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Arafa A, Sheerah HA, Alzaydan OK, Sabr Y. The Association between Antenatal Tea Drinking and Hypertensive Disorders of Pregnancy: A Systematic Review and Meta-Analysis. EPIDEMIOLOGIA 2024; 5:200-210. [PMID: 38804341 PMCID: PMC11130964 DOI: 10.3390/epidemiologia5020014] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2024] [Revised: 04/11/2024] [Accepted: 04/26/2024] [Indexed: 05/29/2024] Open
Abstract
Several adverse maternal outcomes have been linked to the excessive consumption of caffeine during pregnancy. Tea is an important source of caffeine. Hypertensive disorders of pregnancy (HDP) are common pregnancy complications with unfavorable maternal and fetal complications. This study aimed to investigate the relationship between antenatal tea drinking and HDP using a meta-analysis of available evidence. We systematically retrieved eligible studies before computing the pooled odds ratio (OR) and 95% confidence interval (CI) of HDP for women who reported the highest versus the lowest frequencies of antenatal tea drinking. We used the I2 statistic to measure heterogeneity across studies and the test for funnel plot asymmetry to evaluate publication bias. The results showed that the highest frequencies of antenatal tea drinking were associated with increased odds of HDP (pooled OR = 1.16, 95% CI: 1.01, 1.33). We identified no signs of heterogeneity across studies (I2 = 0.0% and p-heterogeneity = 0.498) or publication bias (z = 0.791 and p-publication bias = 0.429). When the outcome was limited to (pre-)eclampsia, the association became statistically non-significant (pooled OR = 1.28, 95% CI: 0.86, 1.89, I2 = 0.0%, and p-heterogeneity = 0.751). In conclusion, our results indicated that the highest frequency of antenatal tea drinking was positively associated with HDP. Pregnant women should be advised against excessive tea consumption. Still, future prospective cohort studies, considering the effects of different tea types and caffeine content, are needed to confirm our conclusions.
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Affiliation(s)
- Ahmed Arafa
- Department of Preventive Cardiology, National Cerebral and Cardiovascular Center, Suita 564-8565, Japan
- Department of Public Health, Faculty of Medicine, Beni-Suef University, Beni-Suef 2721562, Egypt
| | - Haytham A. Sheerah
- Office of the Vice Minister of Health, Ministry of Health, Riyadh 12631, Saudi Arabia;
| | - Omar Khaled Alzaydan
- King Saud University Medical City, King Saud University, Riyadh 12372, Saudi Arabia; (O.K.A.); (Y.S.)
| | - Yasser Sabr
- King Saud University Medical City, King Saud University, Riyadh 12372, Saudi Arabia; (O.K.A.); (Y.S.)
- Department of Obstetrics and Gynecology, College of Medicine, King Saud University, Riyadh 11472, Saudi Arabia
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2
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Kim HJ, Kim SS, Song SH. Glomerular filtration rate as a kidney outcome of diabetic kidney disease: a focus on new antidiabetic drugs. Korean J Intern Med 2022; 37:502-519. [PMID: 35368179 PMCID: PMC9082447 DOI: 10.3904/kjim.2021.515] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/25/2021] [Accepted: 02/17/2022] [Indexed: 11/27/2022] Open
Abstract
Diabetes has reached epidemic proportions, both in Korea and worldwide and is associated with an increased risk of chronic kidney disease and kidney failure (KF). The natural course of kidney function among people with diabetes (especially type 2 diabetes) may be complex in real-world situations. Strong evidence from observational data and clinical trials has demonstrated a consistent association between decreased estimated glomerular filtration rate (eGFR) and subsequent development of hard renal endpoints (such as KF or renal death). The disadvantage of hard renal endpoints is that they require a long follow-up duration. In addition, there are many patients with diabetes whose renal function declines without the appearance of albuminuria, measurement of the eGFR is emphasized. Many studies have used GFR-related parameters, such as its change, decline, or slope, as clinical endpoints for kidney disease progression. In this respect, understanding the trends in GFR changes could be crucial for developing clinical management strategies for the prevention of diabetic complications. This review focuses on the clinical implication of the eGFR-related parameters that have been used so far in diabetic kidney disease. We also discuss the use of recently developed new antidiabetic drugs for kidney protection, with a focus on the GFR as clinical endpoints.
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Affiliation(s)
- Hyo Jin Kim
- Division of Nephrology, Department of Internal Medicine, Pusan National University Hospital, Busan,
Korea
- Biomedical Research Institute, Pusan National University Hospital, Busan,
Korea
| | - Sang Soo Kim
- Biomedical Research Institute, Pusan National University Hospital, Busan,
Korea
- Division of Endocrinology and Metabolism, Department of Internal Medicine, Pusan National University Hospital, Busan,
Korea
| | - Sang Heon Song
- Division of Nephrology, Department of Internal Medicine, Pusan National University Hospital, Busan,
Korea
- Biomedical Research Institute, Pusan National University Hospital, Busan,
Korea
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3
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Villanueva-García D, Mota-Rojas D, Miranda-Cortés A, Ibarra-Ríos D, Casas-Alvarado A, Mora-Medina P, Martínez-Burnes J, Olmos-Hernández A, Hernández-Avalos I. Caffeine: cardiorespiratory effects and tissue protection in animal models. Exp Anim 2021; 70:431-439. [PMID: 34039788 PMCID: PMC8614017 DOI: 10.1538/expanim.20-0185] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2021] [Accepted: 04/20/2021] [Indexed: 10/31/2022] Open
Abstract
The aim of this review is to analyze the cardiorespiratory and tissue-protective effects of caffeine in animal models. Peer-reviewed literature published between 1975 and 2021 was retrieved from CAB Abstracts, PubMed, ISI Web of Knowledge, and Scopus. Extracted data were analyzed to address the mechanism of action of caffeine on cardiorespiratory parameters (heart rate and rhythm), vasopressor effects, and some indices of respiratory function; we close this review by discussing the current debate on the research carried out on the effects of caffeine on tissue protection. Adenosine acts through specific receptors and is a negative inotropic and chronotropic agent. Blockage of its cardiac receptors can cause tachycardia (with arrhythmogenic potential) due to the intense activity of β1 receptors. In terms of tissue protection, caffeine inhibits hyperoxia-induced pulmonary inflammation by decreasing proinflammatory cytokine expression in animal models. The protection that caffeine provides to tissues is not limited to the CNS, as studies have demonstrated that it generates attenuation of inflammatory effects in pulmonary tissue. It inhibits the effects of some pro-inflammatory cytokines and prevents functional and structural changes.
