT release and the circulating concentration would be augmented by repeated HIIE. METHODS Fourteen healthy men (age = 24 ± 2 yr; mean ± SD) performed two identical bouts of HIIE. These HIIE bouts included a warm-up at 50%-60% maximal workload ( Wmax ) for 5 min followed by four bouts of exercise at 80%-90% Wmax for 4 min interspersed by exercise at 50%-60% Wmax for 3 min. The HIIE bouts were separated by 60 min of rest. OT was evaluated in blood through radial artery and internal jugular vein catheterization. RESULTS Both HIIE bouts increased both OT ART (median [IQR], from 3.9 [3.4-5.4] to 5.3 [4.4-6.3] ng·mL -1 in the first HIIE, P < 0.01) and OT IJV (from 4.6 [3.4-4.8] to 5.9 [4.3-8.2] ng·mL -1 , P < 0.01), but OT ART-IJV was unaffected (from -0.24 [-1.16 to 1.08] to 0.04 [-0.88 to 0.78] ng·mL -1 , P = 1.00). The increased OT levels were similar in the first and second HIIE bouts (OT ARTP = 0.25, OT IJVP = 0.36). CONCLUSIONS Despite no change in the cerebral OT release via the internal jugular vein, circulating OT increases during HIIE regardless of the accumulated exercise volume, indicating that OT may play role as one of the exerkines.
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Affiliation(s)
| | | | | | - Tadashi Suga
- Institute of Advanced Research for Sport and Health Science, Ritsumeikan University, Shiga, JAPAN
| | - Henrik Sørensen
- Department of Anesthesia, Rigshospitalet, Department of Clinical Medicine, University of Copenhagen, Copenhagen, DENMARK
| | | | - Shigehiko Ogoh
- Department of Biomedical Engineering, Toyo University, Saitama, JAPAN
| | - Niels H Secher
- Department of Anesthesia, Rigshospitalet, Department of Clinical Medicine, University of Copenhagen, Copenhagen, DENMARK
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Santos LFG, Fernandes-Breitenbach F, Silva RAS, Santos DR, Peres-Ueno MJ, Ervolino E, Chaves-Neto AH, Dornelles RCM. The action of oxytocin on the bone of senescent female rats. Life Sci 2022; 297:120484. [PMID: 35301015 DOI: 10.1016/j.lfs.2022.120484] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2022] [Revised: 03/07/2022] [Accepted: 03/10/2022] [Indexed: 10/18/2022]
Abstract
AIMS This study verified the action of oxytocin (OT) as a preventive measure to control bone damage during aging in female rats. MAIN METHODS Wistar rats received saline (0.15 mol/L/IP; Vehicle Group), Atosiban/AT (300 μg/Kg/IP; At Group), OT (134 μg/Kg/IP; Ot Group), or AT+OT (OT injections 5 min after AT; At+Ot Group), at 19 and 20 months of age. A functional test was performed immediately before and 30 days after the injections to analyze the animals' gait. KEY FINDINGS Animals in the At group had higher alkaline phosphatase (ALP) activity, lower cortical and trabecular thickness, fewer trabeculae, higher expression of tartrate-resistant acid phosphatase (TRAP) and lower osteocalcin (OCN), higher cortical porosity, and lower moment of inertia and bone strength at the femoral neck. OT administration increased lipidic peroxidation and plasma superoxide dismutase (SOD), and provided, in the femoral neck, lower expression of TRAP and higher OCN, greater cortical and trabecular thickness, a greater number of trabeculae, bone mineral density (BMD), higher inertia bone strength, and lower cortical porosity. At + Ot group showed great similarity with the vehicle group, higher SOD, and BMD. An increase in stride length and no increase in base width of 21-month-old animals were observed after OT, unlike animal's vehicle or AT. SIGNIFICANCE Endogenous OT plays an important role in the regulation of bone remodeling during periestropause, and exogenous OT stands out as a potential preventive intervention in this period to improve bone quality with functional repercussions, possibly providing better gait activity.
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Affiliation(s)
| | | | | | - Damáris Raíssa Santos
- Programa de Pós-Graduação Multicêntrico em Ciências Fisiológicas/SBFis/UNESP, Brazil
| | | | - Edilson Ervolino
- Department of Basic Sciences, School of Dentistry, São Paulo State University (UNESP), Araçatuba, São Paulo, Brazil
| | - Antonio Hernandes Chaves-Neto
- Programa de Pós-Graduação Multicêntrico em Ciências Fisiológicas/SBFis/UNESP, Brazil; Department of Basic Sciences, School of Dentistry, São Paulo State University (UNESP), Araçatuba, São Paulo, Brazil
| | - Rita Cássia Menegati Dornelles
- Programa de Pós-Graduação Multicêntrico em Ciências Fisiológicas/SBFis/UNESP, Brazil; Department of Basic Sciences, School of Dentistry, São Paulo State University (UNESP), Araçatuba, São Paulo, Brazil.
