Showing papers in "Physiology in 1989"
TL;DR: The role of the endothelium as a "mechanotransducer" of flow-related forces, particularly shear stresses, is of great interest because flow is known to influence constriction and relaxation of small arteries.
Abstract: Endothelial cells lining the circulation are continuously subjected to hemodynamic forces. Because flow is known to influence constriction and relaxation of small arteries and is implicate...
98 citations
TL;DR: Patch-clamp studies showed that the regulatory volume decrease process is closely associated with functions of K+, Cl-, and Ca2+-permeable channels in epithelial cells, as deduced from whole cell recordings using intestinal epithelial Cells.
Abstract: Patch-clamp studies showed that the regulatory volume decrease process is closely associated with functions of K+, Cl-, and Ca2+-permeable channels in epithelial cells. Na+-permeable channels in the regulatory volume increase process may also be involved, as deduced from whole cell recordings using intestinal epithelial cells.
66 citations
TL;DR: Physiology textbooks almost always include the axon reflex in the context of the triple response, often followed by the caveat that the evidence is either indirect or incomplete.
Abstract: Physiology textbooks almost always include the axon reflex in the context of the triple response, often followed by the caveat that the evidence is either indirect or incomplete. Experimen...
56 citations
TL;DR: Tight Junctions seal the luminal border of epithelial cells and restrict the passage of substances across the paracellular route by exploiting the resistance offered by this pathway.
Abstract: Tight Junctions seal the luminal border of epithelial cells and restrict the passage of substances across the paracellular route. The resistance offered by this pathway is variable and dep...
51 citations
TL;DR: Loss of phospholipids, either by enhanced hydrolysis or by impaired resynthesis, has been proposed as the cause of ischemia- and reperfusion-induced ruptures in the sarcolemma.
Abstract: Loss of phospholipids, either by enhanced hydrolysis or by impaired resynthesis, has been proposed as the cause of ischemia- and reperfusion-induced ruptures in the sarcolemma. Alternatively, if fracture of the sacrolemma were caused by physical forces, enhanced phospholipid degradation would be the epiphenomenon reflecting autolysis of irreversibly damaged cells.
41 citations
TL;DR: Neuropeptide Y enhances the vasomotor effects to noradrenaline and inhibits its release from perivascular nerves, and probably is a cotransmitter in sympathetic vascular control.
Abstract: Neuropeptide Y (NPY) exerts potent vasoconstrictor activity and is coreleased with noradrenaline from sympathetic nerves, mainly on a high degree of activation. It may contribute to the vasoconstriction on high-frequency sympathetic stimulation during control conditions and mediate the long-lasting responses evoked by nerve stimulation in the absence of noradrenaline. NPY enhances the vasomotor effects to noradrenaline and inhibits its release from perivascular nerves. NPY probably is a cotransmitter in sympathetic vascular control.
35 citations
TL;DR: Volume regulatory mechanisms, which evolved in Precambrian life and served to prevent cell lysis when the authors' bacterial and invertebrate ancestors were confronted with hypotonic extracellular milieus, have been preserved in vertebrate cells but with redefined and highly sophisticated physiological functions.
Abstract: Volume regulatory mechanisms, which evolved in Precambrian life and served to prevent cell lysis when our bacterial and invertebrate ancestors were confronted with hypotonic extracellular milieus, have been preserved in vertebrate cells but with redefined and highly sophisticated physiological functions.
27 citations
TL;DR: The concept of "functional specificity" implies that each neuron senses only one factor, but in vitro studies show that a neuron can respond to multiple factors.
Abstract: Homeostatic systems are controlled by hypothalamic neurons that sense endogenous factors, including temperature, osmolality, glucose, and reproductive hormones. The concept of "functional specificity" implies that each neuron senses only one factor, but in vitro studies show that a neuron can respond to multiple factors. This may explain many interactions observed between regulatory systems.
22 citations
TL;DR: In this paper, the authors describe the characteristics of weak ion exchangers and how they are stored in and released from these granules in the form of biogenic amines in cells, chromaffin cells and nerves.
Abstract: Mast cells, chromaffin cells, and nerves contain granule materials that have the characteristics of weak ion exchangers. Biogenic amines are stored in and released from these granules acco...