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Affiliation(s)
- Dina Villanueva-García
- Division of Neonatology, National Institute of Health, Hospital Infantil de México Federico Gómez, Doctor Márquez 162, 06720, Mexico City, Mexico
| | - Daniel Mota-Rojas
- Neurophysiology, Behavior, and Animal Welfare Assessment, Department of Animal Production and Agriculture (DPAA), Universidad Autónoma Metropolitana (UAM) Xochimilco Campus, Calzada del Hueso 1100. Col. Villa Quietud. Coyoacán, 04960, Mexico City, Mexico
| | - Agatha Miranda-Cortés
- Clinical Pharmacology and Veterinary Anaesthesia, Department of Biological Science, FESC, Universidad Nacional Autónoma de México (UNAM), Carretera Cuautitlán-Teoloyucan Km. 2.5 San Sebastian Xhala, 54714, Cuautitlán Izcalli, State of Mexico, Mexico
| | - Daniel Ibarra-Ríos
- Division of Neonatology, National Institute of Health, Hospital Infantil de México Federico Gómez, Doctor Márquez 162, 06720, Mexico City, Mexico
| | - Alejandro Casas-Alvarado
- Neurophysiology, Behavior, and Animal Welfare Assessment, Department of Animal Production and Agriculture (DPAA), Universidad Autónoma Metropolitana (UAM) Xochimilco Campus, Calzada del Hueso 1100. Col. Villa Quietud. Coyoacán, 04960, Mexico City, Mexico
| | - Patricia Mora-Medina
- Livestock Science Department, Universidad Nacional Autónoma de México (UNAM), Facultad de Estudios Superiores Cuautitlán, Carretera Cuautitlán-Teoloyucan Km. 2.5 San Sabastian Xhala, 54714, Cuautitlán Izcalli, State of Mexico, Mexico
| | - Julio Martínez-Burnes
- Graduate and Research Department, Facultad de Medicina Veterinaria y Zootecnia, Universidad Autónoma de Tamaulipas, Km 5 Carretera Victoria-Mante, 87000, Cd. Victoria, Tamaulipas, Mexico
| | - Adriana Olmos-Hernández
- Division of Biotechnology, Department Bioterio and Experimental Surgery. Instituto Nacional de Rehabilitación-Luis Guillermo Ibarra Ibarra (INR-LGII), Calzada México Xochimilco, 289, 14389, Mexico City, Mexico
| | - Ismael Hernández-Avalos
- Clinical Pharmacology and Veterinary Anaesthesia, Department of Biological Science, FESC, Universidad Nacional Autónoma de México (UNAM), Carretera Cuautitlán-Teoloyucan Km. 2.5 San Sebastian Xhala, 54714, Cuautitlán Izcalli, State of Mexico, Mexico
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4
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Sicova M, Guest NS, Tyrrell PN, El-Sohemy A. Caffeine, genetic variation and anaerobic performance in male athletes: a randomized controlled trial. Eur J Appl Physiol 2021; 121:3499-3513. [PMID: 34529114 DOI: 10.1007/s00421-021-04799-x] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2021] [Accepted: 08/18/2021] [Indexed: 11/26/2022]
Abstract
PURPOSE The effect of caffeine on anaerobic performance is unclear and may differ depending on an individual's genetics. The goal of this study was to determine whether caffeine influences anaerobic performance in a 30 s Wingate test, and if 14 single nucleotide polymorphisms (SNPs) in nine genes, associated with caffeine metabolism or response, modify caffeine's effects. METHODS Competitive male athletes (N = 100; 25 ± 4 years) completed the Wingate under three conditions: 0, 2, or 4 mg of caffeine per kg of body mass (mg kg-1), using a double-blinded, placebo-controlled design. Using saliva samples, participants were genotyped for the 14 SNPs. The outcomes were peak power (Watts [W]), average power (Watts [W]), and fatigue index (%). RESULTS There was no main effect of caffeine on Wingate outcomes. One significant caffeine-gene interaction was observed for CYP1A2 (rs762551, p = 0.004) on average power. However, post hoc analysis showed no difference in caffeine's effects within CYP1A2 genotypes for average power performance. No significant caffeine-gene interactions were observed for the remaining SNPs on peak power, average power and fatigue index. CONCLUSION Caffeine had no effect on anaerobic performance and variations in several genes did not modify any effects of caffeine. TRIAL REGISTRATION This study was registered with clinicaltrials.gov (NCT02109783).
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Affiliation(s)
- Marc Sicova
- Temerty Faculty of Medicine, Department of Nutritional Sciences, University of Toronto, 1 King's College Circle, Room 5326A, Toronto, ON, M5S 1A8, Canada
| | - Nanci S Guest
- Temerty Faculty of Medicine, Department of Nutritional Sciences, University of Toronto, 1 King's College Circle, Room 5326A, Toronto, ON, M5S 1A8, Canada
| | - Pascal N Tyrrell
- Faculty of Arts and Science, Department of Statistical Sciences, University of Toronto, Toronto, ON, Canada
- Temerty Faculty of Medicine, Institute of Medical Sciences, Department of Medical Imaging, University of Toronto, Toronto, ON, Canada
| | - Ahmed El-Sohemy
- Temerty Faculty of Medicine, Department of Nutritional Sciences, University of Toronto, 1 King's College Circle, Room 5326A, Toronto, ON, M5S 1A8, Canada.