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Marazziti D, Avella MT, Ivaldi T, Palermo S, Massa L, Vecchia AD, Basile L, Mucci F. Neuroenhancement: State of the Art and Future Perspectives. CLINICAL NEUROPSYCHIATRY 2021; 18:137-169. [PMID: 34909030 PMCID: PMC8629054 DOI: 10.36131/cnfioritieditore20210303] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Pharmacological neuroenhancement refers to the non-medical use of prescription drugs, alcohol, illegal drugs, or the so-called soft enhancers for the purpose of improving cognition, mood, pro-social behavior, or work and academic performance. This phenomenon is undoubtedly more frequent than previously supposed especially amongst university students. The aim of the present paper was to carefully review and comment on the available literature on neuroenhancement, according to Prisma guidelines. The results showed a great use of all prescribed drugs (benzodiazepines, antidepressants, antipsychotics, nootropic compounds, and especially stimulants) as neuroenhancers amongst healthy subjects, although probably the real prevalence is underestimated. The use of illicit drugs and soft enhancers is similarly quite common. Data on the improvement of cognition by other compounds, such as oxytocin and pheromones, or non-pharmacological techniques, specifically deep brain stimulation and transcranial magnetic stimulation, are still limited. In any case, if it is true that human beings are embedded by the desire to overcome the limits of their intrinsic nature, neuroenhancement practices put into question the concept of authenticity. Therefore, the problem appears quite complex and requires to be deepened and analyzed with no prejudice, although within an ethical conceptual frame.
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Affiliation(s)
- Donatella Marazziti
- Department of Clinical and Experimental Medicine, Section of Psychiatry, University of Pisa, Italy
- Unicamillus-Saint Camillus International University of Health Sciences, Rome, Italy
| | - Maria Teresa Avella
- Department of Clinical and Experimental Medicine, Section of Psychiatry, University of Pisa, Italy
| | - Tea Ivaldi
- Department of Clinical and Experimental Medicine, Section of Psychiatry, University of Pisa, Italy
| | - Stefania Palermo
- Department of Clinical and Experimental Medicine, Section of Psychiatry, University of Pisa, Italy
| | - Lucia Massa
- Department of Clinical and Experimental Medicine, Section of Psychiatry, University of Pisa, Italy
| | - Alessandra Della Vecchia
- Department of Clinical and Experimental Medicine, Section of Psychiatry, University of Pisa, Italy
| | - Lucia Basile
- Department of Clinical and Experimental Medicine, Section of Psychiatry, University of Pisa, Italy
| | - Federico Mucci
- Department of Biotechnology, Chemistry and Pharmacy, University of Siena, Italy
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Adverse effects of 4-tert-octylphenol on the production of oxytocin and hCG in pregnant rats. Lab Anim Res 2014; 30:123-30. [PMID: 25324873 PMCID: PMC4188831 DOI: 10.5625/lar.2014.30.3.123] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2014] [Revised: 09/03/2014] [Accepted: 09/04/2014] [Indexed: 01/31/2023] Open
Abstract
Endocrine-disrupting chemicals (EDCs) are exogenous substances that alter the structure or function of the endocrine system. 4-Tert-octylphenol (OP) is one of the most representative EDCs and has estrogenic effects. In this study, we examined the effects of ethinyl estradiol (EE) and OP on the pituitary gland, placenta, and uterus of pregnant rats. Expression levels of human chorionic gonadotropin (hCG), oxytocin (OT), and contraction-associated proteins (CAPs) were determined, and uterine contractile activity was measured by uterine contraction assay. EE and OP both increased mRNA expression of OT and hCG in the pituitary gland but not the placenta. Since OT and hCG control uterine contraction, we next examined CAP expression in the uterus. Expression of 15-hydroxyprostaglandin-dehydrogenase (PGDH) was upregulated by OP, whereas expression of other CAPs was unaffected. To clarify the effect of OP on uterine contraction in pregnant rats, uterine contraction assay was performed. The 17β-Estradiol (E2) did not affect contraction of primary uterine cells harvested from pregnant rats in a 3D collagen gel model. However, OP showed different effects from E2 by significantly reducing contraction activity. In summary, we demonstrated that OP interferes with regulation of OT and hCG in the pituitary gland as well as PGDH in the uterus, thereby reducing uterine contraction activity. This result differs from the action of endogenous E2. Collectively, these findings suggest that exposure to EDCs such as OP during pregnancycan reduce uterine contractile ability, which may result in contraction-associated adverse effects such as metratonia, bradytocia, and uterine leiomyomata.
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Prevost M, Zelkowitz P, Tulandi T, Hayton B, Feeley N, Carter CS, Joseph L, Pournajafi-Nazarloo H, Yong Ping E, Abenhaim H, Gold I. Oxytocin in pregnancy and the postpartum: relations to labor and its management. Front Public Health 2014; 2:1. [PMID: 24479112 PMCID: PMC3902863 DOI: 10.3389/fpubh.2014.00001] [Citation(s) in RCA: 68] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2013] [Accepted: 01/10/2014] [Indexed: 12/04/2022] Open
Abstract
The purpose of this study was to examine variations in endogenous oxytocin levels in pregnancy and postpartum state. We also explored the associations between delivery variables and oxytocin levels. A final sample of 272 mothers in their first trimester of pregnancy was included for the study. Blood samples were drawn during the first trimester and third trimester of pregnancy and at 8 weeks postpartum. Socio-demographic data were collected at each time point and medical files were consulted for delivery details. In most women, levels of circulating oxytocin increased from the first to third trimester of pregnancy followed by a decrease in the postpartum period. Oxytocin levels varied considerably between individuals, ranging from 50 pg/mL to over 2000 pg/mL. Parity was the main predictor of oxytocin levels in the third trimester of pregnancy and of oxytocin level changes from the first to the third trimester of pregnancy. Oxytocin levels in the third trimester of pregnancy predicted a self-reported negative labor experience and increased the chances of having an epidural. Intrapartum exogenous oxytocin was positively associated with levels of oxytocin during the postpartum period. Our exploratory results suggest that circulating oxytocin levels during the third trimester of pregnancy may predict the type of labor a woman will experience. More importantly, the quantity of intrapartum exogenous oxytocin administered during labor predicted plasma oxytocin levels 2 months postpartum, suggesting a possible long-term effect of this routine intervention, the consequences of which are largely unknown.
