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AIM: To describe the implementation and evaluation of a midwife/midwifery student-mentoring program in one Local Health District in Sydney NSW Australia. BACKGROUND: Evidence suggests well designed and supported midwife/midwifery student mentorship programs can make a difference to the clinical placement experiences and attrition rates of midwifery students. DESIGN: In the evaluation of the mentoring program, we used surveys, focus groups and individual interviews. METHODS: Eighty-six participants, including midwife mentors, midwifery students, non-mentor midwives and midwifery managers participated in the evaluation. Quantitative data were analysed using descriptive statistics and qualitative data, content analysis. RESULTS: The mentoring program increased midwives' mentoring skills and was beneficial to their professional growth and leadership skills. Students reported positive outcomes including someone to talk to, emotional support and a sense of belonging. Mentoring programs require structure, mentor training, organisational support and transparency. CONCLUSION: The mentoring program provided benefits to both midwifery mentors and students and demonstrated the value of a structured and supported mentoring program for midwifery students.
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Tutoría , Partería , Humanos , Partería/educación , Estudiantes de Enfermería , Evaluación de Programas y Proyectos de Salud , Desarrollo de Programa , Enfermeras Obstetrices/educación , Liderazgo , Investigación CualitativaRESUMEN
BACKGROUND: Maternity care in Australia is predominantly provided by midwives, many who give birth. There is a paucity of research on midwives' own childbearing preferences and experiences. AIM: To explore midwives childbirth preferences and outcomes when giving birth to their first child in Australia, after qualifying as a midwife. METHODS: An online national survey. Data were analysed using descriptive statistics. FINDINGS: 447 midwives responded, with the majority of midwives indicating a preference for a normal vaginal birth with a known care provider under a continuity of midwifery care model. For midwives who were first time mothers, 66% had normal vaginal births, 16.3% had an instrumental birth, and 16.8% had caesarean births. Over 85% of midwives received the model of care they wanted and 45% had continuity of midwifery care. While a quarter of midwives wanted a homebirth,11.2% achieved this. Over three quarters (75.4%) of midwives were cared for by a care provider of their choosing. DISCUSSION: There was a difference in models of care accessed and birth outcomes between midwives and other women giving birth for the first-time in Australia. Australian midwives appear to have the advantage of clinical and scientific knowledge to navigate the maternity care system to get the birth care and outcomes they want. CONCLUSION: It is possible that professional experience, insider knowledge, and existing relationships with other midwifery friends and colleagues, affords midwives a higher degree of agency and autonomy when it comes to getting the maternity care and birth outcomes that they want.
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Servicios de Salud Materna , Partería , Enfermeras Obstetrices , Niño , Embarazo , Femenino , Humanos , Australia , Parto , Parto ObstétricoRESUMEN
BACKGROUND: The majority of maternity care is provided by female midwives who have either become mothers or are of childbearing age, but there is limited research exploring midwives' own personal childbearing experiences. This integrative review aims to explore the published literature and research on midwives' own experiences of pregnancy and childbirth. METHOD: An integrative review of the literature was conducted after relevant articles were identified through a search of: five electronic databases (Cumulative Index of Nursing and Allied Health Literature (CINAHL), Medline, PubMed, Scopus, and Google Scholar), cited reference lists, and networking with peers. Similar and contrasting patterns and relations within the literature were identified and grouped into themes and subthemes. RESULTS: Twenty articles were included in the review and four overarching themes were identified. Insider knowledge plays a role in decision making encompassed the way midwives used their knowledge to choose; a preferred mode of birth, maternity care provider, model of care, and place of birth. Navigating the childbirth journey demonstrated how some midwives were able to use their insider knowledge to achieve agency, while others had difficulty achieving agency. This theme also revealed the 'midwife brain' that midwives need to manage during their childbearing journey. The theme impact of care on the birth experience described how the type of care the midwives received from maternity care providers affected their overall birth experience. The fourth theme from midwife to mother explains their preparedness for childbirth and their transition to motherhood. CONCLUSION: For childbearing midwives, there is a potential conflict between their position as knowledgeable experts in maternity care, and their experience as mothers. Whilst they can use their insider knowledge to their advantage, they also experience heightened fear and anxiety through their pregnancy. It is important for maternity care providers to acknowledge and support them and provide balanced and tailored care that acknowledges the woman within the professional midwife and the professional midwife within the woman.