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5
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Rorabaugh BR. Does Prenatal Exposure to CNS Stimulants Increase the Risk of Cardiovascular Disease in Adult Offspring? Front Cardiovasc Med 2021; 8:652634. [PMID: 33748200 PMCID: PMC7969998 DOI: 10.3389/fcvm.2021.652634] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2021] [Accepted: 02/15/2021] [Indexed: 12/11/2022] Open
Abstract
Prenatal exposure to an adverse uterine environment can have long lasting effects on adult offspring through DNA methylation, histone acetylation, and other epigenetic effects that alter gene expression and physiology. It is well-known that consumption of CNS stimulants such as caffeine, nicotine, amphetamines, and cocaine during pregnancy can adversely impact the offspring. However, most work in this area has focused on neurological and behavioral outcomes and has been limited to assessments in young offspring. The impact of prenatal exposure to these agents on the adult cardiovascular system has received relatively little attention. Evidence from both animal and human studies indicate that exposure to CNS stimulants during the gestational period can negatively impact the adult heart and vasculature, potentially leading to cardiovascular diseases later in life. This review discusses our current understanding of the impact of prenatal exposure to cocaine, methamphetamine, nicotine, and caffeine on the adult cardiovascular system.
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Affiliation(s)
- Boyd R Rorabaugh
- Department of Pharmaceutical Science, Marshall University School of Pharmacy, Huntington, WV, United States
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6
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Caffeine effects on systemic metabolism, oxidative-inflammatory pathways, and exercise performance. Nutr Res 2020; 80:1-17. [DOI: 10.1016/j.nutres.2020.05.005] [Citation(s) in RCA: 27] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2019] [Revised: 04/11/2020] [Accepted: 05/09/2020] [Indexed: 01/06/2023]
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7
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Adipose tissue of female Wistar rats respond to Ilex paraguariensis treatment after ovariectomy surgery. J Tradit Complement Med 2020; 11:238-248. [PMID: 34012870 PMCID: PMC8116720 DOI: 10.1016/j.jtcme.2020.07.002] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2020] [Revised: 07/15/2020] [Accepted: 07/16/2020] [Indexed: 12/13/2022] Open
Abstract
Background and aim Metabolic disturbances are known for their increasing epidemiological importance. Ilex paraguariensis presents a potential option for mitigating lipid metabolism imbalance. However, most of the literature to date has not considered sex bias. This study aimed to evaluate the effect of Ilex paraguariensis on the metabolism of different adipose tissue depots in males and females. Experimental procedure After ovariectomy, female Wistar rats received daily treatment with the extract (1 g/kg) for forty-five days. Biochemical serum parameters and tissue metabolism were evaluated. Oxidation, lipogenesis and lipolysis were evaluated in brown, white visceral, retroperitoneal and gonadal adipose tissues. Results and conclusion The results showed that treatment with the extract led to a reduced weight gain in ovariectomised females in comparison to control. The triglyceride concentration was decreased in males. Glucose oxidation and lipid synthesis in visceral and retroperitoneal adipose tissues were restored in ovariectomised females after treatment. The response to epinephrine decreased in visceral adipose tissue of control males; however, lipolysis in females did not respond to ovariectomy or treatment. These findings highlight the enormous potential effects of I. paraguariensis on lipid metabolism, modulating lipogenic pathways in females and lipolytic pathways in males. Furthermore, the sex approach applied in this study contributes to more effective screening of the effects of I. paraguariensis bioactive substances. Ilex paraguariensis reduced weight gain of ovariectomy females to control levels Serum triglycerides decreased in male and estrogen-deficient female after treatment Treatment restored glucose oxidation and lipogenesis of estrogen-deficient females I. paraguariensis decreased lipolysis response in visceral adipose tissue of males
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8
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Effect of yerba mate (Ilex paraguariensis) extract on the metabolism of diabetic rats. Biomed Pharmacother 2018; 105:370-376. [PMID: 29864625 DOI: 10.1016/j.biopha.2018.05.132] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2018] [Revised: 05/28/2018] [Accepted: 05/28/2018] [Indexed: 01/11/2023] Open
Abstract
The relationship between metabolic disturbances and clinical events related to diabetes is well known. Yerba mate has presented a potential use as preventive and therapeutic agent on diabetes. The aim of this study was to evaluate the effect of yerba mate on different tissues of diabetic rats, focusing on energetic metabolism. Diabetes was induced by streptozotocin, followed by daily yerba mate treatment. After 30 days, the animals were euthanized to evaluate metabolic parameters on liver, adipose tissue, muscle and serum. The results showed mate treatment promoted a decrease in retroperitoneal adipose tissue in healthy animals. Muscle weight returned to control levels in diabetic rats treated with mate. There was improvement on serum glucose, creatinine, urea and total protein levels associated with mate treatment. Muscle parameters, such as glucose uptake and carbon dioxide production, were improved by mate treatment to control levels. The results evidenced the beneficial actions mate can have on metabolic disturbances of diabetes.
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9
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Zacher J, May E, Horlitz M, Pingel S. Binge drinking alcohol with caffeinated "energy drinks", prolonged emesis and spontaneous coronary artery dissection: a case report, review of the literature and postulation of a pathomechanism. Clin Res Cardiol 2018; 107:975-979. [PMID: 29728830 DOI: 10.1007/s00392-018-1262-y] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/21/2018] [Accepted: 04/24/2018] [Indexed: 11/24/2022]
Affiliation(s)
- Jonas Zacher
- Department of Cardiology, Electrophysiology and Rhythmology, Krankenhaus Porz am Rhein, Urbacher Weg 19, 51149, Cologne, Germany.
| | - Erik May
- Department of Cardiology, Electrophysiology and Rhythmology, Krankenhaus Porz am Rhein, Urbacher Weg 19, 51149, Cologne, Germany
| | - Marc Horlitz
- Department of Cardiology, Electrophysiology and Rhythmology, Krankenhaus Porz am Rhein, Urbacher Weg 19, 51149, Cologne, Germany.,University of Witten/Herdecke, Alfred-Herrhausen-Straße 50, 58448, Witten, Germany
| | - Simon Pingel
- Department of Cardiology, Electrophysiology and Rhythmology, Krankenhaus Porz am Rhein, Urbacher Weg 19, 51149, Cologne, Germany
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10
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Ruiz R, Ramos SDP, Pinge MM, Moraes SFD, Polito M. Caffeine and physical training: effects on cardiac morphology and cardiovascular response. Rev Assoc Med Bras (1992) 2014; 60:23-8. [DOI: 10.1590/1806-9282.60.01.007] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2013] [Accepted: 08/05/2013] [Indexed: 11/22/2022] Open
Abstract
Objective to analyze the morphological structure of cardiac, blood pressure (BP), heart rate (HR) and heart rate variability (HRV) of rats subjected to physical training with supplementation of caffeine. Methods 60 rats were divided into 4 groups: control (CO), control with caffeine (CAF), trained control (TRE) and trained with caffeine (TCAF). All trained groups underwent 4 weeks of swimming, and all caffeine groups were supplemented by voluntary ingestion of caffeine diluted in drinking water. Results there were no changes to BP and HR between groups. Regarding HRV, there was a decrease in LFnorm (low frequency) and LF/HF ratio (low and high frequency) in TCAF and CAF compared to group (p<0.02 and p<0.03, respectively). An increase occurred in CAF compared to the CO in the component LFnorm (p<0.05). The results also showed an increase in the relative weight of heart in the TRE (p<0.04) and TCAF (p<0.03) compared to CO. Conclusion caffeine did not modify the hemodynamic responses. However, physical training resulted in a decrease in sympathetic response and an increase in relative heart weight.