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Affiliation(s)
- Marie Prevost
- Departments of Psychiatry and Philosophy, McGill University , Montreal, QC , Canada
| | - Phyllis Zelkowitz
- Lady Davis Institute, Jewish General Hospital, McGill University , Montreal, QC , Canada
| | - Togas Tulandi
- Department of Obstetrics and Gynecology, Jewish General Hospital, McGill University , Montreal, QC , Canada
| | - Barbara Hayton
- Lady Davis Institute, Jewish General Hospital, McGill University , Montreal, QC , Canada
| | - Nancy Feeley
- Lady Davis Institute, Jewish General Hospital, McGill University , Montreal, QC , Canada
| | - C Sue Carter
- Department of Psychiatry, University of North Carolina , Chapel Hill, NC , USA
| | - Lawrence Joseph
- Division of Clinical Epidemiology, McGill University , Montreal, QC , Canada
| | | | - Erin Yong Ping
- Departments of Psychiatry and Philosophy, McGill University , Montreal, QC , Canada
| | - Haim Abenhaim
- Department of Obstetrics and Gynecology, Jewish General Hospital, McGill University , Montreal, QC , Canada
| | - Ian Gold
- Departments of Psychiatry and Philosophy, McGill University , Montreal, QC , Canada
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Tajkarimi K, Burnett AL. The Role of Genital Nerve Afferents in the Physiology of the Sexual Response and Pelvic Floor Function. J Sex Med 2011; 8:1299-312. [DOI: 10.1111/j.1743-6109.2011.02211.x] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Kumar V, Madabushi R, Derendorf H, Boothby LA, Breland BD, Hatton RC, Doering PL. Development and Validation of an HPLC Method for Oxytocin in Ringer's Lactate and its Application in Stability Analysis. J LIQ CHROMATOGR R T 2007. [DOI: 10.1080/10826070600864742] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
Affiliation(s)
- Vipul Kumar
- a Department of Pharmaceutics, College of Pharmacy , University of Florida , Gainesville, FL, USA
| | - Rajanikanth Madabushi
- a Department of Pharmaceutics, College of Pharmacy , University of Florida , Gainesville, FL, USA
| | - Hartmut Derendorf
- a Department of Pharmaceutics, College of Pharmacy , University of Florida , Gainesville, FL, USA
| | - Lisa A. Boothby
- b Drug Information Services , Columbus Regional Healthcare System , Columbus, Georgia, USA
| | - Burnis D. Breland
- b Drug Information Services , Columbus Regional Healthcare System , Columbus, Georgia, USA
| | - Randy C. Hatton
- c SHANDS Drug Information and Pharmacy Resource Center, College of Pharmacy , University of Florida , Gainesville, Florida, USA
| | - Paul L. Doering
- c SHANDS Drug Information and Pharmacy Resource Center, College of Pharmacy , University of Florida , Gainesville, Florida, USA
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Lee SY, Kim MT, Jee SH, Yang HP. Does long-term lactation protect premenopausal women against hypertension risk? A Korean women's cohort study. Prev Med 2005; 41:433-8. [PMID: 15917038 DOI: 10.1016/j.ypmed.2004.11.025] [Citation(s) in RCA: 63] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/29/2003] [Revised: 08/02/2004] [Accepted: 11/18/2004] [Indexed: 11/22/2022]
Abstract
BACKGROUND Little is known about the long-term effect of lactation on maternal cardiovascular health except for a few animal or human experimental studies. The objective of this study was to examine the effects of lactation on the incidence of hypertension in premenopausal women. METHODS The data were derived from a cohort study with 6 years follow-up (1995-2000). The cohort was composed of 177,749 Korean premenopausal women, aged 20-59, who had medical evaluations in 1992 and 1994. During the follow-up, blood pressure was measured as part of the 1996, 1998, and 2000 periodic examinations. RESULTS In multivariate Cox proportional hazard models, lactation decreased the risk of hypertension (risk ratio, 0.92; 95% confidence interval, 0.90-0.96). Compared with women who with no history of lactation, 1-6 months of lactation decreased the risk of hypertension (RR, 0.90; 95% CI, 0.87-0.93), as did 7-12 months (RR, 0.92; 95% CI, 0.87-0.98) or 13-18 months (RR, 0.93; 95% CI, 0.86-0.99). In particular, the coexistence of obesity and no lactation increased the risk of hypertension (P for interaction = 0.028). CONCLUSION This finding suggests that lactation may be a protective factor against hypertension among premenopausal women.
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Affiliation(s)
- Soon Young Lee
- Department of Preventive Medicine and Public Health, School of Medicine, Ajou University, Yeounton-gu, Suwon 443-721, Republic of Korea.