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Servicios de Salud Materna , Partería , Enfermeras Obstetrices , Parto Obstétrico , Femenino , Humanos , Parto , Embarazo , Investigación CualitativaRESUMEN
An amendment to this paper has been published and can be accessed via the original article.
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BACKGROUND: Severe perineal trauma sustained during childbirth is a serious complication since it can lead to both short- and long-term consequences for women. Some of the methods used to prevent perineal injuries have been evaluated in clinical trials, but there are still gaps in the evidence. A new clinical practice has been introduced, adopted by more than half of the maternity wards in Sweden with the aim of reducing severe perineal trauma. This procedure involves two midwives assisting the woman during the second stage of labour. METHODS/DESIGN: In this multicentre randomised controlled trial, 2946 women will be randomised to be assisted by one or two midwives during the second stage of labour. Women age 18-47, who plan for their first vaginal birth, with a singleton pregnancy in cephalic presentation, will be asked to participate when admitted to the maternity ward. Five maternity wards comprising 19,500 births/year in different parts of Sweden will participate in this study. The sample size is powered to demonstrate a 50% reduction (from 4.1-2.0%) in primary outcome, which is the prevalence of severe perineal trauma (3rd and 4th degree). Secondary outcomes will include maternal and neonatal outcomes, women's experiences, midwives' experiences of the intervention, incontinence, and pelvic floor symptoms. The primary analysis is intention to treat. Questionnaires will be sent to the women at 1 month and 1 year after the birth to assess women's experiences, pain, incontinence, pelvic floor symptoms, sexual function, and mental health. DISCUSSION: It is important for care during labour and birth to be evidence based. There is a strong desire among midwives to reduce the risk of severe perineal trauma. This may lead to new strategies and practices being implemented into practice without scientific evidence. The intervention might have negative side effects or unintended consequences. On the other hand, there is a possibility of the intervention improving care for women. TRIAL REGISTRATION {2A}: ClinicalTrials.gov NCT03770962 . Registered on 10 December 2018.
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Trabajo de Parto , Perineo , Adolescente , Adulto , Parto Obstétrico , Femenino , Humanos , Recién Nacido , Persona de Mediana Edad , Estudios Multicéntricos como Asunto , Parto , Embarazo , Ensayos Clínicos Controlados Aleatorios como Asunto , Suecia , Adulto JovenRESUMEN
BACKGROUND: Pregnant women in Australia seldom seek dental care and are unaware of its importance. To address these gaps the midwifery-initiated oral health dental service (MIOH-DS) program was comprehensive trialled and found effective. The aim of this study was to undertake a process evaluation of the MIOH-DS using the perspectives of pregnant women who participated in the trial. METHODS: A qualitative research design was utilized, whereby content analysis was undertaken on data from 11 semi-structured interviews with women who participated in the program. RESULTS: All participants were receptive of the MIOH-DS intervention, and found it to be an acceptable intervention that met their needs, and encouraged future positive oral health practices and health-seeking behaviours. They expressed that midwives were an appropriate professional to conduct oral health assessments, education and referrals to affordable dental services. Although some participants were initially apprehensive towards receiving treatment during pregnancy, dental staff members were able to appropriately educate and reassure them during treatment. CONCLUSIONS: The MIOH-DS represents a promising and acceptable intervention strategy for pregnant women to promote their oral health. Findings merit further investigation on whether positive outcomes achieved can be sustained when implemented in other national or international settings similar to the study setting.