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11
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Das T, Yoo YS, Rhim H, Song EJ. Potential role of Hsp25 in calcium-modulated cardiomyocytes. Proteomics 2012; 12:411-20. [DOI: 10.1002/pmic.201100151] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2011] [Revised: 10/26/2011] [Accepted: 11/14/2011] [Indexed: 11/10/2022]
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Ziogas J, O'Farrell M. Studies on the mechanism of enhancement of purinergic transmission by caffeine in the guinea-pig isolated vas deferens. AUTONOMIC & AUTACOID PHARMACOLOGY 2002; 22:161-9. [PMID: 12452901 DOI: 10.1046/j.1474-8673.2002.00256.x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/19/2023]
Abstract
1. Purinergic transmission from sympathetic nerves in the guinea-pig vas deferens was monitored using intracellular recording techniques. Stimulation of the hypogastric nerve with trains of 15 pulses at 1 Hz evoked excitatory junction potentials (EJPs) which increased in amplitude from the first pulse and reached a maximum after 6-8 pulses. 2. Caffeine (3 and 10 mm), depolarized cells by 5-10 mV and increased the amplitude of the first few EJPs in each train but reduced the maximum amplitude of EJPs late in the train. 3. The adenosine receptor antagonist 8-p-sulphophenyl-theophylline (8-SPT; 30 microm) had no effect on either the resting membrane potential or the EJP amplitude; however, at 100 microm it reduced the amplitude of all EJPs by 5-10%. 4. Adenosine (10 and 30 microm) reduced the amplitude of EJPs in a concentration-dependent manner. The inhibitory effect of adenosine on EJP amplitude was prevented by pretreatment with either caffeine (3 mm) or 8-SPT (30 microm). 5. Ryanodine (30 microm) did not alter EJP amplitude and did not inhibit the enhancement of the first EJP by caffeine (3 mm). Incubation of the tissue with the cell permeable calcium chelator 1-2-bis(o-aminophenoxy)ethane-N,N-N',N'-tetraacetic acid (BAPT-AM) resulted in a depression of EJP amplitude and a longer time to reach maximum amplitude. In cells that had been exposed to BAPT-AM, caffeine 3 mm still increased amplitude of EJP early in the train. 6. The phosphodiesterase inhibitor, 3-isobutyl-1-methylxanthine (IBMX; 500 microm), hyperpolarized cells and increased the amplitude of EJP throughout the train of stimulation. In the presence of IBMX, caffeine 3 mm still depolarized the cells and enhanced the EJP early in the train of stimulation. 7. The findings in this study confirm that caffeine and 8-SPT are effective inhibitors of the actions of adenosine. However, caffeine has an additional action to enhance EJP early during a train of stimulation, which cannot be attributed to blockade of adenosine receptors, but which may be related to inhibition of phosphodiesterase.
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Affiliation(s)
- J Ziogas
- Department of Pharmacology, University of Melbourne, Victoria 3010, Australia
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Vicario I, Obeso A, Rocher A, López-Lopez JR, González C. Intracellular Ca(2+) stores in chemoreceptor cells of the rabbit carotid body: significance for chemoreception. Am J Physiol Cell Physiol 2000; 279:C51-61. [PMID: 10898716 DOI: 10.1152/ajpcell.2000.279.1.c51] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The notion that intracellular Ca(2+) (Ca(i)(2+)) stores play a significant role in the chemoreception process in chemoreceptor cells of the carotid body (CB) appears in the literature in a recurrent manner. However, the structural identity of the Ca(2+) stores and their real significance in the function of chemoreceptor cells are unknown. To assess the functional significance of Ca(i)(2+) stores in chemoreceptor cells, we have monitored 1) the release of catecholamines (CA) from the cells using an in vitro preparation of intact rabbit CB and 2) the intracellular Ca(2+) concentration ([Ca(2+)](i)) using isolated chemoreceptor cells; both parameters were measured in the absence or the presence of agents interfering with the storage of Ca(2+). We found that threshold [Ca(2+)](i) for high extracellular K(+) (K(e)(+)) to elicit a release response is approximately 250 nM. Caffeine (10-40 mM), ryanodine (0.5 microM), thapsigargin (0.05-1 microM), and cyclopiazonic acid (10 microM) did not alter the basal or the stimulus (hypoxia, high K(e)(+))-induced release of CA. The same agents produced Ca(i)(2+) transients of amplitude below secretory threshold; ryanodine (0.5 microM), thapsigargin (1 microM), and cyclopiazonic acid (10 microM) did not alter the magnitude or time course of the Ca(i)(2+) responses elicited by high K(e)(+). Several potential activators of the phospholipase C system (bethanechol, ATP, and bradykinin), and thereby of inositol 1,4,5-trisphosphate receptors, produced minimal or no changes in [Ca(2+)](i) and did not affect the basal release of CA. It is concluded that, in the rabbit CB chemoreceptor cells, Ca(i)(2+) stores do not play a significant role in the instant-to-instant chemoreception process.
