Department Of Physiological Sciences Research Articles

From apples to airways - why gravity matters.

Experimental PhysiologyVolume 107, Issue 7 p. 745-746 VIEWPOINT From apples to airways – why gravity matters Leah R. Reznikov, Corresponding Author Leah R. Reznikov [email protected] orcid.org/0000-0002-4074-9070 Department of Physiological Sciences, University of Florida, Gainesville, FL, USA Email: [email protected]Search for more papers by this author Leah R. Reznikov, Corresponding Author Leah R. Reznikov [email protected] orcid.org/0000-0002-4074-9070 Department of Physiological Sciences, University of Florida, Gainesville, FL, USA Email: [email protected]Search for more papers by this author First published: 28 December 2020 https://doi.org/10.1113/EP089333Citations: 1 Edited by: Ken O'Halloran Linked articles: This Viewpoint highlights an article by Kizhakke Puliyakote et al. To read this paper, visit https://doi.org/10.1113/EP089037. Read the full textAboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL No abstract is available for this article.Citing Literature Volume107, Issue71 July 2022Pages 745-746 RelatedInformation

Phytochemical Profile and Investigation of the Spasmolytic Activity of Hydroalcoholic Extract of Syzygium cumini (L.) Skeels Seeds

Aims: Perform the phytochemical analysis and investigate the spasmolytic activity of the hydroalcoholic extract obtained from S. cumini seeds (EHS-SC).
 Study Design: Qualitative phytochemical analysis and test of the EHS-SC on isolated smooth muscles (aorta, trachea, jejunum and uterus) of rat, to value effect relaxant and/or inhibitor.
 Place and Duration of Study: Pharmacognosy Laboratory II (Pharmacy course) and Pharmacology Research and Post-Graduate Laboratory (Department of Physiological Sciences) of the Federal University of Maranhão, between January 2017 and July 2018.
 Methodology: EHS-SC was submitted to phytochemical analysis and changes in color, fluorescence and absence or presence of precipitate were observed. The smooth muscle segments were suspended (tension of 1 g) in glass vats containing specific saline solution, at an appropriate temperature and after stabilization period, was stimulated by a suitable contractile agent to observe the effect of EHS-SC in the phasic and/or tonic component.
 Results: EHS-SC showed the majority presence of phenols, steroids, alkaloids and flavonoids (flavones, xanthones, flavonols) and was more potent in inhibiting phasic contractions induced by 10-6 M carbachol (CCh) in isolated rat jejunum (Emax: 83.5 ± 6.7%; n = 3). In addition, the EHS-SC (81.0; 243.0 and 729 µg/mL) antagonized the CCh effect (n = 4), increasing the EC50 (6.5 ± 1.3 x 10-7 M) of the CCh to 8.5 ± 1.1; 18.5 ± 3.4 and 40.5 ± 7.4 x 10-7 M and reducing the Emax (100%) of the CCh to 82.9 ± 10.5; 67.6 ± 6.0 and 10.1 ± 8.3%.
 Conclusion: Spasmolytic activity may be combined with antimicrobial and antidiarrheal activity according to literature data, where they show that the seeds have the same secondary metabolites, signaling the therapeutic potential for the treatment of colic and/or diarrhea.

ABO Blood Group System: Its Association with Anthropometric Indices among Young Adults of Yoruba Ethnicity

