Background: Mice with a knockout (KO) of muscle LIM protein (MLP) exhibit many morphologic and clinical features of human cardiomyopathy. In humans, MLP-expression is downregulated both in ischemic and dilative cardiomyopathy. In this study, we investigated the effects of MLP on the electrophysiologic phenotype in vivo and on outward potassium currents.
Methods And Results: MLP-deficient (MLPKO) and wild-type (MLPWT) mice were subjected to long-term electrocardiogram (ECG) recording and in vivo electrophysiologic study. The whole-cell, patch-clamp technique was applied to measure voltage dependent outward K+ currents in isolated cardiomyocytes. Long-term ECG revealed a significant prolongation of RR mean (108 +/- 9 versus 99 +/- 5 ms), P (16 +/- 3 versus 14 +/- 1 ms), QRS (17 +/- 3 versus 13 +/- 1 ms), QT (68 +/- 8 versus 46 +/- 7 ms), QTc (66 +/- 6 versus 46 +/- 7 ms), JT (51 +/- 7 versus 34 +/- 7 ms), and JTc (49 +/- 5 versus 33 +/- 7 ms) in MLPKO versus MLPWT mice (P < .05). During EP study, QT (80 +/- 8 versus 58 +/- 7 ms), QTc (61 +/- 6 versus 45 +/- 5 ms), JT (62 +/- 9 versus 43 +/- 6 ms), and JTc (47 +/- 5 versus 34 +/- 5 ms) were also significantly prolonged in MLPKO mice (P < .05). Nonsustained VT was inducible in 9/16 MLPKO versus 2/15 MLPWT mice (P < .05). Analysis of outward K+ currents in revealed a significantly reduced density of the slowly inactivating outward K+ current IK, slow in MLPKO mice (11 +/- 5 pA/pF versus 18 +/- 7 pA/pF; P < .05).
Conclusion: Mice with KO of MLP exhibit significant prolongation of atrial and ventricular conduction and an increased ventricular vulnerability. A reduction in repolarizing outward K+ currents may be responsible for these alterations.
Download full-text PDF |
Source |
|---|---|
| http://dx.doi.org/10.1016/j.cardfail.2007.04.015 | DOI Listing |
Publication Analysis
Top Keywords
Similar Publications
McGrath MAC Versus Three-Dimensional Printed Video Laryngoscopes: A Randomized, Manikin-Simulated Noninferiority Controlled Study with Medical Students.
Anesth Analg
February 2025
From the Department of Surgical Specialties and Anesthesiology of São Paulo State University (UNESP), Medical School, Botucatu, Brazil.
Background: Proficiency in endotracheal intubation (ETI) is essential for medical professionals and its training should start at medical schools; however, large caseload may be required before achieving an acceptable success rate with direct laryngoscopy. Video laryngoscopy has proven to be an easier alternative for intubation with a faster learning curve, but its availability in medical training may be an issue due to its high market prices. We devised a low-cost 3-dimensionally printed video laryngoscope (3DVL) and performed a randomized trial to evaluate if the intubation success rate on the first attempt with this device is noninferior to a standard commercially available video laryngoscope (STVL).
View Article and Find Full Text PDFTrifluridine/Tipiracil (FTD/TPI) in Metastatic Colorectal Cancer in Hong Kong: A Territory-Wide Cohort Study.
Adv Ther
January 2025
Centre of Cancer Medicine and University Department of Medicine, The University of Hong Kong, Hong Kong SAR, China.
Introduction: Randomized phase III trials showed that using trifluridine/tipiracil (FTD/TPI) in patients with pre-treated metastatic colorectal cancer (mCRC) conferred survival benefit versus placebo. Here, we investigated the effectiveness and safety of FTD/TPI and sought to identify prognostic factors among the mCRC population in Hong Kong.
Methods: A non-interventional, retrospective, multicenter cohort study enrolled patients with mCRC who received FTD/TPI in seven public hospitals in Hong Kong between 2016 and 2020.
Patterns and predictors of statin therapy after ischemic stroke and TIA: insights from the LIPYDS multicenter study.
Neurol Sci
January 2025
Department of Neurology and Stroke Unit, ASST Grande Ospedale Metropolitano Niguarda, Piazza Ospedale Maggiore 3, Milan, 20162, Italy.
Background: Patients with ischemic stroke (IS) or TIA face an elevated cardiovascular risk, warranting intensive lipid-lowering therapy. Despite recommendations, adherence to guidelines is suboptimal, leading to frequent undertreatment. This study aims to evaluate the statin use after IS and TIA.
View Article and Find Full Text PDFPDO screw threads versus fractional CO laser, after subcision, for atrophic acne scar remodelling: a randomized group-based comparative study.
Arch Dermatol Res
January 2025
Department of Dermatology, Venereology, and Andrology, Faculty of Medicine, Al-Azhar University, Cairo, Egypt.
Atrophic acne scars present a significant therapeutic challenge. While subcision with various adjunctive treatments, including fractional CO₂ lasers and polydioxanone (PDO) threads, has been employed for scar remodeling, comparative evidence on their efficacy remains limited. This study aims to compare the clinical efficacy and patient satisfaction between subcision with fractional CO₂ laser and subcision with PDO screw threads in managing atrophic acne scars.
View Article and Find Full Text PDFComparative study between fractional laser assisted drug delivery of botulinum toxin versus botulinum toxin injection in primary palmar and axillary hyperhidrosis.
Arch Dermatol Res
January 2025
Department of Dermatology, Medical Research and Clinical Studies Institute, National Research Centre, Giza, Egypt.
Palmar hyperhidrosis is common condition that is challenging to treat. Nonsurgical treatments include topical antiperspirants, iontophoresis, anticholinergic drugs and botulinum toxin injections. To evaluate the safety and efficacy of ablative fractional laser therapy, combined with topically applied botulinum toxin versus its injection for the treatment of hyperhidrosis.
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!