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Affiliation(s)
- I Vicario
- Departamento de Bioquímica y Biología Molecular y Fisiología, Instituto de Biología y Genética Molecular and Facultad de Medicina, Universidad de Valladolid, 47005 Valladolid, Spain
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14
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Teraoka H, Akiba H, Takai R, Taneike T, Hiraga T, Ohga A. Inhibitory effects of caffeine on Ca2+ influx and histamine secretion independent of cAMP in rat peritoneal mast cells. GENERAL PHARMACOLOGY 1997; 28:237-43. [PMID: 9013201 DOI: 10.1016/s0306-3623(96)00186-3] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
1. Caffeine did not evoke Ca2+ mobilization and histamine secretion. 2. Caffeine, as well as other methylxanthines but not forskolin or 8 bromo-cAMP, inhibited Ca2+ responses from compound 48/80. 3. Evoked histamine secretion was severely reduced by caffeine but not by cAMP analogs. 4. In beta-escin-permeabilized cells, caffeine did not affect resting and IP3-stimulated 45Ca2+ release, but it inhibited Ca(2+)-induced histamine secretion. 5. These results indicate that caffeine inhibits Ca2+ influx and Ca2+ efficacy in the secretory apparatus independent of cAMP, resulting in the inhibition of secretagogs-evoked histamine secretion from rat mast cells.
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Affiliation(s)
- H Teraoka
- Department of Toxicology, School of Veterinary Medicine, Rakuno Gakuen University, Ebetsu, Japan
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15
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Ohta T, Asano T, Ito S, Kitamura N, Nakazato Y. Characteristics of cytosolic Ca2+ elevation induced by muscarinic receptor activation in single adrenal chromaffin cells of the guinea pig. Cell Calcium 1996; 20:303-14. [PMID: 8894277 DOI: 10.1016/s0143-4160(96)90036-6] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
In Fura-2 loaded-single guinea pig adrenal chromaffin cells, muscarine, nicotine and KCl all caused an early peak rise in intracellular Ca concentration ([Ca2+]i) followed by a sustained rise. In Ca(2+)-free solution, muscarine, but neither nicotine nor KCl, caused a transient increase in [Ca2+]i, which was partially reduced by preceding application of caffeine or by treatment with ryanodine plus caffeine. In voltage-clamped cells at a holding potential of -60 mV, the muscarine-induced [Ca2+]i rise, especially its sustained phase, decreased in magnitude. Intracellular application of inositol 1,4,5-trisphosphate caused a transient increase in [Ca2+]i and inhibited the following [Ca2+]i response to muscarine without affecting responses to nicotine and a depolarizing pulse. Muscarine evoked membrane depolarization following brief hyperpolarization in most cells tested. There was a significant positive correlation between the amplitude of the depolarization and the magnitude of the sustained rise in [Ca2+]i. Muscarine-induced sustained [Ca2+]i rise was much greater in the current-clamp mode than that in the voltage-clamp mode. The sustained phase of [Ca2+]i rise and Mn2+ influx in response to muscarine were suppressed by a voltage-dependent Ca2+ channel blocker, methoxyverapamil. These results suggest that stimulation of muscarinic receptors causes not only extracellular Ca2+ entry, but also Ca2+ mobilization from inositol 1,4,5-trisphosphate-sensitive intracellular stores. Voltage-dependent Ca(2+)-channels may function as one of the Ca2+ entry pathways activated by muscarinic receptor in guinea pig adrenal chromaffin cells.
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Affiliation(s)
- T Ohta
- Laboratory of Pharmacology, Graduate School of Veterinary Medicine, Hokkaido University, Sapporo, Japan.
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16
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Ziogas J, O'Farrell M, Slaughter M. Caffeine enhances sympathetic purinergic and noradrenergic transmission in the guinea-pig isolated vas deferens. NAUNYN-SCHMIEDEBERG'S ARCHIVES OF PHARMACOLOGY 1995; 352:497-505. [PMID: 8751078 DOI: 10.1007/bf00169383] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
Intracellular recording techniques were used to monitor the resting membrane potential of smooth muscle cells and the excitatory junction potentials (EJPs) evoked by stimulation of the hypogastric nerve. Stimulation with trains of 15 pulses at 1 Hz or 0.33 Hz evoked individual EJPs which increased in amplitude from the first pulse and reached a plateau after 6-8 pulses. Stimulation at 1 Hz resulted in EJPs facilitating to a plateau level of approximately 25 mV, whereas with stimulation at 0.33 Hz the EJPs only facilitated to a plateau level of about 12 mV. With stimulation at 1 Hz, caffeine (3 mM and 10 mM), increased the amplitude of the first few EJPs in each train and decreased the extent of facilitation and reduced the amplitude of fully facilitated EJPs. In comparison, the amplitude of all EJPs evoked by stimulation at 0.33 Hz was increased by caffeine (3 mM and 10 mM). With 0.33 Hz stimulation, facilitation of the first few EJPs was observed in the presence of 3 mM caffeine but not in the presence of 10 mM caffeine. In the presence of the alpha 2-adrenoceptor antagonist idazoxan, caffeine (3 mM and 10 mM) still enhanced the amplitude of EJPs early in trains of stimulation but there was no depression of EJPs later in the trains. Similarly, in reserpine-treated vasa deferentia, caffeine (3 mM) enhanced EJPs early in the train of stimulation at 1 Hz and there was no depression of EJPs at the end of the train. In addition to electrophysiological experiments, the effect of caffeine (0.1-30 mM) on the resting and stimulation-induced (S-I) efflux of radioactivity was investigated in guinea-pig isolated vasa deferentia previously incubated with [3H]-noradrenaline. Caffeine (10 mM) did not affect the resting efflux of [3H]-noradrenaline but significantly enhanced the S-I efflux by 150-160%. The present findings suggest that caffeine enhances sympathetic purinergic and noradrenergic transmission at the sympathetic neuroeffector junction in the guinea-pig vas deferens. Moreover, the increased release of transmitter noradrenaline can modulate purinergic transmission by activation of alpha 2-adrenoceptors located at sympathetic neuroeffector sites.