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Servicios de Salud Dental/organización & administración , Partería , Salud Bucal , Aceptación de la Atención de Salud , Australia , Femenino , Humanos , Partería/organización & administración , Embarazo , Evaluación de Programas y Proyectos de Salud , Derivación y ConsultaRESUMEN
BACKGROUND: Studies internationally show a lack of consensus among dentists regarding perinatal oral health yet no study in Australia has explored the perceptions of dentists in this area. This study aims to determine the knowledge, perceptions and practises of dentists in New South Wales (NSW), Australia, about perinatal oral health. METHODS: An online survey was distributed to 1357 members of the Australian Dental Association (NSW) and 185 (13.4%) completed surveys were returned. RESULTS: Most dentists (99%) stated that pregnant women should receive a dental check, yet only 20% agreed that there was a good understanding among health professionals on this topic. Dentists were aware of safe dental practises during pregnancy but had limited knowledge about the association between periodontal disease and birth outcomes. Dentists were more likely to advise pregnant women to delay dental visits when there was a perceived lack of knowledge of the risks involved (odds ratio, 2.157) or were concerned about providing treatment without consent from their general practitioner (odds ratio, 2.449). Most dentists (95.7%) stated that they wanted further information about dental care during pregnancy. CONCLUSIONS: Findings suggest a need for continuing education for dentists and practise guidelines on perinatal oral health. Further research with a national sample is recommended to confirm these findings.
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Atención Odontológica/estadística & datos numéricos , Conocimientos, Actitudes y Práctica en Salud , Salud Bucal , Pautas de la Práctica en Odontología/estadística & datos numéricos , Adulto , Anciano , Actitud del Personal de Salud , Estudios Transversales , Odontólogos/estadística & datos numéricos , Femenino , Humanos , Masculino , Persona de Mediana Edad , Nueva Gales del Sur/epidemiología , Enfermedades Periodontales/prevención & control , Embarazo , Encuestas y CuestionariosRESUMEN
OBJECTIVE: To evaluate the effect of an antenatal integrative medicine education programme in addition to usual care for nulliparous women on intrapartum epidural use. DESIGN: Open-label, assessor blind, randomised controlled trial. SETTING: 2 public hospitals in Sydney, Australia. POPULATION: 176 nulliparous women with low-risk pregnancies, attending hospital-based antenatal clinics. METHODS AND INTERVENTION: The Complementary Therapies for Labour and Birth protocol, based on the She Births and acupressure for labour and birth courses, incorporated 6 evidence-based complementary medicine techniques: acupressure, visualisation and relaxation, breathing, massage, yoga techniques, and facilitated partner support. Randomisation occurred at 24-36â weeks' gestation, and participants attended a 2-day antenatal education programme plus standard care, or standard care alone. MAIN OUTCOME MEASURES: Rate of analgesic epidural use. Secondary: onset of labour, augmentation, mode of birth, newborn outcomes. RESULTS: There was a significant difference in epidural use between the 2 groups: study group (23.9%) standard care (68.7%; risk ratio (RR) 0.37 (95% CI 0.25 to 0.55), p≤0.001). The study group participants reported a reduced rate of augmentation (RR=0.54 (95% CI 0.38 to 0.77), p<0.0001); caesarean section (RR=0.52 (95% CI 0.31 to 0.87), p=0.017); length of second stage (mean difference=-0.32 (95% CI -0.64 to 0.002), p=0.05); any perineal trauma (0.88 (95% CI 0.78 to 0.98), p=0.02) and resuscitation of the newborn (RR=0.47 (95% CI 0.25 to 0.87), p≤0.015). There were no statistically significant differences found in spontaneous onset of labour, pethidine use, rate of postpartum haemorrhage, major perineal trauma (third and fourth degree tears/episiotomy), or admission to special care nursery/neonatal intensive care unit (p=0.25). CONCLUSIONS: The Complementary Therapies for Labour and Birth study protocol significantly reduced epidural use and caesarean section. This study provides evidence for integrative medicine as an effective adjunct to antenatal education, and contributes to the body of best practice evidence. TRIAL REGISTRATION NUMBER: ACTRN12611001126909.
