Ceskoslovenska fysiologie最新文献

Efforts were already made in antiquity to understand the structure and function of the brain and nervous tissue, but an important impulse for the development of neuroanatomy as a field was the invention of the microscope at the beginning of the 17th century. A brief overview of the history of research of the brain and nerve structure from Marcello Malpighi to Christian Berres shows by what small steps and with what difficulties the investigation of the composition of the nervous tissue advanced. The study of historical sources reveals that despite constantly improving microscopic techniques, many prominent researchers obtained inaccurate data and, on the basis of such data, often reached erroneous conclusions. However, these observations and their interpretation and, in addition, the clashing opinions of scholars of that period greatly influenced the work of later researchers in the field of the microscopic structure and function of the nervous tissue.

The orphan nuclear receptors belong to the family of ligand-activated transcription factors localized in the nucleus or cytoplasm. Through them, many biological processes such as metabolism of glucose, lipids and bile acids, inflammation, tumour growth, or differentiation of cells, are controlled. From the pharmacological point of view, they play a significant role in regulating the elimination of xenobiotics from the organism. Also interesting is the possibility of xenobiotic targeting the orphan nuclear receptors for the treatment of metabolic disorders.

Myocardial contractility is the ability of the cardiac muscle to contract, thereby generating force. Contractile functions of the myocardium are influenced by a number of intrinsic and extrinsic factors. The intrinsic factors, including the initial length of the muscle fibers, stimulation frequency and cardiac rhythm are modulated by neurohumoral mechanisms and extrinsic factors (ions and energy balance, temperature, pH, drugs, etc.). The mechanism of the cardiac contraction, intrinsic and neurohumonal regulation of the cardiac activity and changes in contractile functions of the myocardium and their regulation under pathological conditions are described in this article.

Subarachnoid hemorrhage (SAH) of CNS is acute life-threating condition. In addition to its well understood sequential increase in intracranial pressure and decreased cerebral perfusion pressure, there is also early and late vasoconstriction. Mechanism of vasoconstriction is complex and one of important roles play changes in the amount of nitric oxide (NO). Present work overviews known pathogenesis of non-traumatic SAH, with stress on NO regulation of cerebral blood flow and its changes during SAH. It also describes mechanisms of early and late brain damage following subarachnoid hemorrhage. We discuss possible pharmacological prevention of the damage and laboratory models of nontraumatic SAH.

Peptide urotensin II was originally isolated from the urophysis of teleost fishes; later it was identified also in higher vertebrates in various organs and tissues, including cardiovascular structures. Since its discovery it has been considered as a highly potent vasoconstrictor inducing contraction of smooth muscle in subnanomolar concentrations. Its wide distribution as well as its high interspecies homology indicates that this peptide is involved in regulation of many important physiological functions in vertebrates. An effort to discover other possible functions of urotensin II was intensified by the identification of its G-protein coupled receptor and its identification in humans. Furthermore, altered levels of expression of urotensin II and its receptor were found in various disease states including hypertension, diabetes, heart and renal failure, in experimental animal models as well as in humans. Therefore, there is widely discussed question regarding the possible role of urotensin II in etiopathogeneses of these diseases, however the exact mechanisms are still unknown. The aim of this review is to summarize the current knowledge about urotensin II with emphasis to its direct and undirect effects in cardiovascular system.

Histamine intolerance (HIT) is a pathological process that results from a disbalance between levels of released histamine and the ability of the body to metabolize it. Accumulated histamine leads to the onset of "histamine mediated" reactions which are usually excessive and decrease quality of life. Although we have a lot of knowledge about histamine intolerance, HIT is still vastly underestimated, because it manifests via the diversity of clinical symptoms, that are often misinterpreted by the patient and sometimes even by a physician. Clinical symptoms and their provocation by certain kinds of food, beverages and drugs are often attributed to the different diseases, such as food allergy and intolerance of sulfites, or other biogenic amines (eg. tyramine), mastocytosis, psychosomatic diseases or adverse drug reactions in general. Proper diagnosis of HIT followed by therapy based on histamine--free diet and supplementation of diaminooxidase can considerably improve patient's quality of life.

Purinergic P2X receptors (P2XR), activated by extracellular adenosine 5'-triphosphate (ATP), represent a specific type of ligand-gated ion channels. They form functional trimeric homomers or heteromers which are nonselectively cation-permeable after receptor activation. P2X receptors are widely expressed in excitable and nonexcitable tissues and are involved in many physiological and pathophysiological processes such as platelet aggregation, contraction of smooth muscle, immune responses, cell proliferation and apoptosis or neurotransmission. In mammals, seven P2X subunits (P2X1-P2X7) have been identified. They differ mainly in distribution, pharmacological profile and kinetics of ATP-induced responses. The subtype P2X7 is the most specific in the P2X family and widely differs from other P2X subtypes.

The Czech anatomist and physiologist of the 18th century, Jirí Procháska (1749-1820), ranks among the major figures of Czech cultural history. Due to historical circumstances, the works of Jirí Procháska were published mostly in Latin and only some in German. However, given that only two of his works have been translated into Czech and one of them also partially into English, the results of his extensive research activities are currently unavailable not only to the international scientific community, but also to the Czech scientific community. Although his research reflected the time in which he lived and thus has been re-evaluated by later researchers, his achievements undoubtedly belong to the major intellectual heritage of Czech science and certainly deserve attention as such. It is therefore our duty not only to remember the work and legacy of Jirí Procháska, which significantly influenced the development of our knowledge, but also to try to critically assess his contribution in terms of today. The article surveys the important biographical events of Jirí Procháska's life, taking into account the importance of his research and teaching.