Introduction: The ABO blood group system is unique in immunology and haematology because it is the only system in which antibodies are consistently and predictably present in the serum of normal individuals whose red cells lack the antigens. Several epidemiological studies have reported that the distribution of different ABO blood groups vary markedly among the populations of different geographical areas reflecting racial differences.
 Aims: The aim of this study was to determine the association between ABO blood group and anthropometric indices among apparently healthy young adults of Yoruba ethnicity.
 Study Design: This is a cross-sectional descriptive study.
 Place and Duration of Study: The study was carried out at Department of Physiological Sciences and University Health Centre, Obafemi Awolowo University, Ile-Ife between May 2016 to June 2017.
 Methodology: Eighty apparently healthy young adults who were purposely selected participated in the study after screening for the ABO blood groups following the standard protocol. They were divided into four equal groups; 20 in each of blood groups A, B, AB and O who were age- and sex - matched. The weight (kg) and height (cm) of the participants were measured following standard protocol. Body mass index (BMI) and body surface area (BSA) were estimated from weight and height using Quetelex and Mosteller formulae respectively. Chi-square was used to compare grouped data while the comparison of means of parameters among the four blood groups was done using Analysis of Variance (ANOVA). A p-value of < 0.05 was taken statistically significant.
 Results: Out of the total 80 participants, 15% were males. The mean ± SD of height(m) of participants with blood groups A, B, O and AB were 1.65 ± 0.06, 1.63 ± 0.08, 1.62 ± 0.08 and 1.63 ± 0.08 (F= 0.349, p= 0.790) respectively. The mean ± SD of weight(kg) of the participants with blood group A,B, O and AB were 56.15 ± 8.71, 56.00 ± 11.21, 57.10 ± 12.73 and 58.05 ± 10.35 (F= 0.154, p= 0.927) respectively. The mean ± SD of BMI in kg/m2 for blood groups A, B, O and AB were 20.74 ± 3.22, 20.86 ± 2.91, 21.79 ± 5.10 and 21.91 ± 4.21 (F= 0.472, p= 0.703) respectively while the mean ± SD of BSA (m2) for blood group A, B, O and AB were 1.60 ± 0.12, 1.59 ± 0.19, 1.60 ± 0.18 and 1.62 ± 0.15 (F= 0.098, p= 0.961) respectively.
 Conclusion: AB Blood group may be predisposed to metabolic syndrome due to the higher mean of weight, BSA and BMI found in this group.

Virtual environments and virtual humans for military mild traumatic brain injury and posttraumatic stress disorder: an emerging concept.

From the U.S. Department of Veteran’s Affairs, North Florida/South Georgia Veterans Health System, Gainesville, Florida (CEL,EPS, LL); Department of Occupational Therapy (CEL) andDepartment of Computer and Information Science andEngineering, College of Engineering (SH, BCL), University ofFlorida, Gainesville; Department of Physiological Sciences,College of Veterinary Medicine (EPS), and Departments of Clinicaland Health Psychology (MM) and Occupational Therapy (LL),College of Public Health and Health Professions, University ofFlorida, Gainesville; and U.S. Department of Veteran’s Affairs,Charlotte, North Carolina (DO).Supported by (1) W81XWH-08-2-0194 PT073664 Design ofEffective Therapeutic Interventions for Mild TBI/PTSD usingInteractive Virtual World Environments, CDMRP/DoD9.15.08-9.14.09; (2) Development of Virtual Humans For PTSDand mTBI: Rehabilitation Outcomes Research Center 2010Y2011;and (3) 1I01RX000339-01A3, Virtual Environments forTherapuetic Solutions (VETS) mTBI/PTSD Phase II, VA RR&D,$824,835, 4.1.13-3.30.16.Financial disclosure statements have been obtained, and noconflicts of interest have been reported by the authors or by anyindividuals in control of the content of this article.0894-9115/15/9404-e31American Journal of Physical Medicine & RehabilitationCopyright * 2015 Wolters Kluwer Health, Inc. All rights reserved.

Functional neural-bone marrow pathways: implications in hypertension and cardiovascular disease.