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Terapias Complementarias , Medicina Integrativa , Dolor de Parto , Trabajo de Parto , Manejo del Dolor , Adulto , Analgesia Epidural , Australia , Cesárea , Femenino , Humanos , Educación del Paciente como Asunto , Embarazo , Atención PrenatalRESUMEN
OBJECTIVE: to gain insight into the experiences of women, partners and midwives who participated in the Complementary Therapies for Labour and Birth Study, an evidence based complementary medicine (CM) antenatal education course. DESIGN: qualitative in-depth interviews and a focus group as part of the Complementary Therapies for Labour and Birth Study. SETTING AND PARTICIPANTS: thirteen low risk primiparous women and seven partners who had participated in the study group of a randomised controlled trial of the complementary therapies for labour and birth study, and 12 midwives caring for these women. The trial was conducted at two public hospitals, and through the Western Sydney University in Sydney, Australia. INTERVENTIONS: the Complementary Therapies for Labour and Birth (CTLB) protocol, based on the She Births® course and the Acupressure for labour and birth protocol, incorporated six evidence-based complementary medicine (CM) techniques; acupressure, relaxation, visualisation, breathing, massage, yoga techniques and incorporated facilitated partner support. Randomisation to the trial occurred at 24-36 weeks' gestation, and participants attended a two-day antenatal education programme, plus standard care, or standard care alone. FINDINGS: the overarching theme identified in the qualitative data was making sense of labour and birth. Women used information about normal birth physiology from the course to make sense of labour, and to utilise the CM techniques to support normal birth and reduce interventions in labour. Women's, partners' and midwives' experience of the course and its use during birth gave rise to supporting themes such as: working for normal; having a toolkit; and finding what works. KEY CONCLUSIONS: the Complementary Therapies for Labour and Birth Study provided women and their partners with knowledge to understand the physiology of normal labour and birth and enabled them to use evidence-based CM tools to support birth and reduce interventions. IMPLICATIONS FOR PRACTICE: the Complementary Therapies for Labour and Birth Study introduces concepts of what constitutes normal birth and provides skills to support women, partners and midwives. It appears to be an effective form of antenatal education that supports normal birth, and maternity services need to consider how they can reform current antenatal education in line with this evidence.
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Terapias Complementarias/normas , Enfermeras Obstetrices/educación , Satisfacción del Paciente , Educación Prenatal/métodos , Adulto , Australia , Femenino , Grupos Focales , Humanos , Trabajo de Parto/fisiología , Embarazo , Mujeres Embarazadas/psicologíaRESUMEN
BACKGROUND: In most high and middle income countries across the world, at least 1:4 women give birth by cesarean section. Rates of labour induction and augmentation are rising steeply; and in some countries up to 50% of laboring women and newborns are given antibiotics. Governments and international agencies are increasingly concerned about the clinical, economic and psychosocial effects of these interventions. DISCUSSION: There is emerging evidence that certain intrapartum and early neonatal interventions might affect the neonatal immune response in the longer term, and perhaps trans-generationally. Two theories lead the debate in this area. Those aligned with the hygiene (or 'Old Friends') hypothesis have examined the effect of gut microbiome colonization secondary to mode of birth and intrapartum/neonatal pharmacological interventions on immune response and epigenetic phenomena. Those working with the EPIIC (Epigenetic Impact of Childbirth) hypothesis are concerned with the effects of eustress and dys-stress on the epigenome, secondary to mode of birth and labour interventions. This paper examines the current and emerging findings relating to childbirth and atopic/autoimmune disease from the perspective of both theories, and proposes an alliance of research effort. This is likely to accelerate the discovery of important findings arising from both approaches, and to maximize the timely understanding of the longer-term consequences of childbirth practices.