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Affiliation(s)
- J Ziogas
- Department of Pharmacology, University of Melbourne, Parkville Victoria, Australia
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17
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Graham TE, Rush JW, van Soeren MH. Caffeine and exercise: metabolism and performance. CANADIAN JOURNAL OF APPLIED PHYSIOLOGY = REVUE CANADIENNE DE PHYSIOLOGIE APPLIQUEE 1994; 19:111-38. [PMID: 8081318 DOI: 10.1139/h94-010] [Citation(s) in RCA: 65] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
Caffeine ingestion prior to prolonged exercise delays fatigue. However, the mechanisms involved are very unclear. Caffeine is associated with elevated plasma epinephrine but the metabolic impact of this is uncertain. Glycogen sparing occurs in active muscle, at least in the first few minutes, but studies have generally failed to demonstrate enhanced fat metabolism. The demethylation of caffeine by the hepatic cytochrome P-450 oxygenases begins within minutes and dimethylxanthines (especially paraxanthine) are generated. These compounds appear in the plasma within an hour of caffeine ingestion and may have effects on tissues that have been attributed to caffeine and/or epinephrine. While the most widely supported theory is that caffeine and other methylxanthines are adenosine receptor antagonists, this action alone cannot explain all of the observed responses. Nevertheless, habituation to and withdrawal from caffeine are associated with up and down regulation of adenosine receptors. One study demonstrated marked differences in the effects of caffeine on the plasma concentrations of epinephrine and dimethylxanthines between caffeine users and nonusers. Caffeine is clearly a very active drug that has many effects on humans including increasing exercise endurance. This can be associated with muscle glycogen sparing and elevated plasma epinephrine, but the underlying mechanisms are unknown.
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Affiliation(s)
- T E Graham
- School of Human Biology, University of Guelph, Ontario
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18
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Nakazato Y, Tani Y, Teraoka H, Sugawara T, Asano T, Ohta T, Ito S. Inhibitory effects of caffeine on secretagogue-induced catecholamine secretion from adrenal chromaffin cells of the guinea-pig. Br J Pharmacol 1994; 111:935-41. [PMID: 8019771 PMCID: PMC1910062 DOI: 10.1111/j.1476-5381.1994.tb14829.x] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023] Open
Abstract
1. The inhibitory action of caffeine on catecholamine secretion induced by secretagogues was investigated in perfused adrenal glands and dispersed chromaffin cells of the guinea-pig. 2. Caffeine (10 mM) caused a reversible inhibition of catecholamine secretion evoked by acetylcholine (ACh, 50 microM), KCl (56 mM, high K+) and veratridine (100 microM) and that induced by muscarinic receptor activation in the absence of extracellular Ca2+ in perfused adrenal glands. 3. In dispersed chromaffin cells, caffeine caused a dose-dependent inhibition of the secretory responses to 100 microM ACh and veratridine. Forskolin (30 microM), dibutyryl cyclic AMP (1 mM) and 8-bromo cyclic AMP (1 mM) did not mimic the action of caffeine. 4. In the voltage-clamp, whole-cell recording mode (at a holding potential of -60 mV or -70 mV), ACh (100 microM) evoked an inward current, and depolarizing pulses elicited inward Na+, Ca2+ and outward K+ currents. All these responses were partially inhibited by caffeine (20 mM). 5. ACh rapidly increased the intracellular concentration of Ca2+ ([Ca2+]i) in fura-2-loaded cells in either the presence or the absence of external Ca2+, though its magnitude was decreased by about 50% in Ca(2+)-free conditions. Caffeine (20 mM) inhibited these ACh-induced increases in [Ca2+]i. 6. In permeabilized chromaffin cells, caffeine (20 mM) caused an inhibition of catecholamine secretion evoked by Ca2+ (10 microM). 7. These results suggest that caffeine inhibits evoked catecholamine secretion through mechanisms such as the blockade of voltage-dependent Na+ and Ca2+ currents and ACh receptor current, and reduction of the release of intracellularly stored Ca2+ and/or Ca(2+)-sensitivity of the secretory apparatus.
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Affiliation(s)
- Y Nakazato
- Department of Pharmacology, Faculty of Veterinary Medicine, Hokkaido University, Sapporo, Japan
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19
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Sorimachi M, Yamagami K, Nishimura S, Kuramoto K. Possible regulation of caffeine-induced intracellular Ca2+ mobilization by intracellular free Na+. J Neurochem 1992; 59:2271-7. [PMID: 1431907 DOI: 10.1111/j.1471-4159.1992.tb10120.x] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
To gain some understanding of the regulatory mechanism involved in caffeine-induced Ca2+ release in adrenal chromaffin cells, we took advantage of the paradoxical observation that removal of divalent cations potentiated the secretory response to caffeine. We measured the concentration of cytosolic free Ca2+ ([Ca]in) in isolated cat chromaffin cells, by fura-2 microfluorometry, to see whether there was any correlation between the secretory response and the rise in [Ca]in. The caffeine-induced [Ca]in rise and catecholamine secretion were increased by treatment of cells with a divalent cation-deficient solution. These potentiated responses were strongly inhibited either by pretreatment with ryanodine, by the reduction of the external Na+ concentration, or by the addition of Ca2+ channel blockers. Removal of divalent cations caused a large rise in the cytosolic free Na+ concentration ([Na]in), which was measured using SBFI microfluorometry. This rise in [Na]in was reduced either by adding Ca2+ channel blockers or by reducing the external Na+ concentration. These results show a good correlation between caffeine-induced Ca2+ release and [Na]in at the time of stimulation, suggesting that caffeine-induced Ca2+ release is regulated by [Na]in.
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Affiliation(s)
- M Sorimachi
- Department of Physiology, Kagoshima University, School of Medicine, Japan
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20
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Nakazato Y, Hayashi H, Teraoka H. Comparisons of the effects of ryanodine on catecholamine secretion evoked by caffeine and acetylcholine in perfused adrenal glands of the guinea-pig. Br J Pharmacol 1992; 105:597-602. [PMID: 1628147 PMCID: PMC1908453 DOI: 10.1111/j.1476-5381.1992.tb09025.x] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
1. The effect of ryanodine on catecholamine secretion induced by caffeine and muscarinic receptor activation was investigated in perfused adrenal glands of the guinea-pig. 2. Caffeine (40 mM) caused only a small increase in catecholamine secretion during perfusion with standard Locke solution. Caffeine-induced catecholamine secretion was markedly enhanced after removal of CaCl2 together with replacement of NaCl with sucrose. 3. In the absence of CaCl2 and NaCl, 50 microM ryanodine had no effect on the resting catecholamine secretion. Caffeine (40 mM) administered 15 min after treatment with ryanodine caused an increase in catecholamine secretion similar to that prior to application of ryanodine, but failed to have any effect thereafter. Combined application of ryanodine and caffeine also prevented catecholamine secretion induced by caffeine applied subsequently. 4. Catecholamine secretion induced by 100 microM acetylcholine (ACh) was only partially inhibited after treatment with ryanodine plus caffeine under Ca(2+)-free, Na(+)-deficient conditions. 5. Preferential influence of ryanodine on the response to caffeine was also confirmed in catecholamine secretion evoked by paired stimuli with caffeine and ACh alternately, during perfusion with either Ca(2+)-free Locke or sucrose-substituted solutions. 6. These results indicate that caffeine increases catecholamine secretion by mobilizing Ca2+ from intracellular Ca2+ stores through ryanodine-sensitive mechanisms in guinea-pig adrenal chromaffin cells. Ca2+ stores sensitive to caffeine and muscarinic receptor activation may not overlap entirely.