Treatment-resistant hypertension (TRHT) is characterized by persistently high arterial blood pressure (BP), partly as a result of a dysfunctional autonomic nervous system (ANS), wherein sympathetic drive/norepinephrine spillover is increased and parasympathetic drive is decreased.1–3 The difficulty in treatment of TRHT arises precisely from this partly neurogenic component because the available drug therapies do not target the central nervous system (CNS) directly. Because of this and despite recent advances in techniques such as renal denervation and carotid baroreceptor activation,4,5 successful treatment and long-term control of TRHT remain challenging.6 In an attempt to develop more effective treatments, many groups are investigating specific causes of TRHT. A large body of experimental evidence implicates both genetic and environmental influences, such as salt sensitivity and elevated systemic renin–angiotensin system (RAS) activity7–14 in the pathophysiology of this disease. Furthermore, a majority of studies point to dysregulations in the activity within the cardiorespiratory brain regions as a reason for increased sympathetic and decreased parasympathetic drive to the peripheral organs,14–21 resulting in end-organ damage,21–25 vascular/endothelial dysfunction,26,27 and hormonal imbalance,28 which perpetuate the pathophysiology and complicate treatment strategies. Despite our increasing understanding of TRHT, the origins of this brain dysregulation remain largely unknown. Recently, the activity of the immune system29–31 and neuroimmune pathways in patients with hypertension and animal models of hypertension has been highlighted.32–36 Studies suggest that both the sympathetic and the parasympathetic arms of the ANS can exert their influence on the activity of the immune organs, tissues, and cells, and that it is the dysfunctional ANS-immune communication that may lead to hypertension and CVD.35–40 The aim of this review is to summarize the latest advances in this …

Effects of glucocorticoids and exercise on pancreatic β‐cell function and diabetes development: comments on Beaudry and Riddel

Department of Physiological Sciences,Centre of Biological Sciences,Federal University of SantaCatarina (UFSC),88040-900 Florianopolis, SC, Brazil*Correspondence to: Alex Rafacho,Department of PhysiologicalSciences, Centre of BiologicalSciences, Federal University of SantaCatarina (UFSC), 88040-900Florianopolis, SC, Brazil.E-mail: alex.rafacho@ufsc.br

Mechanisms of neurotoxicity and implications for neurological disorders

Keywords: chemical contaminants, neurodegeneration, neurodevelopment, neuroinflammation, neurotoxicty.On 13 July 2012, in conjunction with the 8th FENSForum of Neuroscience in Barcelona, Dr. JordiLlorens and I organized a Satellite Event in theform of a 1-day symposium. The main focus of thesymposium was on the mechanisms of neurotox-icity potentially involved in neurodegenerative dis-eases or neurodevelopmental disorders. Aspectsincluding gene–environment interactions, specificcellular alterations and neurodevelopmental impli-cations were covered by internationally recognizedexperts in their respective field. Reviews based onsix of the oral presentations from invited speakersare included in this issue of the Journal of InternalMedicine.The review by Dr. Julie Andersen, Buck Institutefor Age Research, Novato CA, USA, discusses thepossible link between environmental stress,aging, glial cell senescence and Parkinson’s dis-ease [1]. Certain chronic environmental expo-sures have been linked to the age-relateddevelopment of Parkinson’s disease neuropathol-ogy. Neuronal damage is believed to involve theinduction of neuroinflammatory events mediatedby glial cell activation. Senescent cells accumu-late with age, and they express a senescence-associated secretory phenotype (SASP) connectedto the secretion of many inflammatory cytokines,growth factors and proteases. Andersen proposesthat senescent glia could contribute to age-related neurodegeneration by creating a chroni-cally inflamed milieu. If correct, this novelpotential link between glial senescence and Par-kinson’s disease could change the current under-standing on the role of glial cells in age-relatedneurodegenerative diseases. In particular envi-ronmental stressors associated with Parkinson’sdisease, such as paraquat and MPTP, may act inpart by eliciting senescence and SASP expressionby glial cells in the aging brain, thereby contrib-uting to the characteristic decline in neuronalintegrity that occurs in the disorder.Dr. Rosario Moratalla, Instituto Cajal, CSIC,Madrid,describesinherreviewtheroleofdopaminereceptors in the neurotoxicity of the synthetic drugmethamphetamine [2]. Despite its neurotoxiceffects including loss of dopaminergic fibres andcell bodies, methamphetamine is consumed bymillions of users. There is evidence from clinicalreports suggesting that methamphetamine abusersare predisposed to Parkinson’s disease. The mech-anism of methamphetamine neurotoxicity involvesdopamine receptors. In fact, genetic inactivation ofD1orD2receptorsubtypesprotectsagainstthelossof dopaminergic fibres in the striatum and loss ofdopaminergic neurons in the substantia nigrainduced by methamphetamine. The protectiongiven by D1 receptor inactivation is due to blockadeof hyperthermia, lower dopamine content and turn-over,andhigherlevelsofstoredvesiculardopaminein D1 receptor