21 citations
TL;DR: Results of recent investigations on the immunological regulation of gastrointestinal function infer that future considerations of factors that coordinate the physiological behavior of epithelium and smooth muscle must include the role of the mucosal immune system.
Abstract: Results of recent investigations on the immunological regulation of gastrointestinal function infer that future considerations of factors that coordinate the physiological behavior of epithelium and smooth muscle must include the role of the mucosal immune system. Implications of such regulation extend to mucosal tissues beyond the alimentary canal.
21 citations
TL;DR: Endothelial cells regulate production and release of mediators that signal underlying smooth muscle to contract, relax, or proliferate in response to stimuli within the lumen of blood vessels.
Abstract: Endothelial cells are exposed to stimuli within the lumen of blood vessels. Interpreting these signals, endothelial cells regulate production and release of mediators that signal underlying smooth muscle to contract, relax, or proliferate. Specialization of endothelial cells in different vascular beds may determine regional responses.
TL;DR: Arterial baroreceptors effectively buffer short-term pressure changes and appear to be minor in relation to cardiopulmonary reflexes, but their importance for long- term pressure control appears to beMinor.
Abstract: Arterial baroreceptors effectively buffer short-term pressure changes. However, their importance for long-term pressure control appears to be minor. In contrast, cardiopulmonary reflexes c...
TL;DR: Mechanisms that regulate regional vascular resistance and contribute importantly to the overall moment-to-moment regulation of cardiac output and total peripheral resistance are reviewed.
Abstract: The contribution of local autoregulatory mechanisms to the overall control of the systemic circulation has been analyzed using theoretical and experimental approaches. Mechanisms that regu...
TL;DR: Recently developed techniques allow the study of energy flow at the cellular level and show in new detail how cells are individually adapted for their particular energetic roles.
Abstract: Recently developed techniques allow the study of energy flow at the cellular level and show in new detail how cells are individually adapted for their particular energetic roles.
TL;DR: In deciding the number of animals required for an experiment the biologist must achieve a balance between several interacting and competing elements, and recent widespread legislative changes may affect that balance.
Abstract: In deciding the number of animals required for an experiment the biologist must achieve a balance between several interacting and competing elements. Recent widespread legislative changes, directed to a wider scrutiny of this decision process, may affect that balance. The consequences are examined and shown to be potentially detrimental.
TL;DR: ABSTRACT GTP-binding proteins (G or N) transduce signals from various membrane receptors to effector systems in the cell membrane.
Abstract: GTP-binding proteins (G or N) transduce signals from various membrane receptors to effector systems in the cell membrane. Recently it was shown that G proteins couple a variety of receptor...
TL;DR: Do errors in maintenance of the ascorbic acid/dehydro-L-ascorbic acid profile predispose to disease?
Abstract: Ascorbic acid is becoming recognized as an important antioxidant in biology. Do errors in maintenance of the ascorbic acid/dehydro-L-ascorbic acid profile predispose to disease?
TL;DR: The involvement of activity in synapse elimination at the neuromuscular junction is discussed, and a mechanism is proposed based on the molecular processes that are a consequence of normal neuromUScular activity.
Abstract: The involvement of activity in synapse elimination at the neuromuscular junction is discussed, and a mechanism is proposed based on the molecular processes that are a consequence of normal neuromuscular activity.
TL;DR: The recently identified existence of a dorsolateral spinothalamic tract of unknown function calls for revision of a classic tenet of pain transmission.
Abstract: The recently identified existence of a dorsolateral spinothalamic tract of unknown function calls for revision of a classic tenet of pain transmission. Moreover, the newly described direct...
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TL;DR: The main approaches to the study of mankind, and the corresponding models of man, are sketched and examined in this article, where the systemic model of man as a biopsychosocial entity is recommended.
Abstract: The main approaches to the study of mankind, and the corresponding models of man, are sketched and examined. The systemic model of man as a biopsychosocial entity is recommended. Likewise ...
TL;DR: Autoregulation of release, mediated by presynaptic autoreceptors, is triggered by endogenous transmitter, is followed by modulation of transmission to postsynaptic cells, and operates in vivo.
