Kv2.2, homologous to the shab family of Drosophila voltage-gated K+ channels, was isolated from human and canine colonic circular smooth muscle-derived mRNA. Northern hybridization analysis performed on RNA prepared from tissues and RT-PCR performed on RNA isolated from dispersed and selected smooth muscle cells demonstrate that Kv2.2 is expressed in smooth muscle cells found in all regions of the canine gastrointestinal (GI) tract and in several vascular tissues. Injection of Kv2.2 mRNA into Xenopus oocytes resulted in the expression of a slowly activating K+ current (time to half maximum current, 97 +/- 8.6 ms) mediated by 15 pS (symmetrical K+) single channels. The current was inhibited by tetraethylammonium (IC50 = 2.6 mM), 4-aminopyridine (IC50 = 1.5 mM at +20 mV), and quinine (IC50 = 13.7 microM) and was insensitive to charybdotoxin. Low concentrations of quinine (1 microM) were used to preferentially block the slow component of the delayed rectifier current in native colonic myocytes. These data suggest that Kv2.2 may contribute to this current in native GI smooth muscle cells.
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http://dx.doi.org/10.1152/ajpgi.1998.274.5.G901 | DOI Listing |
ACS Biomater Sci Eng
January 2025
Department of Biomedical Engineering, Southern University of Science and Technology, Shenzhen, Guangdong 518055, P.R. China.
Vascular calcification severely disrupts cardiovascular hemodynamics, leading to high rates of morbidity and mortality. Despite their clinical impact, the development of effective treatments remains limited, underscoring an urgent need for efficient and reliable drug screening methods. Vascular smooth muscle cells (VSMCs) are known to play a central role in driving the calcification process, undergoing an osteogenic transition in response to pathological conditions.
View Article and Find Full Text PDFWorld J Biol Psychiatry
January 2025
Division of Genetics, Department of Cell and Molecular Biology and Microbiology, Faculty of Biological Science and Technology, University of Isfahan, Isfahan, Iran.
Background: Genes associated with global developmental delay (GDD) and intellectual disability (ID) are increasingly being identified through next-generation sequencing (NGS) technologies. This study aimed to identify novel mutations in GDD/ID phenotypes through whole-exome sequencing (WES) and additional analyses.
Material And Methods: WES was performed on 27 subjects, among whom 18 were screened for potential novel mutations.
Vet Sci
January 2025
Department of Veterinary Medicine, University of Perugia, Via San Costanzo 4, 06126 Perugia, Italy.
Ghrelin (GhRL) is an orexigenic hormone influenced by nutritional state. It plays a role in skin repair and diseases, though little information exists regarding its function in this organ. GhRL and its receptor were investigated in the skin of sheep under different feeding conditions to explore GhRL system presence and possible modifications due to diet.
View Article and Find Full Text PDFMetabolites
January 2025
The College of Nursing, Zhejiang Chinese Medical University, Hangzhou 310053, China.
Background: Postoperative ileus (POI) is a common postoperative clinical complication that significantly affects postoperative rehabilitation and quality of life in patients and can even produce secondary complications, leading to serious consequences. External treatment using Shenhuang Plaster (SHP) (Shenque acupoint administration) has definite effects and unique advantages in the prevention and treatment of POI, but its mechanism is not completely clear. In this study, we investigated the therapeutic mechanism behind the effect of Shenhuang Plaster applied to the Shenque acupoint on gastrointestinal motility in POI mice based on metabolomics.
View Article and Find Full Text PDFBiomimetics (Basel)
January 2025
School of Engineering, University of Kent, Canterbury CT2 7NZ, UK.
Pneumatic artificial muscles (PAMs) are flexible actuators that can be contracted or expanded by applying air pressure. They are used in robotics, prosthetics, and other applications requiring flexible and compliant actuation. PAMs are basically designed to mimic the function of biological muscles, providing a high force-to-weight ratio and smooth, lifelike movement.
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