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Light KC, Grewen KM, Amico JA, Brownley KA, West SG, Hinderliter AL, Girdler SS. Oxytocinergic activity is linked to lower blood pressure and vascular resistance during stress in postmenopausal women on estrogen replacement. Horm Behav 2005; 47:540-8. [PMID: 15811355 DOI: 10.1016/j.yhbeh.2004.12.010] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/13/2004] [Revised: 10/29/2004] [Accepted: 12/21/2004] [Indexed: 01/29/2023]
Abstract
Estrogen administration results in increased release of the oxytocin (OT) prohormone reflected by increases in oxytocin intermediate peptide (OT Int) in both animal models and humans, and sequential treatment of ovariectomized rats with estrogen/progesterone then progesterone withdrawal leads to increased hypothalamic OT mRNA. Blood pressure (BP) reductions have been related to increased exogenous and endogenous OT in rats and to higher endogenous OT activity in premenopausal women, but not previously in postmenopausal women. Thus, we used plasma obtained at rest and during a speech stressor from 54 postmenopausal women who participated in a 6-month randomized trial of oral conjugated estrogens vs. placebo to examine effects of estrogen replacement therapy (ERT) on plasma OT and OT Int levels and their relationships to changes in BP during the trial. ERT alone and with progesterone (but not placebo) led to significant increases in plasma levels of OT Int, but no change in plasma OT levels. Women showing greater increases in OT Int during treatment showed greater decreases in BP and total vascular resistance during a series of behavioral stressors compared to women with moderate or no increases in OT Int, even after controlling for effects related to treatment condition or to changes in plasma estradiol. The findings suggest that enhanced oxytocinergic activity may contribute to BP decreases associated with ERT in more responsive postmenopausal women.
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Affiliation(s)
- Kathleen C Light
- School of Medicine, University of North Carolina at Chapel Hill, NC 27599-7175, USA.
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10
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Abstract
Self-reports of mothers currently breast-feeding (n = 561) and mothers who had breast-fed in the past (n = 452) were compared for perceived stress, self-reports of upper respiratory infection symptoms, and physician visits for psychological illnesses. Possible demographic confounds were controlled statistically. In analyses examining breast-feeding status as a dichotomous variable (current vs. past), breast-feeding was negatively associated with perceived stress and upper respiratory symptoms (the latter association dissolved when controlling for perceived stress), but not with physician visits for psychological illnesses. However, analyses of the continuous variables of frequency of breast-feeding and cumulative amount of breast-feeding revealed negative associations, and analyses of times since last nursing revealed positive associations with likelihood for physician visits for psychological illnesses. Frequency of bottle-feeding was positively associated with perceived stress. The results support the interrelatedness of breast-feeding and maternal health in online mothers.
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Abstract
Oxytocin receptors have recently been demonstrated in human osteoblast-like (hOB) cells. In this study, oxytocin 100-1000 pmol/l increased cell proliferation of primary cultures of hOB cells, measured by [3H]thymidine incorporation, (P<0.01). In human osteosarcoma cell-line (SaOS-2), oxytocin 100 pmol/l increased cell proliferation (measured by [3H]thymidine incorporation and a commercially available kit) and protein synthesis ([3H]proline incorporation) (P<0.05). The increase in cell proliferation was abolished when SaOS-2 cells were incubated with an oxytocin antagonist and oxytocin. Oxytocin 100 pmol/l decreased interleukin-6 (IL-6) production of the hOB cells (23.4+/-1.96 versus 33.4+/-2.65 pg/well; P<0.001). These findings indicate that oxytocin may affect bone metabolism in humans.
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Affiliation(s)
- Maria Petersson
- Department of Molecular Medicine, Endocrine and Diabetes Unit, Karolinska Institutet and Karolinska Hospital, S-171 76, Stockholm, Sweden.
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Liu Y, Curtis JT, Fowler CD, Spencer C, Houpt T, Wang ZX. Differential expression of vasopressin, oxytocin and corticotrophin-releasing hormone messenger RNA in the paraventricular nucleus of the prairie vole brain following stress. J Neuroendocrinol 2001; 13:1059-65. [PMID: 11722702 DOI: 10.1046/j.1365-2826.2001.00729.x] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
Forced swimming, as an effective stressor, has been found to facilitate the development of pair bonds in male but to interfere with this behaviour in female prairie voles (Microtus ochrogaster). In the present study, we found that forced swimming differentially influenced the expression of messenger RNA for vasopressin, oxytocin and corticotrophin-releasing hormone (CRH) in the paraventricular nucleus of the hypothalamus (PVN) in the prairie vole brain. Forced swimming did not alter vasopressin mRNA labelling, but did induce a sustained decrease in oxytocin mRNA labelling and a progressive increase in CRH mRNA labelling in the PVN. The elevated CRH mRNA labelling appeared to be due to an increased number of cells synthesizing CRH mRNA and an enhanced ability of individual cells to produce CRH mRNA. Male and female prairie voles did not differ in the vasopressin, oxytocin or CRH mRNA expression either at the basal levels or in response to swimming stress. Together, these data indicate that the hypothalamic response of vasopressin, oxytocin and CRH messenger RNAs to swimming stress is regulated by distinct transcriptional factors. In addition, it seems unlikely that these changes are involved directly in the sex differences in pair bond formation.
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Affiliation(s)
- Y Liu
- Department of Psychology, Neuroscience Program, Florida State University, Tallahassee, FL 32306, USA
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Mezzacappa ES, Guethlein W, Vaz N, Bagiella E. A preliminary study of breast-feeding and maternal symptomatology. Ann Behav Med 2001; 22:71-9. [PMID: 10892531 DOI: 10.1007/bf02895170] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
Abstract
The association between breast-feeding status and maternal health is examined. A survey questionnaire was presented via the World Wide Web. Self-reports of 168 breast-feeding and 65 weaned mothers between 4 and 208 weeks postpartum were compared for physician visits, symptomatology, and Perceived Stress Scale scores in the last month. Breast-feeding was associated with fewer physician visits and symptoms and less perceived stress. Moreover, the longer a woman breast-fed before she weaned, the fewer the symptoms and less stress she reported. Breast-feeding is associated with better maternal health both during the breast-feeding period and after weaning. Further research on the effects on maternal health of breast-feeding is indicated. Future prospective longitudinal investigations should address the possible inhibition of lactation by stress and physiological mechanisms that may link breast-feeding and weaning with maternal health.