Determination of lymphocytes subpopulations in peripheral blood cells of dogs with atopic dermatitis

Event Abstract Back to Event Determination of lymphocytes subpopulations in peripheral blood cells of dogs with atopic dermatitis Alicja Majewska1*, Kourou Dembele2, Malgorzata Gajewska1 and Tomasz Motyl1 1 Warsaw University of Life Sciences - SGGW, Department of Physiological Sciences, Faculty of Veterinary Medicine, Poland 2 Warsaw University of Life Sciences - SGGW, Department of Small Animal Diseases with Clinic, Faculty of Veterinary Medicine, Poland Canine atopic dermatitis (AD) is a genetically-predisposed inflammatory and pruritic allergic skin disease, with clinical features commonly associated with IgE-antibodies to environmental allergens. Th1 and Treg lymphocytes play an important role in AD, regulating immune response i.e. by inhibiting the development of allergic responses of Th2 cells. During early phases of AD Th2 response predominates and is followed by Th1 domination in chronic AD. The aim of this study was to determine the profile of lymphocyte subpopulations in peripheral blood mononuclear cells (PBMC) in dogs with AD. Twenty dogs with AD (patients of Small Animal Clinic) were included in this study. Diagnosis was made based on Willemse’s and Prélaud’s criteria, confirmed by serological allergy tests and intradermal skin tests. Three healthy dogs were included as controls. PBMC were isolated from blood and analyzed using flow cytometry. The most commonly encountered positive results were against house-dust mites (over 70%), and less frequently against various pollens: grass weed, tree. Percentage of Th1 cells was higher in atopic dogs (12%) compared with controls (6.7%). The Th1/Th2 ratio equaled 3 in AD dogs, whereas 1.3 in controls. The number of Treg lymphocytes was two times higher in atopic dogs. Tc cells population was also elevated in AD dogs vs. controls (19.5% vs. 16.8%). B cells percentage was lower in AD dogs. To summarize, dogs with AD had increased Th1 and Tc subpopulations, and decreased number of Th2 and B cells, indicating that a transition from early humoral to cell-mediated immunity occurred in the examined patients. Acknowledgements This work was supported by a grant no. NN308 575940 from the National Science Centre, Poland Keywords: atopic dermatitis, canine, Lymphocytes, allergy, T cells subpopulations Conference: 15th International Congress of Immunology (ICI), Milan, Italy, 22 Aug - 27 Aug, 2013. Presentation Type: Abstract Topic: Immune-mediated disease pathogenesis Citation: Majewska A, Dembele K, Gajewska M and Motyl T (2013). Determination of lymphocytes subpopulations in peripheral blood cells of dogs with atopic dermatitis. Front. Immunol. Conference Abstract: 15th International Congress of Immunology (ICI). doi: 10.3389/conf.fimmu.2013.02.01149 Copyright: The abstracts in this collection have not been subject to any Frontiers peer review or checks, and are not endorsed by Frontiers. They are made available through the Frontiers publishing platform as a service to conference organizers and presenters. The copyright in the individual abstracts is owned by the author of each abstract or his/her employer unless otherwise stated. Each abstract, as well as the collection of abstracts, are published under a Creative Commons CC-BY 4.0 (attribution) licence (https://creativecommons.org/licenses/by/4.0/) and may thus be reproduced, translated, adapted and be the subject of derivative works provided the authors and Frontiers are attributed. For Frontiers’ terms and conditions please see https://www.frontiersin.org/legal/terms-and-conditions. Received: 25 Jul 2013; Published Online: 22 Aug 2013. * Correspondence: Dr. Alicja Majewska, Warsaw University of Life Sciences - SGGW, Department of Physiological Sciences, Faculty of Veterinary Medicine, Warsaw, Poland, alamaj@poczta.onet.pl Login Required This action requires you to be registered with Frontiers and logged in. To register or login click here. Abstract Info Abstract The Authors in Frontiers Alicja Majewska Kourou Dembele Malgorzata Gajewska Tomasz Motyl Google Alicja Majewska Kourou Dembele Malgorzata Gajewska Tomasz Motyl Google Scholar Alicja Majewska Kourou Dembele Malgorzata Gajewska Tomasz Motyl PubMed Alicja Majewska Kourou Dembele Malgorzata Gajewska Tomasz Motyl Related Article in Frontiers Google Scholar PubMed Abstract Close Back to top Javascript is disabled. Please enable Javascript in your browser settings in order to see all the content on this page.