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Affiliation(s)
- Y Nakazato
- Department of Pharmacology, Faculty of Veterinary Medicine, Hokkaido University, Sapporo, Japan
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21
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Collomp K, Ahmaidi S, Chatard JC, Audran M, Préfaut C. Benefits of caffeine ingestion on sprint performance in trained and untrained swimmers. EUROPEAN JOURNAL OF APPLIED PHYSIOLOGY AND OCCUPATIONAL PHYSIOLOGY 1992; 64:377-80. [PMID: 1592065 DOI: 10.1007/bf00636227] [Citation(s) in RCA: 128] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
The influence of specific training on benefits from caffeine (Caf) ingestion was examined during a sprint test in a group of highly trained swimmers (T) and compared with the response of a group of untrained occasional swimmers (UT). Seven T and seven UT subjects swam freestyle two randomly assigned 2 x 100 m distances, at maximal speed and separated by 20 min of passive recovery, once after Caf (250 mg) and once after placebo (Pla) ingestion. Anaerobic capacity was assessed by the mean velocity (meters per second) during each 100 m and blood was sampled from the fingertip just before and 1, 3, 5, 7, and 9 min after each 100 m for resting and maximal blood lactate concentration ([la-]b,max) determination. The [la-]bmax was significantly enhanced by Caf in both T and UT subjects (P less than 0.01). However, only T subjects exhibited significant improvement in their swimming velocity (P less than 0.01) after Caf or any significant impairment during the second 100 m. In light of these results, it appears that specific training is necessary to benefit from the metabolic adaptations induced by Caf during supramaximal exercise requiring a high anaerobic capacity.
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Affiliation(s)
- K Collomp
- Service d'Exploration Fonctionnelle Respiratoire, Hôpital Aiguelongue, Montpellier, France
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22
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Teraoka H, Nakazato Y, Ohga A. Ryanodine inhibits caffeine-evoked Ca2+ mobilization and catecholamine secretion from cultured bovine adrenal chromaffin cells. J Neurochem 1991; 57:1884-90. [PMID: 1940904 DOI: 10.1111/j.1471-4159.1991.tb06399.x] [Citation(s) in RCA: 27] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
The effects of ryanodine, a selective inhibitor of the Ca(2+)-induced Ca2+ release mechanism, on caffeine-evoked changes in cytosolic Ca2+ concentration ([Ca2+]i) and catecholamine secretion were investigated using cultured bovine adrenal chromaffin cells. Caffeine (5-40 mM) caused a concentration-dependent transient rise in [Ca2+]i and catecholamine secretion in Ca2+/Mg(2+)-free medium containing 0.2 mM EGTA. Ryanodine (5 x 10(-5) M) alone had no effect on either [Ca2+]i or catecholamine secretion. Although the application of ryanodine plus caffeine caused the same increase in both [Ca2+]i and catecholamine secretion as those induced by caffeine alone, ryanodine (4 x 10(-7) - 5 x 10(-5) M) irreversibly prevented the increase in both [Ca2+]i and catecholamine secretion resulting from subsequent caffeine application over a range of concentrations. The secretory response to caffeine was markedly enhanced by replacement of Na+ with sucrose in Ca2+/Mg(2+)-free medium, and this enhanced response was also blocked by ryanodine. Caffeine was found to decrease the susceptibility of the secretory apparatus to Ca2+ in digitonin-permeabilized cells. These results indicate that caffeine mobilizes Ca2+ from intracellular stores, the function of which is irreversibly blocked by ryanodine, resulting in the increase in catecholamine secretion in the bovine adrenal chromaffin cell.
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Affiliation(s)
- H Teraoka
- Department of Pharmacology, Faculty of Veterinary Medicine, Hokkaido University, Sapporo, Japan
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23
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Stauderman KA, McKinney RA, Murawsky MM. The role of caffeine-sensitive Ca2+ stores in agonist- and inositol 1,4,5-trisphosphate-induced Ca2+ release from bovine adrenal chromaffin cells. Biochem J 1991; 278 ( Pt 3):643-50. [PMID: 1898353 PMCID: PMC1151395 DOI: 10.1042/bj2780643] [Citation(s) in RCA: 58] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
In single bovine adrenal chromaffin cells loaded with fura-2, histamine, angiotensin II (AII) and caffeine elicited large transient increases of intracellular free Ca2+ concentration [( Ca2+]i) in the absence of external Ca2+, with peak amplitudes averaging 726 +/- 138 (n = 14), 710 +/- 102 (n = 21) and 830 +/- 100 nM (n = 30) respectively. A substantial portion of the agonist-induced rise in [Ca2+]i depended on Ca2+ release from caffeine-sensitive stores, as pretreatment with caffeine diminished subsequent agonist responses by 90-95%. Conversely, pretreatment with histamine or AII decreased subsequent caffeine responses by 100% and 90% respectively. The effects of caffeine most likely resulted from activation of a Ca(2+)-induced Ca(2+)-release (CICR) process, whereas histamine and AII initially acted through generation of Ins(1,4,5)P3. The relationship of Ins(1,4,5)P3- and caffeine-sensitive Ca2+ pools was studied by using alpha-toxin-permeabilized chromaffin cells. Evidence was found for three non-mitochondrial, ATP-dependent, Ca2+ pools: one exclusively sensitive to Ins(1,4,5)P3 (pool 1), a second sensitive to both Ins(1,4,5)P3 and caffeine (pool 2), and a third exclusively sensitive to caffeine (pool 3). The existence of pools 1 and 3, and the ability of agonists such as histamine to discharge pool 3 completely, supports a two-pool model in which a caffeine-sensitive CICR mechanism plays a major role in the generation of agonist-induced Ca2+ spikes in bovine chromaffin cells.