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Light KC, Smith TE, Johns JM, Brownley KA, Hofheimer JA, Amico JA. Oxytocin responsivity in mothers of infants: a preliminary study of relationships with blood pressure during laboratory stress and normal ambulatory activity. Health Psychol 2000; 19:560-7. [PMID: 11129359 DOI: 10.1037/0278-6133.19.6.560] [Citation(s) in RCA: 108] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
The neuropeptide oxytocin (OT) enhances maternal behavior and decreases blood pressure (BP) and stress responses in animals. Thus, the relationship of OT responsivity to BP in 14 breast- and 11 bottle-feeding mothers of infants was examined. Laboratory BP was assessed during baseline, speech preparation, active speech, and recovery on 2 days, 1 in which baseline and speech were separated by 10 min of baby holding and the other by no baby contact. Systolic BP reactivity to speech was lower after baby contact. Plasma OT change from baseline to speech after baby contact defined OT increase, minimal OT change, and OT decrease groups. OT increase mothers were primarily breast-feeders, and they had lower BP throughout both stress sessions and after baby feeding at home than OT decrease mothers, who also had greater BP reactivity to preparation and recovery. These results suggest that oxytocin has antistress and BP-lowering effects in humans.
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Affiliation(s)
- K C Light
- Department of Psychiatry, University of North Carolina at Chapel Hill, 27599-7175, USA.
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15
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Norepinephrine-induced inhibition of thyroid-stimulating effects of oxytocin in rats. Bull Exp Biol Med 1999. [DOI: 10.1007/bf02434825] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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Mezzacappa ES. A preliminary study of the effects of breast-feeding on maternal health. Int J Behav Med 1997; 4:230-41. [PMID: 16250730 DOI: 10.1207/s15327558ijbm0403_3] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
This study is a preliminary investigation of the effects on breast-feeding and cessation of breast-feeding on maternal health. A self-report questionnaire assessed overall health, mood, stress, and psychological and upper respiratory infection symptoms in 14 current, 36 never, and 49 past breast-feeders. Results indicated that breast-feeding did not incur greater health costs to the mother compared with bottle-feeding and that cessation of breastfeeding was associated with worse mood, more stress, and a greater number of psychological symptoms compared with current breast-feeding. Physiological mechanisms, as opposed to personality factors, are discussed as a basis for these findings.
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Affiliation(s)
- E S Mezzacappa
- Behavioral Medicine Program, Columbia-Presbyterian Medical Center, New York, NY, USA.
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18
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Laorden ML, Milanés MV, Chapleur-Château M, Burlet A. Changes in hypothalamic oxytocin levels during morphine tolerance. Neuropeptides 1997; 31:143-6. [PMID: 9179867 DOI: 10.1016/s0143-4179(97)90083-4] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
The role of hypothalamic oxytocin neurons in the hypothalamus-pituitary-adrenal (HPA) axis adaptation during opioid tolerance has not been explored. In this study the modification of oxytocin levels in different hypothalamic nuclei was determined after acute or chronic morphine exposure. Male rats were implanted with placebo (naïve) or morphine (tolerant) pellets for 7 days. On day 8, groups of rats received an acute injection of either saline i.p. or morphine (30 mg/kg i.p.) and were sacrificed 30 min later. In morphine-tolerant rats, there was a decrease in the oxytocin content in the median eminence (ME) and in the supraoptic nucleus (SO) after acute injection of saline or morphine. No modifications were seen in the paraventricular nucleus (PVN). The present study demonstrates that chronic morphine administration alters the brain oxytocin system, which suggests that this peptide might contribute to the behavioural, emotional and neuroendocrine responses to opioids.
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Affiliation(s)
- M L Laorden
- Department of Physiology and Pharmacology, University School of Medicine, Murcia, Spain
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Affiliation(s)
- R M Freidinger
- Department of Medicinal Chemistry, Merck Research Laboratories, West Point, Pennsylvania 19486, USA
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Yanagimoto M, Honda K, Goto Y, Negoro H. Afferents originating from the dorsal penile nerve excite oxytocin cells in the hypothalamic paraventricular nucleus of the rat. Brain Res 1996; 733:292-6. [PMID: 8891313 DOI: 10.1016/0006-8993(96)00800-1] [Citation(s) in RCA: 46] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
Electrical stimulation of the dorsal penile nerve (DPN) produced orthodromic excitation in about half of oxytocin cells in the paraventricular nucleus (PVN). In contrast, less than 10% of vasopressin cells were excited. Tactile stimulation of the glans penis by a paintbrush produced excitation in 40% of oxytocin cells. Castration did not prevent activation of oxytocin cells. These results suggest that somatosensory information from the penis is transmitted to the PVN through the DPN and that such afferent input preferentially innervates oxytocin cells.