Terapia a través de la danza y el movimiento en mujeres con cáncer de mama: el impacto psicofísico del proceso empático

Objectives: To describe the therapeutic process and possible influence of mirror neurons in kinesthetic empathy using dance movement therapy for breast cancer. Method: Case study methodology was used. A patient diagnosed with breast cancer two years previously was referred to the Department of Physiological Sciences II, University of Barcelona. She attended a dance movement therapy intervention for 5 months (1 hour per week, 20 sessions).The patient’s medical history and a therapist’s records were reviewed. Result: The patient showed an improvement in perceived mental and physical well-being after participating in the program of dance movement therapy. This type of intervention facilitated the collection of physical and psychological patient information. Empathy was vital to this process. Conclusions: The perceived well-being expressed by the patient throughout the sessions enhances the clinical significance of dance movement therapy. It is recommended that a trial is undertaken to assess the effectiveness of dance movement therapy on breast cancer patients’ mental and physical well-being.

QUANTITATIVE PROTEOMICS FOR FISH NEUROENDOCRINOLOGY AND NEUROTOXICOLOGY

QUANTITATIVE PROTEOMICS FOR FISH NEUROENDOCRINOLOGY AND NEUROTOXICOLOGY

EEG and vagal tone degradation during nocturnal sleep in abstinent alcohol dependence

a Cousins Center for Psychoneuroimmunology, Semel Institute for Neuroscience and Human Behavior, UCLA David Geffen School of Medicine, University of California, Los Angeles, CA 90095-7057, USA b Department of Neurobiology, UCLA David Geffen School of Medicine, University of California, Los Angeles, CA 90095-7057, USA c Department of Physiological Sciences, UCLA David Geffen School of Medicine, University of California, Los Angeles, CA 90095-7057, USA

Accumulation of Dietary DDE and Dieldrin by Largemouth Bass, Micropterus salmoides floridanus

1 Applied Pharmacology and Toxicology, Inc., 2250 NW 24 Avenue, Gainesville, FL 32605, USA 2 Department of Fisheries and Aquatic Sciences, University of Florida College of Agricultural and Life Sciences, 7922 NW 71 Street, Gainesville, FL 32653, USA 3 Department of Physiological Sciences, University of Florida College of Veterinary Medicine, Post Office Box 100144, Gainesville, FL 32611, USA 4 United States Geological Survey, Biological Resources Division, Center for Aquatic Resource Studies, 7920 NW 71 Street, Gainesville, FL 32653, USA

