Sökning: "verapamil"

Visar resultat 1 - 5 av 32 avhandlingar innehållade ordet verapamil.

  1. 1. Intestinal Permeability and Presystemic Extraction of Fexofenadine and R/S-verapamil

    Författare :Christer Tannergren; Hans Lennernäs; Dirk KF Meijer; Uppsala universitet; []
    Nyckelord :MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; Biopharmacy; Bioavailability; Fexofenadine; Verapamil; P-glycoprotein; CYP3A4; OATP; Enantioselective; Permeability; Caco-2; Intestinal perfusion; Biofarmaci; Biopharmacy; Biofarmaci;

    Sammanfattning : The main objective of this thesis was to investigate the in vivo relevance of membrane transporters and cytochrome P450 (CYP) 3A4-mediated metabolism in the intestine and liver for the bioavailability of drugs in humans after oral administration.In the first part of the thesis, the main transport mechanisms involved in the intestinal absorption and bioavailability were investigated for fexofenadine, a minimally metabolized drug, which is a substrate for P-glycoprotein (P-gp) and members of organic anion transporting polypeptide (OATP) family. LÄS MER

  3. 2. Calcium channel activity and force regulation in smooth muscle: Effects of polyamines and growth stimulation

    Författare :Maria Gomez; Kardiovaskulär forskning - immunitet och ateroskleros; []
    Nyckelord :MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; verapamil; tissue culture; portal vein; patch-clamp; calcium; spermidine; spermine; polyamines; excitation-contraction; smooth muscle; calcium channel; ionomycin.; Physiology; Fysiologi;

    Sammanfattning : The initial signal for contraction in smooth muscle is an increase in [Ca2+]i. Ca2+ ions can either enter the cytosol from the extracellular medium or be released from intracellular stores. Voltage-operated Ca2+ channels (VOC) play a dominant role in the activation of smooth muscle contraction. LÄS MER

  4. 3. Blood-Brain Barrier Transport : Investigation of Active Efflux using Positron Emission Tomography and Modelling Studies

    Författare :Stina Syvänen; Margareta Hammarlund-Udenaes; Mats Bergström; Gunnar Blomquist; Jashvant Unadkat; Uppsala universitet; []
    Nyckelord :Pharmaceutical biosciences; pharmacokinetics; P-glycoprotein; blood-brain barrier; modelling; PET; active efflux; species differences; [11C]verapamil; drug development; Farmaceutisk biovetenskap;

    Sammanfattning : This thesis examines the transport of exogenous molecules across the blood-brain barrier (BBB), focusing on active efflux, using positron emission tomography (PET), computer simulation and modelling. P-glycoprotein (P-gp) inhibition was studied using [11C]verapamil and [11C]hydroxyurea was investigated as a new marker for active efflux transport. LÄS MER

  5. 4. Intestinal permeability and presystemic metabolism of R/S-verapamil and fluvastatin

    Författare :Rikard Sandström; Uppsala universitet; []
    Nyckelord :MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; Pharmacy; FARMACI; PHARMACY; FARMACI; Biopharmaceutics; biofarmaci;

    Sammanfattning : The rate and extent of absorption of drugs from the gastrointestinal tract into the systemiccirculation is defined as the bioavailability. The bioavailability is influenced by a numberof pharmaceutical, pharmacokinetic, biochemical and physiological factors. Two key-variables are the intestinal permeability and the presystemic metabolism. LÄS MER

  7. 5. Studies on stable angina pectoris : risk indicators, prognosis and effects of verapamil or metoprolol treatment

    Författare :Claes Held; Karolinska Institutet; Karolinska Institutet; []
    Nyckelord :angina pectoris; haemostasis; fibrinolysis; inflammation; lipids; platelets; ultrasound; intima-media thickness; plaques; metoprolol; verapamil; prognosis; ;

    Sammanfattning : Hemostatic and fibrinolytic variables, inflammatory parameters, catecholamines and lipid parameters were studied at baseline, in a long-term prospective study of 809 patients with stable angina pectoris, and compared to results obtained in healthy control subjects (n=50). The prognostic implications of the various parameters at baseline were evaluated, as well as possible influences of drug treatment on these variables and their prognostic implications were studied. LÄS MER