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Affiliation(s)
- M Yanagimoto
- Department of Anesthesiology and Reanimatology, Fukui Medical School, Japan
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21
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Sun Q, Pretel S, Applegate CD, Piekut DT. Oxytocin and vasopressin mRNA expression in rat hypothalamus following kainic acid-induced seizures. Neuroscience 1996; 71:543-54. [PMID: 9053806 DOI: 10.1016/0306-4522(95)00466-1] [Citation(s) in RCA: 23] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
In this study, the regulation of hypothalamic oxytocin and vasopressin messenger RNA expression following the induction of seizures was investigated by in situ hybridization. Following kainic acid-induced seizures, a significant increase in oxytocin messenger RNA in the paraventricular nucleus was demonstrated at 1.5 h, one and two weeks; its level decreased at three weeks and was significantly increased again at four weeks; at eight weeks the messenger RNA level still remained higher than that of controls. Vasopressin messenger RNA in the paraventricular nucleus was increased significantly only at 1.5 h following induction of seizures. The oxytocin messenger RNA level in the supraoptic nucleus was also increased early at 1.5 h and later at four weeks following seizures; however, these increases did not last as long as those in the paraventricular nucleus. Vasopressin messenger RNA in the supraoptic nucleus was also increased after the initial seizures; however, its messenger RNA level vacillated up and down throughout the post-seizure times studied. The earliest significant increase of vasopressin messenger RNA was at one week after seizures, and there was a late significant increase of vasopressin messenger RNA at three weeks after seizures. The present study demonstrates that following kainic acid-induced seizures both, the oxytocin and vasopressin messenger RNA expressions, were up-regulated and these up-regulations were long-term events. The increase of oxytocin messenger RNA in the paraventricular nucleus was more persistent than the others. The pattern of messenger RNA up-regulation was different for oxytocin and vasopressin, and different in the paraventricular nucleus and supraoptic nucleus. These different patterns of messenger RNA elevations suggest that the different components of the rat hypothalamus were regulated differentially by kainic acid-induced seizures.
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Affiliation(s)
- Q Sun
- Department of Neurobiology and Anatomy, University of Rochester, NY 14642, USA
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22
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Abstract
Though oxytocin and vasopressin are similar in structure and are produced in the same brain regions, they show specific responses under stress conditions. In humans, increases in peripheral blood vasopressin appear to be a consistent finding during many acute stress situations, while in rats, vasopressin secretion is unresponsive to several stimuli known to induce ACTH and catecholamine release. Even decreases in vasopressin levels during stress were described. In accordance with others, we observed enhanced vasopressin release in response to stress stimuli with an osmotic component such as hypertonic saline injection but also during exposure of rats to a warm environment. Immobilization stress which fails to induce vasopressin release was reported to increase hypothalamic vasopressin mRNA and plasma vasopressin levels in chronically adreno-demedullated rats. Unlike vasopressin, oxytocin may be considered a typical stress hormone responding to osmotic as well as other stress stimuli. We found that acute exposure of rats to immobilization stress resulted in an increase in oxytocin mRNA level. In addition, we have shown that magnocellular neurons of the paraventricular nucleus, but not the supraoptic nucleus, are essential for oxytocin release during immobilization stress. The release of posterior pituitary hormones represents an important component of the stress response.
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Affiliation(s)
- D Jezova
- Institute of Experimental Endocrinology, Slovak Academy of Sciences, Bratislava, Slovakia
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23
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Stachowiak A, Macchi C, Nussdorfer GG, Malendowicz LK. Effects of oxytocin on the function and morphology of the rat adrenal cortex: in vitro and in vivo investigations. RESEARCH IN EXPERIMENTAL MEDICINE. ZEITSCHRIFT FUR DIE GESAMTE EXPERIMENTELLE MEDIZIN EINSCHLIESSLICH EXPERIMENTELLER CHIRURGIE 1995; 195:265-74. [PMID: 8578002 DOI: 10.1007/bf02576797] [Citation(s) in RCA: 26] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
The effects of oxytocin (OX) on the function and morphology of the rat adrenal cortex were studied in vivo and in vitro. OX exerted a potent stimulatory action on basal, but not 10(-8) M ACTH-stimulated corticosterone (B) secretion of dispersed rat inner (zona fasciculata and zona reticularis) adrenocortical cells (maximal effective concentration: 10(-9) M); in contrast, at higher concentrations (10(-7)/10(-6) M) OX inhibited maximally ACTH-stimulated B output. A single subcutaneous (s.c.) injection of 1.2 nmol/100 g body weight OX resulted in a long-lasting (up to 12 h) rise in plasma B concentration (PBC). The prolonged administration of OX (daily s.c. injections of 0.6 or 1.2 nmol/100 g for 10 days) caused a marked lowering in the adrenal weight and volume of all adrenocortical zones, that in turn was due to a decrease in the number of their parenchymal cells; however, the average volume of inner adrenocortical cells was significantly increased. Basal PBC was lowered, but its response to ether stress was unchanged in comparison with control rats. Prolonged OX treatment did not change B secretion by adrenal slices, but it markedly raised that of dispersed inner adrenocortical cells. Our present findings clearly show that the effects of OX on the adrenal cortex depend on the experimental model employed (in vitro versus in vivo) and the duration of treatment (acute versus chronic). Taken together they allow us to conclude that OX exerts an acute direct stimulatory effect on the rat adrenal cortex, and a chronic inhibitory one, that at least in part could be due to the interference of OX with the mechanism(s) of intracellular transduction of the ACTH secretagogue signal.
