Publications by authors named "Ayrat U Ziganshin"

ATP, being a well-known universal high-energy compound, plays an important role as a signaling molecule and together with its metabolite adenosine they both attenuate the release of acetylcholine in the neuro-muscular synapse acting through membrane P2 and P1 receptors, respectively. In this work, using a mechanomyographic method, we analyzed the presynaptic mechanisms by which ATP and adenosine can modulate the transduction in the rat and . N-ethylmaleimide, a G-protein antagonist, prevents the modulating effects of both ATP and adenosine.

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The purine signaling system is represented by purine and pyrimidine nucleotides and nucleosides that exert their effects through the adenosine, P2X and P2Y receptor families. It is known that, under physiological conditions, P2 receptors play only a minor role in modulating the functions of cells and systems; however, their role significantly increases under some pathophysiological conditions, such as stress, ischemia or hypothermia, when they can play a dominant role as a signaling molecule. The diversity of P2 receptors and their wide distribution in the body make them very attractive as a target for the pharmacological action of drugs with a new mechanism of action.

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A review of the data on the modulatory action of adenosine 5'-triphosphate (ATP), the main co-transmitter with acetylcholine, and adenosine, the final ATP metabolite in the synaptic cleft, on neuromuscular transmission is presented. The effects of these endogenous modulators on pre- and post-synaptic processes are discussed. The contribution of purines to the processes of quantal and non-quantal secretion of acetylcholine into the synaptic cleft, as well as the influence of the postsynaptic effects of ATP and adenosine on the functioning of cholinergic receptors, are evaluated.

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Introduction: The aim of this study was to compare the effects of adenosine-5'-triphosphate (ATP) and adenosine on the contractility of rodent extensor digitorum longus (EDL) muscle at normal and low temperatures.

Methods: Contractions of rat and mouse isolated EDL were induced by either electrical stimulation (ES) or exogenous carbachol and recorded in the presence of ATP or adenosine (both at 100 μM).

Results: ATP at all temperatures caused a decrease of the contractions induced by carbachol in rat and mouse EDL and ES-induced contractions in rat EDL, while it potentiated the ES-induced contractions of mouse EDL.

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Background: The partnership between Yale University (USA) and Kazan State Medical University (KSMU, Russia) was established in 1996 and transitioned to Western Connecticut Health Network (WCHN)/University of Vermont Robert Larner, M.D. College of Medicine (USA) in 2012 with the goal of modernizing medical education at KSMU primarily through introduction of the American medical education structure, role modeling, and educational capacity building.

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Introduction: The aim of this study was to evaluate the effects of adenosine 5'-triphosphate (ATP) and adenosine on the contractility of mammalian skeletal muscle under hypothermic conditions.

Methods: Contractions of isolated rat soleus muscle were induced by either electrical stimulation (ES) or carbachol at physiological temperatures (37°C) and hypothermic conditions (30-14°C) and recorded in the presence of ATP, adenosine, suramin, and 8-(p-sulfophenyl)-theophylline (8-SPT).

Results: At 37°C, incubation of the muscles with ATP inhibited ES-induced contractions; the inhibitory effect of ATP disappeared at 14°C.

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Background: Global health is a new concept in Russia. There has been an ongoing academic collaboration between the Yale School of Medicine in the United States and Makerere University College of Health Sciences in Uganda since 2010, and the US Western Connecticut Health Network/University of Vermont College of Medicine since 2012, to introduce global health concepts to Kazan State Medical University (KSMU) in Russia. The purpose was to educate Russian physicians and medical trainees about the practice of clinical medicine and medical education, as well as the general practice of global health in culturally diverse, resource-limited settings.

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Although the presence of purinoreceptors has been shown in many human and animal arteries, there is few data yet about their role in the arteries of the eye. The purpose of the present study was to evaluate the effects of several agonists of purinoreceptors on isolated arteries of the bovine eye. Responses of isolated preparations of bovine ophthalmic (OA) and posterior ciliary arteries (PCA) to agonists of purinoreceptors (ATP, α,β-methylene-ATP-α,β-meATP, 2-methylthioATP-2meSATP, uridine-5'-triphosphate-UTP) as well as agonists of adreno-, cholino-, adenosine and histamine receptors were recorded by a standard organ bath method.

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