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Affiliation(s)
- K A Stauderman
- Marion Merrell Dow Research Institute, Cincinnati, OH 45215
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24
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Tóth PT, Török TL, Magyar K. Depolarization promotes caffeine induced [3H]-noradrenaline release in calcium-free solution from peripheral sympathetic nerves. Cell Calcium 1990; 11:557-63. [PMID: 2126748 DOI: 10.1016/0143-4160(90)90009-j] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
The transmitter releasing action of caffeine was studied in the absence of extracellular Ca2+ from the peripheral sympathetic nerves of the rabbit main pulmonary artery. Caffeine (10 mM) increased the release of [3H]-noradrenaline moderately, but not significantly in Ca2(+)-free (+1 mM EGTA) Krebs solution. When peripheral nerve endings/varicosities were depolarized by elevating extracellular K+ to 47.2 mM and 70.8 mM in Ca2(+)-free solution, the transmitter releasing effect of 10 mM caffeine became significant. Ca2+ removal itself transiently increased the [3H]-noradrenaline outflow. In the individual experiments the amount of the caffeine evoked transmitter release at 47.2 mM and 70.8 mM K(+)-depolarization was inversely correlated to the release evoked by Ca2(+)-removal. Our results suggest that caffeine-sensitive calcium stores are present in peripheral nerve terminals of rabbit pulmonary artery, and part of the caffeine sensitive calcium stores may discharge during Ca2(+)-removal from the extracellular solution.
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Affiliation(s)
- P T Tóth
- Department of Pharmacodynamics, Semmelweis University of Medicine, Budapest, Hungary
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25
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Teraoka H, Yamada Y, Nakazato Y, Ohga A. The role of Na+ in muscarinic receptor-mediated catecholamine secretion in the absence of extracellular Ca2+ in cat perfused adrenal glands. Br J Pharmacol 1990; 101:67-72. [PMID: 2282468 PMCID: PMC1917635 DOI: 10.1111/j.1476-5381.1990.tb12090.x] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
1. The role of Na+ in muscarinic receptor-mediated catecholamine secretion, which is independent of extracellular Ca2+, was investigated by observing the effect of veratridine and ouabain in perfused adrenal glands of the cat. 2. Veratridine (10(-4) M) markedly enhanced catecholamine secretion evoked by acetylcholine (ACh, 10(-4) M) during perfusion with Ca2(+)-free Locke solution containing hexamethonium (10(-3) M). The enhancement tended to be larger for noradrenaline secretion than for adrenaline secretion. Qualitatively the same result was obtained in the response to pilocarpine (5 x 10(-4) M). 3. Ouabain (10(-4) M) also enhanced ACh- and pilocarpine-induced catecholamine secretions, especially noradrenaline secretion in the absence of extracellular Ca2+. 4. Tetrodotoxin (10(-6) M) blocked the enhancing effect of veratridine on ACh-induced catecholamine secretion, but not that of ouabain in the absence of extracellular Ca2+. 5. When NaCl was replaced with sucrose, there was no secretory response to ACh regardless of the presence or absence of veratridine or ouabain. However, when ouabain, but not veratridine, was infused with Na+ before the replacement of NaCl, the response to ACh was substantially augmented. 6. These results indicate that Na+ is essential in the initiation of muscarinic receptor-mediated catecholamine secretion and its enhancement by veratridine and ouabain in the absence of extracellular Ca2+. Both drugs seem to increase the intracellular concentration of Na+ through different mechanisms and result in increases in the efficiency of Ca2+ mobilization from intracellular Ca2+ pools linked to muscarinic receptors.
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Affiliation(s)
- H Teraoka
- Department of Pharmacology, Faculty of Veterinary Medicine, Hokkaido University, Sapporo, Japan
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26
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Teraoka H, Nakazato Y, Ohga A. Sodium ions inhibit the stimulant action of caffeine on catecholamine secretion from adrenal chromaffin cells of the guinea pig. Neurosci Lett 1990; 108:179-82. [PMID: 2304627 DOI: 10.1016/0304-3940(90)90727-q] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Catecholamine secretion evoked by caffeine (40 mM) was markedly enhanced by replacing NaCl in the medium with sucrose or KCl in the absence, but not in the presence, of extracellular Ca2+ and Mg2+ in both perfused adrenal glands and isolated chromaffin cells of the guinea pig. The response to caffeine declined on repetition, but was restored completely after readmission of Ca2+. These results indicate that extracellular Na+ inhibits caffeine from stimulating catecholamine secretion, which may be mediated by a release of Ca2+ from intracellular storage sites in the adrenal chromaffin cells in the presence of extracellular Ca2+ and/or Mg2+.
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Affiliation(s)
- H Teraoka
- Department of Pharmacology, Faculty of Veterinary Medicine, Hokkaido University, Sapporo, Japan
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27
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Satoh E, Nakazato Y. [3H]acetylcholine release and the change in cytosolic free calcium level induced by high K+ and ouabain in rat brain synaptosomes. Neurosci Lett 1989; 107:284-8. [PMID: 2616040 DOI: 10.1016/0304-3940(89)90832-x] [Citation(s) in RCA: 6] [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
High K+ (50 mM) increased both [3H]acetylcholine ([3H]ACh) release and cytosolic free calcium level ([Ca2+]i) in rat brain synaptosomes in the presence of extracellular Ca2+. Ouabain (5 x 10(-8) to 5 x 10(-4) M) also caused a dose-dependent increase in [3H]ACh release, but not in [Ca2+]i, in the absence of Ca2+. The effects of high K+ and ouabain on [3H]ACh and/or [Ca2+]i, were inhibited by the intracellular Ca2+ antagonist TMB-8 (10(-4) M). These results suggest that unlike high K+, ouabain increases transmitter release from nerve endings through a mechanism which is independent of [Ca2+]i, but sensitive to TMB-8.
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Affiliation(s)
- E Satoh
- Department of Veterinary Pharmacology, Obihiro University of Agriculture and Veterinary Medicine, Japan
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