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Epigénesis Genética/inmunología , Hipótesis de la Higiene , Trabajo de Parto/genética , Parto/genética , Cesárea/efectos adversos , Parto Obstétrico/efectos adversos , Parto Obstétrico/métodos , Epigenómica , Femenino , Humanos , Recién Nacido , Trabajo de Parto Inducido/efectos adversos , Trabajo de Parto Inducido/métodos , Trabajo de Parto/inmunología , Masculino , Parto/inmunología , EmbarazoRESUMEN
BACKGROUND: Reviews of maternity services highlight the need for a reduction of medical interventions for women with low risk pregnancies and births to prevent the potential cascade of interventions and their associated risks. Complementary medicines (CM) such as acupuncture and acupressure have claimed to be effective in reducing interventions in labour; however, systematic reviews of evidence to date are conflicting. AIMS: To examine current evidence from systematic reviews on the topic of acupuncture and acupressure for pain management in labour and birth, and to evaluate the methodological and treatment frameworks applied to this evidence. METHODS: A search limited to systematic reviews of the MEDLINE, CINAHL, PUBMED, EMBASE and Cochrane databases was performed in December 2013 using the keywords 'CAM', 'alternative medicine', 'complementary medicine', 'complementary therapies', 'traditional medicine', 'Chinese Medicine', 'Traditional Chinese Medicine', 'acupuncture', 'acupressure', cross-referenced with 'childbirth', 'birth', labo*r', and 'delivery'. The quality of the evidence is also evaluated in the context of study design. RESULTS: The RCTs included in these systematic reviews differed in terms of study designs, research questions, treatment protocols and outcome measures, and yielded some conflicting results. It may be inappropriate to include these together in a systematic review, or pooled analysis, of acupuncture for labour with an expectation of an overall conclusion for efficacy. Trials of acupuncture and acupressure in labour show promise, but further studies are required. CONCLUSION: The use of current systematic reviews of the evidence for acupuncture and acupressure for labour and birth may be misleading. Appropriate methods and outcome measures for investigation of acupuncture and acupressure treatment should more carefully reflect the research question being asked. The use of pragmatic trials designs with woman-centred outcomes may be appropriate for evaluating the effectiveness of these therapies.
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Acupresión , Terapia por Acupuntura , Dolor de Parto/terapia , Manejo del Dolor , Femenino , Humanos , EmbarazoRESUMEN
There are many published studies about the epigenetic effects of the prenatal and infant periods on health outcomes. However, there is very little knowledge regarding the effects of the intrapartum period (labor and birth) on health and epigenetic remodeling. Although the intrapartum period is relatively short compared to the complete perinatal period, there is emerging evidence that this time frame may be a critical formative phase for the human genome. Given the debates from the National Institutes of Health and World Health Organization regarding routine childbirth procedures, it is essential to establish the state of the science concerning normal intrapartum epigenetic physiology. EPIIC (Epigenetic Impact of Childbirth) is an international, interdisciplinary research collaboration with expertise in the fields of genetics, physiology, developmental biology, epidemiology, medicine, midwifery, and nursing. We hypothesize that events during the intrapartum period - specifically the use of synthetic oxytocin, antibiotics, and cesarean section - affect the epigenetic remodeling processes and subsequent health of the mother and offspring. The rationale for this hypothesis is based on recent evidence and current best practice.
