Some anti-malarials have deleterious effects upon the heart. The actions of two of these, chloroquine and quinacrine, were compared on isolated guinea-pig atria and Langendorff preparations to assess their effects on several calcium pools. Both compounds decreased developed tension in a concentration (chloroquine 10-100 microM; quinacrine 3-100 microM) and time-dependent manner, with quinacrine being twice as potent as potent as chloroquine. Ventricular muscle was much more sensitive to chloroquine than was atrial muscle. Concentrations of chloroquine, comparable to that found in the serum of patients ingesting toxic doses, caused significant inhibition of developed tension. The effects of chloroquine were almost completely reversed on washout; quinacrine, however, was less readily reversible. Chloroquine also had a direct negative chronotropic effect, substantially reduced force-frequency relationships and developed tension in partially depolarized atrial preparations; while post-rest contraction and the positive inotropic effect of ouabain were unaffected. Increases in extracellular calcium antagonized the negative inotropic effect. Quinacrine had a marked effect on post-rest contraction and attenuated the positive inotropic action of ouabain. It is concluded that the action of chloroquine may involve a superficial calcium pool, while quinacrine may act upon several calcium pools.
Download full-text PDF |
Source |
|---|---|
| http://dx.doi.org/10.1016/0014-2999(90)90108-i | DOI Listing |
Publication Analysis
Top Keywords
Similar Publications
Enhancing Droplet Spreading on a Hydrophobic Plant Surface by Surfactant/Cellulose Nanocrystal Complexes.
ACS Nano
January 2025
Department of Chemical Engineering, Waterloo Institute for Nanotechnology, University of Waterloo, 200 University Avenue West, Waterloo, Ontario N2L 3G1, Canada.
A surfactant is an efficient and common additive used to enhance the spreading of droplets on hydrophobic surfaces. However, a high surfactant concentration is required to achieve the desired performance, resulting in environmental pollution and increased costs. Additionally, the pesticide loading capacity of surfactants at low concentrations (below their critical micelle concentrations) is a concern.
View Article and Find Full Text PDFBenzenedialdehyde-crosslinked gelatin nanoparticles for Pickering emulsion stabilization.
Curr Res Food Sci
December 2024
Medical Food Laboratory, Shanghai Key Laboratory of Pediatric Gastroenterology and Nutrition, Shanghai Institute for Pediatric Research, Xinhua Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, 200092, China.
In this work, three types of benzenedialdehydes (1,2-, 1,3-, and 1,4-BDAs) were used to prepare BDA-crosslinked gelatin nanoparticles and the 1,2-BDA-crosslinked gelatin nanoparticle was explored to stabilize fish oil-loaded Pickering emulsions. The nanoparticle preparation was dependent on both pH and crosslinker types. 1,2-BDA and preparation pH of 12.
View Article and Find Full Text PDFMaternity behind and beyond bars: analysis from the perspective of protection bioethics.
Rev Bras Enferm
January 2025
Universidade Federal de Santa Catarina. Florianópolis, Santa Catarina, Brazil.
Objective: to analyze how motherhood is expressed in female prison units from the perspective of Bioethics of Protection.
Method: qualitative research with an ethnographic approach, developed in two women's prison units. Participantes were: six mothers deprived of liberty, 15 health professionals, and nine prison officers.
Enhanced remediation of oil-contaminated mineral sand by the controlled release of a surfactant from calcium alginate capsules.
Environ Technol
January 2025
Department of Civil Engineering, The University of Hong Kong, Hong Kong SAR, People's Republic of China.
The remediation of oil-contaminated soil poses significant environmental challenges, often necessitating innovative approaches for effective and sustainable solutions. This study focuses on the synthesis, characterisation, and application of biodegradable capsules loaded with surfactant for enhanced oil remediation of a clean sand. By controlling the release properties of capsules, the research aims to overcome the limitations of conventional surfactant-based remediation methods, such as rapid washout and reduced efficacy over time.
View Article and Find Full Text PDFCivil Disobedience in Democratic Education.
Integr Psychol Behav Sci
January 2025
University of Delaware, Newark, DE, USA.
The study's goal was to examine the tension between democratic school governance, requiring its participants to obey school rules, even though they might disagree with those rules, and personal responsibility, requiring the participants to act morally, in accordance with their conscience and their sense of what is right and makes sense for them, regardless of the democratic nature of the imposed school rules. This examination was based on three sources: 1) three Open Symposia with American and Russian democratic educationalists, 2) my review of the existing literature on civil disobedience and democratic education, and 3) my empirical study based on the interviews of participants of an American private democratic school, known as The Circle School, regarding their instances of civil disobedience. The three Open Symposia allowed me to develop a working definition of civil disobedience as a particular principled disobedience.
View Article and Find Full Text PDFWant AI Summaries of new PubMed Abstracts delivered to your In-box?
Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!