Neuron generator potentials evoked by intracellular injection of cyclic nucleotides and mechanical distension

Liberman, E. A.; Minina, S.V.; Mjakotina, O.L.; Shklovsky-Kordy, N.E.; Conrad, Michael

doi:10.1016/0006-8993(85)90245-8

Cited by 50 publications

(6 citation statements)

References 23 publications

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“…Since in K-free solution an increase of intracellular level of cAMP took place [Ayrapetyan et al, 1992], which had stimulating effect on pacemaker activity of cells [Adams and Levitan, 1982;Liberman and Minias, 1985], it could be predicted that K-free MPS could stimulate the pacemaker activity of heart by elevation of intracellular level of cAMP. However, the data on depressing effect of MPS on intracellular level of cAMP (Table 1) fully excludes this speculation.…”

Section: Discussionmentioning

confidence: 99%

Metabolic pathway of magnetized fluid‐induced relaxation effects on heart muscle

Ayrapetyan¹,

Papanyan²,

Hayrapetyan³

et al. 2005

Bioelectromagnetics

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The effect of magnetized physiological solution (MPS) on isolated, perfused snail heart muscle contractility, (45)Ca uptake and intracellular level of cAMP, and cGMP was studied. The existence of the relaxing effect of MPS on heart muscle at room temperature (22 degrees C) and its absence in cold medium (4 degrees C) was shown. The MPS had a depressing effect on (45)Ca uptake by muscles and intracellular cAMP content and an elevating effect on intracellular cGMP level. It is suggested that the relaxing effect of MPS on heart muscle is due to the decrease of intracellular Ca ions as the result of activation of cGMP-dependent Ca efflux. The MPS induced decrease of intracellular cAMP content can be considered as a consequence of intracellular Ca loss, leading to the Na + K-ATPase reactivation, and causing the decrease of the intracellular level of ATP, serving as a substrate and positive modulator of cyclase activity.

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Section: Discussionmentioning

confidence: 99%

Metabolic pathway of magnetized fluid‐induced relaxation effects on heart muscle

Ayrapetyan¹,

Papanyan²,

Hayrapetyan³

et al. 2005

Bioelectromagnetics

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“…Agents that either elevate the intracellular concentration of adenosine 3',5'-cyclic monophosphate (CAMP) or mimic its effects have been shown to induce excitatory responses in certain types of invertebrate and vertebrate neurons (Connor and Hockberger, 1984;Kaczmarek and Strumwasser, 1981;Kononenko et al, 1983;Liberman et al, 1985;Madison and Nicoll, 1986;Palmer et al, 1986;Siggins, 1982;Treistman and Drake, 1979). These effects of CAMP are associated with changes in various ionic conductances, including an increase in the influx of Na or Ca ions (Aldenhoff et al, 1983;Connor and Hockberger, 1984;Green and Gillette, 1983;Hara et al, 1985;Liberman et al, 1985;Pellmar, 1981;Swandulla and Lux, 1984), a reduction in early and delayed K currents (Kaczmarek and Strumwasser, 1984;Strong, 1984;Strong and Kaczmarek, 19861, a depression of the Ca-activated K current Madison and Nicoll, 19861, and a closing of another type of K channel, the S channel (Deterre et al, 1982;Siegelbaum et al, 1982). In a previous report, the incidental observation was made that the firing rate of noradrenergic neurons of the locus coeruleus (LC) in brain slices is increased by 8-bromo-cAMP (8-Br-CAMP) (Andrade and Aghajanian, 19851, a membrane permeable analog of CAMP.…”

Section: Introductionmentioning

confidence: 99%

Excitation of locus coeruleus neurons by an adenoine 3′,5′‐cyclic monophosphate‐activated inward current: Extracellular and intracellular studies in rat brain slices