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Cesárea , Epigénesis Genética/genética , Epigenómica/métodos , Enfermedades del Recién Nacido/genética , Trabajo de Parto/genética , Modelos Genéticos , Femenino , Humanos , Recién Nacido , EmbarazoRESUMEN
BACKGROUND: Perineal pain associated with perineal trauma is often underestimated. Offering regular pain relief may be advantageous compared to waiting for women to request it. Changing clinical practice in a sustained way needs a whole of team approach. AIM: To reduce women's pain following perineal trauma in the first 48 h following childbirth and to undertake this as multidisciplinary, quality activity. METHODS: In November 2008 a questionnaire was distributed to 18 new mothers who had sustained perineal trauma during the birth in order to assess pain levels in the first 48 h and to investigate pain management therapies used. Following this survey a multidisciplinary project team undertook a series of brainstorming sessions, reviewed the literature and undertook staff surveys to identify key factors impacting on women's perineal pain. A process of decision making led to education and support of women and staff. An evidence based guideline, which involved prescribing regular pain relief for women and offering an ice pack within 1h of giving birth was implemented, and a brochure was designed for women. A follow up questionnaire was distributed in June 2010 to 18 women and pain scores before and after the change in policy were compared. RESULTS: Prior to the practice change in 2008 67% of the women surveyed rated their pain as 'moderate' to 'a lot' 48 h following the birth. Following the change in practice and implementation of a new guideline a second survey in 2010 at 48 h postpartum found 60% of women in the post intervention group rated their perineal pain as 'a lot' to 'moderate'. There had been a 33% increase in women's use of pain relief options compared to the pre-intervention survey. The practice change was sustained and adopted by all the staff. CONCLUSION: By taking a multidisciplinary quality activity an effective practice change was facilitated that appeared to decrease women's perineal pain in the 48 h following birth.
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Medicina Basada en la Evidencia , Manejo del Dolor/normas , Dolor/etiología , Perineo/lesiones , Guías de Práctica Clínica como Asunto , Trastornos Puerperales/etiología , Adulto , Analgésicos/administración & dosificación , Crioterapia/métodos , Episiotomía/efectos adversos , Femenino , Encuestas de Atención de la Salud , Humanos , Manejo del Dolor/métodos , Periodo Posparto , Embarazo , Trastornos Puerperales/terapia , Encuestas y CuestionariosRESUMEN
In Australia private homebirth remains unfunded and uninsured and publicly funded homebirth models are not widely available. Doulas are increasingly hired by women for support during childbirth and freebirth (birth intentionally unattended by a health professional) appears to be on the rise. The recently released Improving Maternity Services in Australia--The Report of the Maternity Services Review (MSR) exclude homebirth from the funding and insurance reforms proposed. Drawing on recent research we argue that homebirth has become a casualty of a broken maternity system. The recent rise in the numbers of women employing doulas and choosing to birth at home unattended by any health professional, we argue, is in part a consequence of not adequately meeting the needs of women for continuity of midwifery care and non-medicalised birthing options.
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Parto Obstétrico/métodos , Doulas , Necesidades y Demandas de Servicios de Salud , Parto Domiciliario/métodos , Servicios de Salud Materna/economía , Actitud del Personal de Salud , Australia , Conducta de Elección , Continuidad de la Atención al Paciente , Parto Obstétrico/efectos adversos , Femenino , Parto Domiciliario/efectos adversos , Humanos , Bienestar Materno , Partería , Embarazo , Factores de Riesgo , Recursos HumanosRESUMEN
Preparations of isolated porcine gastric cells, enriched in parietal cells, were used to study binding of epidermal growth factor (EGF) to receptors and subsequent inhibition of [14C]aminopyrine uptake. EGF in concentrations from 10(-10) to 10(-7) M inhibited aminopyrine uptake stimulated by 10(-5) M histamine with an IC50 of 3 x 10(-10) M. [125]EGF bound in a saturable and specific manner to sites on cells in preparations containing 40-90% parietal cells. Mean apparent dissociation constant for the sites was 1.6 x 10(-9) M, with an average number of approximately 20,000 sites per cell. Endocytosis of ligand by parietal cells was limited, amounting to 10-20% of bound EGF after 1 h of incubation at 37 degrees C. Occupation of a fraction of the receptors caused a maximal reduction by 40% of aminopyrine uptake in histamine-stimulated cells, suggesting the occurrence of spare receptors. The results indicate the existence of specific receptors for EGF on porcine parietal cells exerting a regulatory influence on acid secretion.
