: 1. Centrally acting imidazoline antihypertensive agents clonidine and moxonidine also act peripherally to contract blood vessels. While these agents act at both I(1)-imidazoline and alpha 2 adrenergic receptors centrally, the receptor types by which they mediate contraction require further definition. We therefore characterized the receptor subtype by which these agents mediate contraction of proximal rat-tail artery. 2. Dose-response curves were determined for phenylephrine and for several imidazoline ligands, using endothelium denuded, isolated ring segments, of tail arteries from adult male Sprague-Dawley rats. Ring segments were mounted on a force transducer with platinum wires and immersed in a tissue bath containing Krebs solution, to which drugs could be added. Signals were digitized and recorded by a computer. 3. Tail artery contractions expressed as a percent of contraction to 106 mM potassium were phenylephrine (96%), moxonidine (88%), clonidine (52%), and UK14304 (30%). Neither rilmenidine nor harmane caused contraction. Contraction of tail artery to moxonidine or clonidine could be blocked by alpha 1 antagonist urapidil or prazosin, and also by alpha 1A subtype selective antagonist WB4101. Schild plots were generated and a calculated pA2 value of 9.2 for prazosin in the presence of clonidine confirms clonidine as an agonist at alpha 1A receptors in proximal segments of rat-tail artery. 4. Our work suggests that clonidine and moxonidine are promiscuous compounds at micromolar concentrations and that harmane and rilmenidine are more selective compounds for in vivo imidazoline research.
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http://dx.doi.org/10.1007/s10571-006-9109-x | DOI Listing |
J Toxicol Environ Health A
March 2025
Physical Effects Research Branch, National Institute for Occupational Safety and Health, Morgantown, WV, USA.
Workers regularly using vibrating hand tools may develop a disorder referred to as hand-arm vibration syndrome (HAVS). HAVS is characterized by cold-induced vasospasms in the hands and fingers that result in blanching of the skin, loss of sensory function, pain, and reductions in manual dexterity. Exposure to vibration induces some of these symptoms.
View Article and Find Full Text PDFInt J Biol Macromol
November 2024
School of Chemistry, Xi'an Key Laboratory of Sustainable Energy Material Chemistry, Xi'an Jiaotong University, Xi'an 710049, PR China; The First Affiliated Hospital, Xi'an Jiaotong University, Xi'an 710061, PR China; Instrumental Analysis Center of Xi'an Jiaotong University, Xi'an 710049, PR China. Electronic address:
Developing porous hemostatic sponges that are both biosafe and multifunctional remains a complex challenge. Conventional hemostatic techniques often fall short in managing bleeding effectively, leading to severe critical cases such as suboptimal hemostasis, increased infection risk, and complications arising from profuse bleeding. To address these deficits, our study introduces a novel multifunctional nanocomposite sponge that synergistically incorporates chitosan (CS), cellulose (Cel), graphene oxide (GO), and silver (Ag) nanoparticles.
View Article and Find Full Text PDFInt J Mol Sci
June 2024
Physiology, Institute of Theoretical Medicine, Faculty of Medicine, University of Augsburg, 86159 Augsburg, Germany.
It has been reported that, in the spontaneously hypertensive rat (SHR) model of hypertension, different components of the G-protein/adenylate cyclase (AC)/Calcium-activated potassium channel of high conductance (BK) channel signaling pathway are altered differently. In the upstream part of the pathway (G-protein/AC), a comparatively low efficacy has been established, whereas downstream BK currents seem to be increased. Thus, the overall performance of this signaling pathway in SHR is elusive.
View Article and Find Full Text PDFJ Colloid Interface Sci
November 2024
Department of Orthopaedics, Xinqiao Hospital, Army Medical University, No. 183, Xinqiao Street, Shapingba District, Chongqing 400037, China. Electronic address:
Multifunctional bioactive biomaterials with integrated bone and soft tissue regenerability hold great promise for the regeneration of trauma-affected skin and bone defects. The aim of this research was to fabricate aerogel scaffolds (GD-BF) by blending the appropriate proportions of short bioactive glass fiber (BGF), gelatin (Gel), and dopamine (DA). Electrospun polyvinyl pyrrolidone (PVP)-BGF fibers were converted into short BGF through calcination and homogenization.
View Article and Find Full Text PDFVascular
May 2024
Department of Vascular Surgery, The First Affiliated Hospital of Wannan Medical College, Wuhu, P.R. China.
Objective: To investigate the safety and efficacy of endovascular treatment for totally occlusive lesions of the subclavian artery (SCA).
Methods: A retrospective study was performed on 57 patients treated with angioplasty and stenting, including 42 males and 15 females, with an average age of 61.8 years (range: 49 to 81 years).
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