Abstract: Axon terminals are both transmissive and receptive structures. Their own transmitter is one of the chemical signals they receive and translate into a modulation of release. Autoregulation of release, mediated by presynaptic autoreceptors, is triggered by endogenous transmitter, is followed by modulation of transmission to postsynaptic cells, and operates in vivo.
TL;DR: Exocytosis is controlled by guanine nucleotide-binding proteins acting as key signal transducers and different G proteins mediate receptor signaling and secretory granule-membrane fusion.
Abstract: Exocytosis can be quantified by measuring changes in membrane capacitance in single internally perfused cells. Exocytosis is controlled by guanine nucleotide-binding proteins (G proteins) acting as key signal transducers. Different G proteins mediate receptor signaling and secretory granule-membrane fusion.
TL;DR: The endothelium of these capillaries acts as blood-brain barrier, with a high electrical resistance and specific carrier systems, in mice derived extraneurally from the vasculature of the brain.
Abstract: The vasculature of the brain is derived extraneurally. The endothelium of these capillaries acts as blood-brain barrier, with a high electrical resistance and specific carrier systems. The...
TL;DR: Nephrotoxicity, produced by aminoglycoside antibiotics, is now being studied in a useful model of cultured renal cells and the cellular characteristics of nephrotoxicity could provide new insights into an important clinical problem by disclosing the transport mechanisms of aminglycoside into the proximal tubular cells.
Abstract: Nephrotoxicity, produced by aminoglycoside antibiotics, is now being studied in a useful model of cultured renal cells. These studies could provide new insights into an important clinical ...
TL;DR: The mechanism by which a change in smooth muscle phenotype is effected in the artery wall during atherogenesis may be via release of extracellular matrix-degrading enzymes, particularly heparanase, from activated macrophages and T lymphocytes.
Abstract: The mechanism by which a change in smooth muscle phenotype is effected in the artery wall during atherogenesis may be via release of extracellular matrix-degrading enzymes, particularly heparanase, from activated macrophages and T lymphocytes.
TL;DR: Amplification between, rather than individual potencies of, agonists determines their importance during hemostasis or thrombus formation, which explains why serotonin is an important vector in platelet-vessel wall interactions.
Abstract: Platelets react to aggregate or adhere with different intensities depending on the nature of the challenge. Amplification between, rather than individual potencies of, agonists determines their importance during hemostasis or thrombus formation. Such amplification explains why serotonin is an important vector in platelet-vessel wall interactions.
TL;DR: Catecholamines are essential hormones for exercise and may be altered by exercise training, which may affect exercise-relatedabolism and secretion of catecholamine.
Abstract: Catecholamines are essential hormones for exercise. Metabolism and secretion of catecholamines may be altered by exercise training. Vasoregulation may also be affected by neuropeptides (VI...
TL;DR: The gain of the monosynaptic stretch rerflex is controlled by many spinal pathways and only human experiments allow the exploration of changes in transmission in these pathways during voluntary movement.
Abstract: The gain of the monosynaptic stretch rerflex is controlled by many spinal pathways. Only human experiments allow the exploration of changes in transmission in these pathways during voluntary movement. Unexpected results have been obtained, which have led to new conceptions concerning the functional role of the spinal circuitry.
TL;DR: Mammals acutely exposed to hypobaric hypoxia establish a lower plasma volume by increasing urine excretion or by reducing salt and water intake, for by concentrating available hemoglobin they increase OS-binding capacity of the blood.
Abstract: Mammals acutely exposed to hypobaric hypoxia establish a lower plasma volume by increasing urine excretion or by reducing salt and water intake. These responses are of adaptive value, for by concentrating available hemoglobin they increase OS-binding capacity of the blood. The reactions of sodium metabolism in arterial hypoxia are controlled by peripheral arterial chemoreceptors.
TL;DR: A large number of cell types have a signalling role for cytoplasmic free Ca, and the past decade has seen an explosion in understanding the role played by inositol polysaccharide in these cells.
Abstract: For many cell types a signalling role for cytoplasmic free Ca was established over 10 years ago, and the past decade has seen an explosion in understanding the role played by inositol poly...