In Vivo Whole‐Cell Patch‐Clamp Recordings from Purkinje Cells and Interneurons

Annals of the New York Academy of SciencesVolume 978, Issue 1 p. 523-524 In Vivo Whole-Cell Patch-Clamp Recordings from Purkinje Cells and Interneurons Synaptic Integration of Peripheral Input HENRIK JÖRNTELL, Corresponding Author HENRIK JÖRNTELL Department of Physiological Sciences, Tornavaägen 10, SE-221 84 Lund, SwedenAddress for correspondence: Dr. Henrik Jörntell, Department of Physiological Sciences, Section for Neurophysiology, BMC F10, Tornavägen 10, SE-221 84 Lund, Sweden. Voice: +46 46 222 77 64; fax: +46 46 222 45 46; [email protected].Search for more papers by this authorCARL-FREDRIK EKEROT, CARL-FREDRIK EKEROT Department of Physiological Sciences, Tornavaägen 10, SE-221 84 Lund, SwedenSearch for more papers by this author HENRIK JÖRNTELL, Corresponding Author HENRIK JÖRNTELL Department of Physiological Sciences, Tornavaägen 10, SE-221 84 Lund, SwedenAddress for correspondence: Dr. Henrik Jörntell, Department of Physiological Sciences, Section for Neurophysiology, BMC F10, Tornavägen 10, SE-221 84 Lund, Sweden. Voice: +46 46 222 77 64; fax: +46 46 222 45 46; [email protected].Search for more papers by this authorCARL-FREDRIK EKEROT, CARL-FREDRIK EKEROT Department of Physiological Sciences, Tornavaägen 10, SE-221 84 Lund, SwedenSearch for more papers by this author First published: 27 January 2006 https://doi.org/10.1111/j.1749-6632.2002.tb07603.xRead the full textAboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Volume978, Issue1THE CEREBELLUM: RECENT DEVELOPMENTS IN CEREBELLAR RESEARCHDecember 2002Pages 523-524 RelatedInformation

Effect of carbopol 934P on the clinical course of active ulcerative colitis: B.J. Rankin, ∗ [formula omitted], C.O. Record, ∗J. Green, ∗M.C. Allison, ∗G.T. Williams, †P.W. Dettmar, †P. Dickson, J.P. Pearson and A. Allen. Department of Physiological Sciences, University of Newcastle Upon Tyne, UK, ∗Department of Medicine, Royal Gwent Hospital, Newport, Gwent, UK. †Reckitt and Colman Products Ltd, Hull, UK

Effect of carbopol 934P on the clinical course of active ulcerative colitis: B.J. Rankin, ∗ [formula omitted], C.O. Record, ∗J. Green, ∗M.C. Allison, ∗G.T. Williams, †P.W. Dettmar, †P. Dickson, J.P. Pearson and A. Allen. Department of Physiological Sciences, University of Newcastle Upon Tyne, UK, ∗Department of Medicine, Royal Gwent Hospital, Newport, Gwent, UK. †Reckitt and Colman Products Ltd, Hull, UK

Molecular cloning of the gene encoding a myotoxin from the venom of the broad-banded copperhead (Agkistrodon contortrix laticinctus): C. L. Ownby and Q. Li (Department of Physiological Sciences, Oklahoma State University, Stillwater, OK 74078, U.S.A.)

Molecular cloning of the gene encoding a myotoxin from the venom of the broad-banded copperhead (Agkistrodon contortrix laticinctus): C. L. Ownby and Q. Li (Department of Physiological Sciences, Oklahoma State University, Stillwater, OK 74078, U.S.A.)

Purification and characterization of two high molecular weight hemorrhagic toxins from Crotalus viridis viridis venom using monoclonal antibodies: Q. Li, T. R. Colberg and C. L. Ownby (Department of Physiological Sciences, Oklahoma State University, Stillwater, OK. 74078, U.S.A.)

Purification and characterization of two high molecular weight hemorrhagic toxins from Crotalus viridis viridis venom using monoclonal antibodies: Q. Li, T. R. Colberg and C. L. Ownby (Department of Physiological Sciences, Oklahoma State University, Stillwater, OK. 74078, U.S.A.)

Comparison of the venoms of the South American (Crotalus durissus terrificus) and Mojave (Crotalus scultulatus scutulatus) rattlesnakes: C. L. Ownby and T. R. Colberg (Department of Physiological Sciences, Oklahoma State University, Stillwater, OK, 74078, U.S.A.).