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Aminopirina/farmacocinética , Factor de Crecimiento Epidérmico/metabolismo , Receptores ErbB/metabolismo , Células Parietales Gástricas/metabolismo , Animales , Factor de Crecimiento Epidérmico/farmacología , Histamina/farmacología , Técnicas In Vitro , Radioisótopos de Yodo , PorcinosRESUMEN
1. Cytoplasmic Ca2+ ([Ca2+]i) responses were studied in guinea-pig pancreatic acinar cells during stimulation with cholecystokinin octapeptide (CCK-8), substance P (SP) and carbachol. 2. Individual cells exhibited [Ca2+]i responses to all three agonists. 3. In the absence of external Ca2+, all the agonists initiated [Ca2+]i peaks which, particularly at high agonist concentrations, rapidly declined. 4. SP induced repetitive monophasic [Ca2+]i transients which started from basal [Ca2+]i even after elevation of the external Ca2+ concentration. 5. CCK-8 triggered similar oscillations, which particularly at high agonist concentration or after elevating external Ca2+ became superimposed upon a sustained elevation of [Ca2+]i. 6. Carbachol-induced oscillations were more complex with [Ca2+]i transients superimposed on slower waves. 7. At high carbachol concentrations or elevation of external Ca2+ the slow waves fused into a sustained increase of [Ca2+]i. 8. The protein kinase C (PKC) activator 12-O-tetradecanoylphorbol-13-acetate attenuated the agonist-induced [Ca2+]i responses, and this effect was reversed by the PKC activator staurosporine. 9. The results indicate that oscillations of [Ca2+]i induced by SP, CCK-8 and carbachol involve intracellular mobilization of Ca2+. 10. CCK-8 and carbachol also cause a rise of [Ca2+]i by a mechanism more directly dependent on the presence of extracellular Ca2+. 11. In the case of carbachol the latter component is subject to oscillatory control. 12. The transition from oscillatory [Ca2+]i to sustained increase may be associated with inhibition of amylase release.
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Calcio/metabolismo , Carbacol/farmacología , Colecistoquinina/farmacología , Páncreas/efectos de los fármacos , Sustancia P/farmacología , Animales , Relación Dosis-Respuesta a Droga , Cobayas , Masculino , Páncreas/citología , Páncreas/metabolismoRESUMEN
The kinetics of the changes in the cytoplasmic Ca2+ concentration (Ca2+i) and amylase release were measured in fura-2-loaded pancreatic acinar cells and perifused pancreatic acini, respectively. Cholecystokinin octapeptide (CCK-8) and its amphibian analogue caerulein induced similar dose-related increases of Ca2+i and amylase secretion with threshold concentrations of 2-6 x 10(-12) M, and maximal effects at 2 x 10(-10) M. The action of CCK/caerulein on Ca2+i was complex and similar to that of carbachol and bombesin with a prompt several-fold increase within seconds followed by a gradual decline over more than 5 min to a new sustained suprabasal level. The kinetics of amylase release in response to CCK and carbachol correlated with the changes in Ca2+i. Additions of the antagonists N2,O2-dibutyrylguanosine 3':5'-cyclic monophosphate and atropine after 30 min of CCK-8 and carbachol stimulation, respectively, were associated with prompt lowerings of Ca2+i and inhibitions of amylase secretion. The patterns observed with substance P (SP) and eledoisin were different with high concentrations (10(-8)-10(-7) M) giving monophasic increases of Ca2+i and amylase release. An initial stimulation of cells with a high dose of CCK eliminated the Ca2+i response to further stimulation with CCK, carbachol, bombesin and SP, whereas cells subjected to initial stimulation with SP responded to subsequent exposure to CCK with prolonged elevation of Ca2+i. The data indicate that stimulation with CCK, carbachol and bombesin may be associated with intracellular mobilization of calcium from more than one pool, and that an increase of Ca2+i is involved even in threshold stimulation of amylase release.