Wang

Aghajanian

1987

Synapse

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The firing rate of locus coeruleus (LC) neurons in rat brain slices was increased reversibly by agents that either elevate intracellular levels of adenosine 3',5'-cyclic monophosphate (cAMP) or mimic its actions (e.g., forskolin, and activator of adenylate cyclase, 8-Br-cAMP, a membrane permeable analog of cAMP, and Ro20-1724, a preferential inhibitor of cAMP-phosphodiesterase). Intracellular recordings showed that 8-Br-cAMP and forskolin induce a depolarization of LC neurons, accompanied by a decrease in input resistance. The 8-Br-cAMP- and forskolin-elicited depolarization persisted in the presence of cobalt, a calcium channel blocker. Steady-state current-voltage curves revealed that in the voltage range of -50 to -120 mV, 8-Br-cAMP and forskolin induced an inward current, which did not reverse at the potassium equilibrium potential and could not be blocked by tetrodotoxin. Partial replacement of sodium with Tris or choline markedly reduced the depolarization elicited by 8-Br-cAMP. We conclude that 8-Br-cAMP and forskolin act through a common mechanism to increase the firing rate of locus coeruleus neurons by inducing a cAMP-activated inward current, carried out at least in part by sodium ions.

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“…The enzymatic neurons take the more specific form of cytoskeletal neurons in ANM system. The assumption is that the transduction of input patterns into activity patterns is mediated by the membrane cytoskeleton, a fibrous network that strongly influences the shape and motion of cells (Matsumoto 1979;Liberman et al 1982Liberman et al ,1985Conrad 1990a;Hameroff et al 1992;Werbos 1992).…”

Section: Perpetual Evolutionmentioning

confidence: 99%

Evolutionary learning with a neuromolecular architecture: a biologically motivated approach to computational adaptability

Chen

Conrad

1997

Soft Computing - A Fusion of Foundations, Methodologies and App

Self Cite

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The effectiveness of evolutionary learning depends both on the variation-selection search operations used and on the structure-function relations of the organization to which these operations are applied. Some organizations-in particular those that occur in biology-are more evolution friendly than others. We describe an artificial neuromolecular (ANM) architecture that illustrates the structure-function relationships that underlie evolutionary adaptability and the manner in which these relationships can be represented in computer programs. The ANM system, a brain-like design that combines intraand interneuronal levels of processing, can be coupled to a variety of pattern recognition-effector control tasks. The capabilities of the model, in particular its adaptability properties, are here illustrated in the context of Chinese character recognition. IntroductionBiological information processing provides a paradigm for soft computing. We have developed an artificial neuromolecular (ANM) architecture that illustrates the general motivations for this approach and the representational problems that arise. The purpose of the present paper is to describe this brain-like architecture in some detail and to describe recent results obained with it in the domain of Chinese character recognition. We will be particularly concerned with the problem of achieving computational adaptability through means of evolutionary learning.The basic goal of the biologically motivated approach is to provide the digital machine with a representation of the internal structure-function relations of biological systems, to capture some of the dynamic modes of processing of these systems, and to incorporate learning algorithms of the type used in natural systems. The approach is in a sense complementary to that of classical artificial intelligence, where the goal can in many cases be thought of in terms of providing the machine with a representation of the external world.Biological systems implement biological modes of processing much more naturally than digital machines. The structurefunction relations are clearly very different, since digital machines are designed to be effectively programmable, whereas self-organizing dynamics are the essence of biological processing. The biologically motivated approach therefore encompasses the attempt to build actual hardware (or better, molecularware) that is natural to the biological mode of processing (Conrad 1995). Here, however, our concern is with using the digital machine to capture aspects of the biological mode to the extent permitted by the inherent computational differences between present day machines and organisms. The ANM architecture is therefore a virtual architecture. We can regard it on the one hand as a tool for examining the nature of biological processing itself, and on the other as a tool that is capable of yielding practical benefits.

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Neuron generator potentials evoked by intracellular injection of cyclic nucleotides and mechanical distension

Cited by 50 publications

References 23 publications

Metabolic pathway of magnetized fluid‐induced relaxation effects on heart muscle

Metabolic pathway of magnetized fluid‐induced relaxation effects on heart muscle

Excitation of locus coeruleus neurons by an adenoine 3′,5′‐cyclic monophosphate‐activated inward current: Extracellular and intracellular studies in rat brain slices

Evolutionary learning with a neuromolecular architecture: a biologically motivated approach to computational adaptability

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