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Affiliation(s)
- A Stachowiak
- Department of Histology and Embryology, School of Medicine, Poznan, Poland
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24
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Manning M, Miteva K, Pancheva S, Stoev S, Wo NC, Chan WY. Design and synthesis of highly selective in vitro and in vivo uterine receptor antagonists of oxytocin: comparisons with Atosiban. INTERNATIONAL JOURNAL OF PEPTIDE AND PROTEIN RESEARCH 1995; 46:244-52. [PMID: 8537178 DOI: 10.1111/j.1399-3011.1995.tb00596.x] [Citation(s) in RCA: 77] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
We report the solid phase synthesis and some pharmacological properties of seven position two analogues (peptides 1-7) of one of our lead oxytocin antagonists, des-9-glycinamide[1-(beta-mercapto-beta,beta-pentamethylenepropionic+ ++ acid),2-O-methyltyrosine,4-threonine]ornithinevasotocin(desGly+ ++-NH2, d(CH2)5-[Tyr(Me)2,Thr4]OVT) (A). Peptides 1-7 have the following substituents at position two (1) D-Tyr(Me); (2) L-Tyr(Et); (3) D-Tyr(Et); (4) L-Tyr; (5) D-Tyr; (6) D-Phe and (7) D-Trp. These were evaluated for agonistic and antagonistic activities in in vitro and in vivo OT assays, in vivo vasopressor (V1a-receptor) assays and in vivo antidiuretic (V2-receptor) assays. None of the seven peptides exhibits oxytocic or vasopressor agonism. Peptides 1, 2, 4, 6 and 7 are extremely weak V2 agonists (V2 activities range from 0.001 to 0.02 U/mg). Peptides 3 and 5 exhibit weak V2 antagonism (pA2 < 6.0 and < 5.5, respectively). Peptides 1-7 exhibit potent in vitro (no Mg2+) OT antagonism (anti-OT pA2 values range from 7.66 to 8.03). Peptides 1 and 4-7 exhibit potent in vivo OT antagonism. Estimated in vivo anti-OT pA2 values range from 7.06 to 7.79 (peptides 2 and 3 were not tested). With anti-V1a pA2 values of 5.17-6.25 all seven peptides exhibit reduced anti-V1a potencies relative to the parent peptide (A) (anti-V1a pA2 = 6.46). Four of these peptides (4-7) exhibit striking gains in in vitro and in vivo anti-OT/anti-V1a selectivities compared to (A) which has an in vitro selectivity of 30 and an in vivo selectivity of 18. The D-Tyr2 (5), D-Trp2 (7), D-Phe2 (6) and L-Tyr2 (4) analogues of (A) exhibit anti-OT (in vitro)/anti-V1a selectivities = 240, 390, 404 and 540, respectively. The L-Tyr2 (4), D-Trp2 (7), D-Phe2 (6) and D-Tyr2 (5) analogues exhibited anti-OT (in vivo)/anti-V1a selectivities of 72, 80, 88 and 95, respectively. Peptides 4-7 appear to be the most selective peptide OT antagonists reported to date. In this regard it may be noted that they appear to be as or more potent and much more selective than the closely related OT antagonist 1-deamino[D-Tyr(Et)2,Thr4]OVT (Atosiban) which is currently undergoing clinical trial as a potential therapeutic agent for the prevention of premature labor. Atosiban (peptide 8) was resynthesized and pharmacologically evaluated in our laboratories. Atosiban exhibits the following antagonistic potencies. Anti-OT (in vitro, no Mg2+) pA2 = 7.71; anti-OT in vivo pA2 = 7.05; anti-V1a pA2 = 6.14 and anti-V2 pA2 approximately 5.9. Its anti-OT (in vivo)/anti-V1a selectivity is 8. Some of these antagonists may be suitable candidates for evaluation as potential tocolytic agents for use in the treatment of pre-term labor. They could also serve as useful new pharmacological tools for studies on the physiological roles of oxytocin. Finally, the findings presented here provide useful clues for the design of more potent and more selective OT antagonists.
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Affiliation(s)
- M Manning
- Department of Biochemistry and Molecular Biology, Medical College of Ohio, Toledo, USA
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25
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Lawrence A, Petherick J, McLean K, Deans L, Chirnside J, Vaughan A, Gilbert C, Forsling M, Russell J. The effects of chronic environmental stress on parturition and on oxytocin and vasopressin secretion in the pig. Anim Reprod Sci 1995. [DOI: 10.1016/0378-4320(94)01361-o] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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26
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Misharina GV, Volkov AV. Improved recovery of neurologic status by oxytocin after 10-min cardiac arrest in rats. Bull Exp Biol Med 1994. [DOI: 10.1007/bf02444285] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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27
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Role of oxytocin in the regulation of feeding behavior of young mammals during the lactotrophic period. Bull Exp Biol Med 1994. [DOI: 10.1007/bf02444202] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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28
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Kukucka MA, Misra HP. Determination of oxytocin in biological samples by isocratic high-performance liquid chromatography with coulometric detection using C18 solid-phase extraction and polyclonal antibody-based immunoaffinity column purification. JOURNAL OF CHROMATOGRAPHY. B, BIOMEDICAL APPLICATIONS 1994; 653:139-45. [PMID: 8205241 DOI: 10.1016/0378-4347(93)e0414-l] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
A specific high-performance liquid chromatographic (HPLC) method is described for the reliable quantitation of oxytocin using culture media supernatants. The procedure employs solid-phase extraction, antibody-based immunoaffinity purification and isocratic HPLC with dual channel coulometric detection (ED). The lower limit of detection for this cyclic nonapeptide was 40 pg (40 fmol). Due to its relative simplicity, specificity and precision, the HPLC-ED of oxytocin is an accurate and attractive alternative to many existing quantitative methods.