Comparison of the venoms of the South American (Crotalus durissus terrificus) and Mojave (Crotalus scultulatus scutulatus) rattlesnakes: C. L. Ownby and T. R. Colberg (Department of Physiological Sciences, Oklahoma State University, Stillwater, OK, 74078, U.S.A.).

Can in vitro techniques elucidate the mechanism of labour?

51 CAN IN VITRO TECHNIQUES ELUCIDATE THE MECHANISM OF LABOUR? *S. Thornton , J. I. Gillespie, J. R. Greenwell, E. Davies *W. Dunlop Department of Physiological Sciences and *Department of Obstetrics, The Medical School, The University, Newcastle upon Tyne, UK. The factors controlling human labour remain elusive, due in part to our ignorance of the physiological mechanisms of uterine contraction. The underlying mechanism is important since its determination would allow a rational approach to the pharmacological manipulation of uterine activity. Within the myometrial cell, intracellular calcium ([Ca*+]i) is of fundamental importance in the initiation of contraction. In addition to controlling actin and myosin interaction it is the final mediator of numerous intracellular second messengers. Invasive physiological studies are inappropriate during human labour. We have developed an approach using isolated myometrial cells. These can retain the characteristics of the parent tissue.’ Cell culture has been combined with fluorescent indicator techniques in order to determine [Ca*+]i in single human myometrial cells. Myometrial biopsies were obtained, with informed consent, following hysterectomy or at caesarean section. Cells were separated by enzymatic digestion and cultured in 5% CO, and 95% air. Once confluent, cells were plated onto glass coverslips and studied after a further 3-4 days culture. Calcium was measured by loading cells with a calcium-sensitive fluorescent indicator dye (Fura-2) and the change in fluorescence ratio determined in single cells by microspectrofluorimetry. The extracellular environment was manipulated as required. Application of oxytocin (OT) or prostaglandin E, (PGE,) caused a transient increase in [Ca*+]i. In 4 of the 200 cells studied, spontaneous transient increases in [Ca’ ‘Ii occurred. This may represent spontaneous activity which occurs in the pregnant or nonpregnant uterus. Removal of extracellular calcium ([Ca*+]o) prevents calcium influx. In calcium-free medium, OT caused a small increase in [Ca’ ‘Ii but the response to PGE2 was completely prevented. This suggests that these agents have a different mechanism of action and intracellular stores of calcium may be released by OT but not PGE,. Spontaneous transient increases in [Ca* ‘Ii are prevented by removal of [Ca* +]o or application of 2mM Ni’ + (a calcium channel blocker) The OT antagonist (CAP 476) reduced the frequency of the transients. We conclude that physiological techniques can be used to determine the mechanism of action of agents which influence myometrial contractility: OT and PGE2 increase [Ca”+]i , but only OT releases intracellular stored calcium. Spontaneous increases in [Ca*+]i occur in some cells. These are caused by the influx of extracellular calcium and may by modified by the OT antagonist CAP 476.

Characterization of hemorrhagic toxins isolated from Agkistrodon contortrix laticinctus (broad banded copperhead) venom: Edward K. Johnson and Charlotte L. Ownby (Department of Physiological Sciences, Oklahoma State University, Stillwater, OK 74078, U.S.A.)

Characterization of hemorrhagic toxins isolated from Agkistrodon contortrix laticinctus (broad banded copperhead) venom: Edward K. Johnson and Charlotte L. Ownby (Department of Physiological Sciences, Oklahoma State University, Stillwater, OK 74078, U.S.A.)

Classification of myonecrosis induced by venom of the South American rattlesnake (Crotalus durissus terrificus): Charlotte L. Ownby and Sandra L. Reisbeck (Department of Physiological Sciences, Oklahoma State University, Stillwater, OK 74078, U.S.A.)

Classification of myonecrosis induced by venom of the South American rattlesnake (Crotalus durissus terrificus): Charlotte L. Ownby and Sandra L. Reisbeck (Department of Physiological Sciences, Oklahoma State University, Stillwater, OK 74078, U.S.A.)