Lycopus lucidus Turcz has been widely used as a traditional Oriental medicine (TOM) in Korea and China and prescribed for the enhancement of heart function. However, the precise effects have yet to be defined. The purpose of the present study was, therefore, to address whether the ethanol extract of Lycopus lucidus Turcz (ELT) has a positive inotropic effect. ELT-induced changes in atrial mechanical dynamics (pulse pressure, dp/dt, and stroke volume), and cAMP efflux were measured in perfused beating rabbit atria. Three active components, rosmarinic acid, betulinic acid, and oleanolic acid were identified in ELT by high performance liquid chromatography analysis. ELT increased atrial dynamics in a concentration-dependent manner without changes in atrial cAMP levels and cAMP efflux. The ELT-induced positive inotropic effect was blocked by inhibition of the L-type Ca(2+) channels and sarcoplasmic reticulum (SR). Inhibitors of β-adrenoceptors had no effect on the ELT-induced positive inotropic effect. The results suggest that ELT exerts a positive inotropic effect via activation of Ca(2+) entry through L-type Ca(2+) channel and Ca(2+) release from the SR in beating rabbit atria.
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http://dx.doi.org/10.1089/jmf.2012.2487 | DOI Listing |
BMC Pediatr
December 2024
Department of Pediatric Intensive Care, Faculty of Medicine, Cukurova University, Adana, Turkey.
Background: Albumin, a vital component in regulating human blood oncotic pressure, plays an important role in the prediction of prognosis in pediatric patients.Previous research identified significant differences in serum albumin levels of healthy and critically ill children.
Methods: The present study aims to investigate the correlation between albumin levels measured during pediatric intensive care unit(PICU) admission and clinical outcomes.
BMC Musculoskelet Disord
December 2024
Faculty of Rehabilitation, Kobe Gakuin University, 518 Arise, Ikawadani-cho, Nishi-ku, Kobe, Hyogo, 651-2180, Japan.
Background: Exercise-induced hypoalgesia (EIH) is characterized by a reduction in pain perception and sensitivity across both exercising and non-exercising body parts during and after a single bout of exercise. EIH is mediated through central and peripheral mechanisms; however, the specific effect of muscle contraction alone on EIH remains unclear. Moreover, previous studies on electrical muscle stimulation (EMS) have primarily focused on local analgesic effects, often relying on subjective pain reports.
View Article and Find Full Text PDFNaunyn Schmiedebergs Arch Pharmacol
December 2024
Institute for Pharmacology and Toxicology, Medical Faculty, Martin Luther University Halle-Wittenberg, Magdeburger Straße 4, D-06097, Halle (Saale), Germany.
There is a controversy whether histamine H-receptor activation raises or lowers or does not affect contractility in the human heart. Therefore, we studied stimulation of H-receptors in isolated electrically stimulated (one beat per second) human atrial preparations (HAP). For comparison, we measured force of contraction in left atrial preparations (LA) from mice with overexpression of the histamine H-receptor in the heart (H-TG).
View Article and Find Full Text PDFMetabolites
December 2024
Department of Molecular Biology and Genetics, Lopukhin Federal Research and Clinical Center of Physical-Chemical Medicine of Federal Medical Biological Agency, 119435 Moscow, Russia.
Background: Data on the genetic factors contributing to inter-individual variability in muscle fiber size are limited. Recent research has demonstrated that mice lacking the Arkadia (RNF111) N-terminal-like PKA signaling regulator 2N (; also known as ) gene exhibit reduced muscle fiber size, contraction force, and exercise capacity, along with defects in calcium handling within fast-twitch muscle fibers. However, the role of the gene in human muscle physiology, and particularly in athletic populations, remains poorly understood.
View Article and Find Full Text PDFBiosensors (Basel)
December 2024
Department of Biomedical Engineering, The Hong Kong Polytechnic University, Hong Kong SAR, China.
Ankle-foot orthoses (AFOs) have been commonly prescribed for stroke survivors with foot drop, but their impact on the contractions of paretic tibialis anterior (TA) and medial gastrocnemius (MG) has remained inconclusive. This study thus investigated the effect of AFOs on these muscle contractions in stroke survivors. The contractions of paretic TA and MG muscles were assessed in twenty stroke patients and compared between walking with and without AFOs, using a novel wearable dynamic ultrasound imaging and sensing system.
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