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Affiliation(s)
- M A Kukucka
- Department of Biomedical Sciences, Virginia-Maryland Regional College of Veterinary Medicine, Virginia Polytechnic Institute and State University, Blacksburg 24061-0442
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29
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Daddona MM, Haldar J. The release of oxytocin from spinal cord synaptosomes by high KCl depolarizing stimulus: a calcium dependent process. Life Sci 1994; 54:945-9. [PMID: 8139384 DOI: 10.1016/0024-3205(94)00495-1] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
Oxytocin (OT) release from synaptosomes isolated from the thoracic (T) and lumbosacral (LS) regions of the spinal cord was evoked by 56 mM potassium chloride (KCl). The release mechanism was shown to be a calcium dependent process. The ability of high KCl to evoke OT release from isolated nerve terminals in a calcium dependent manner provides additional support for the role of OT as a neurotransmitter in the spinal cord.
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Affiliation(s)
- M M Daddona
- Department of Biological Sciences, St. John's University, Jamaica, New York 11439
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30
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Reuss S, Mattern E, Spessert R, Riemann R, Weber A, Vollrath L. Lack of effect of oxytocin on the numbers of "synaptic" ribbons, cyclic guanosine monophosphate and serotonin N-acetyltransferase activity in organ-cultured pineals of three strains of rats. Cell Tissue Res 1993; 274:337-42. [PMID: 8269481 DOI: 10.1007/bf00318752] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
In addition to the stimulating influence of the sympathetic system on the function of the mammalian pineal gland, neuropeptides such as neuropeptide Y, vasoactive intestinal polypeptide and arginine-vasopressin (AVP) are thought to function as modulators. Since AVP has been shown to influence pineal melatonin synthesis, the aim of the present study was to investigate the possible effects of the second hypothalamic nonapeptide oxytocin (OT), which likewise has been detected in the pineal gland. We therefore studied "synaptic" ribbon (SR) numbers, N-acetyltransferase (NAT) activity and the intracellular concentration of cyclic guanosine monophosphate (cGMP) following in vitro incubation of rat pineals in media containing OT (10(-5) M), noradrenaline (NA, 10(-5) M) or both NA and OT. Pineal glands were derived from rats of three different strains (Sprague-Dawley, Long-Evans and the AVP-deficient strain Brattleboro). Neither morphological nor biochemical analyses showed a difference between control and OT-incubated organs in any of the strains tested. In Brattleboro rats, but not in the other strains, noradrenaline slightly increased the number of SR which was not observed when NA and OT were combined. The addition of NA resulted in distinct augmentation of NAT activity and cGMP content, which were not affected by additional OT application. These results suggest that oxytocin is not crucially involved in the regulation of pineal gland function.
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Affiliation(s)
- S Reuss
- Department of Anatomy, Johannes Gutenberg University, Mainz, Germany
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31
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Melin P. Oxytocin antagonists in preterm labour and delivery. BAILLIERE'S CLINICAL OBSTETRICS AND GYNAECOLOGY 1993; 7:577-600. [PMID: 8252818 DOI: 10.1016/s0950-3552(05)80449-3] [Citation(s) in RCA: 28] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
Evidence has been gained that an oxytocin receptor antagonist given by intravenous infusion effectively stops uterine contractions in threatened as well as in actual preterm labour. The findings suggest that the increase of oxytocin receptors is aetiologically important in uncomplicated preterm labour. Oxytocin antagonists could therefore be an attractive alternative to currently used drugs by virtue of their high specificity and lack of serious side-effects. Their use in prophylactic and maintenance therapy may be greater when modified analogues have been developed that allow non-parenteral therapy.
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Affiliation(s)
- P Melin
- Ferring Research Institute AB, Malmö, Sweden
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32
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Affiliation(s)
- P Melin
- Ferring Research Institute AB, Malmö, Sweden
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33
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Chiodera P, Volpi R, Caiazza A, Davoli C, Marchesi C, Papadia C, Capretti L, Bocchi R, Coiro V. Inhibitory effect of dexamethasone on the oxytocin response to insulin-induced hypoglycemia in normal men. J Endocrinol Invest 1992; 15:459-63. [PMID: 1328351 DOI: 10.1007/bf03348773] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Glucocorticoids are known to reduce both ACTH and arginine vasopressin responses to insulin-induced hypoglycemia in normal men. The present study was undertaken in order to establish whether glucocorticoids are capable of modifying the oxytocin (OT) response to hypoglycemia. For this purpose, 8 normal men (28-33 yr) were tested with insulin (0.15 IU/kg in an iv bolus) [insulin tolerance test (ITT)] with and without pretreatment with dexamethasone (2 or 4 mg in an iv bolus 10 min before insulin). Eight different subjects (29-35 yr) were tested with dexamethasone alone. The administration of dexamethasone (2 or 4 mg) alone changed neither ACTH nor OT concentrations in the plasma during the next hour. Insulin produced similar hypoglycemic responses, regardless of dexamethasone treatment. ACTH levels rose significantly in response to insulin-induced hypoglycemia, with a mean peak response at 45 min (p less than 0.01 vs baseline). Two and four mg dexamethasone produced similar significant reductions of the ACTH response to hypoglycemia (p less than 0.02 at 45 min, p less than 0.05 at 30 and 60 min vs ITT). In the ITT, OT levels rose significantly in response to hypoglycemia, with a mean peak response at 45 min (p less than 0.01 vs basal value). The pretreatment with 2 or 4 mg dexamethasone reduced in a similar manner the hypoglycemia-induced OT rise (p less than 0.05 at 30 and 45 min vs ITT). These findings show a partial inhibition by dexamethasone of the OT response to hypoglycemia.(ABSTRACT TRUNCATED AT 250 WORDS)
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Affiliation(s)
- P Chiodera
- Cattedra di Endocrinologia e Patologia Costituzionale, Università di Parma, Italy
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