Physiological implications of the regulation of vacuolar
... In rat cortical late distal tubules, microperfusion experiments have shown that the rate of proton secretion by H+ATPase was also dependent on chloride transport, since the inhibition of Cl- channels by 5-nitro-2-(3-phenylpropylamino)-benzoic acid (NPPB) markedly reduced distal tubule acidification, ...
... In rat cortical late distal tubules, microperfusion experiments have shown that the rate of proton secretion by H+ATPase was also dependent on chloride transport, since the inhibition of Cl- channels by 5-nitro-2-(3-phenylpropylamino)-benzoic acid (NPPB) markedly reduced distal tubule acidification, ...
Print - Circulation
... Low concentrations of ryanodine open the SR calcium release channel and thus deplete the SR calcium stores. This effect has been used to examine the extent to which calcium release from SR by the calciuminduced calcium release mechanism is involved in cardiac E-C coupling. The magnitude of the decre ...
... Low concentrations of ryanodine open the SR calcium release channel and thus deplete the SR calcium stores. This effect has been used to examine the extent to which calcium release from SR by the calciuminduced calcium release mechanism is involved in cardiac E-C coupling. The magnitude of the decre ...
effect of ion concentration changes in t
... Fig.2: Action potentials (Vm ), selected membrane currents (ICa , IKto , IK1 ) and ion concentrations in the 1st , 3rd , 5th , 7th and 9th segment of tubular lumen ([Ca2+ ]t , [K+ ]t ) at 1 Hz and 2.5 Hz steady-state stimulation. The continuous and dotted lines refer to t-tubular and surface membran ...
... Fig.2: Action potentials (Vm ), selected membrane currents (ICa , IKto , IK1 ) and ion concentrations in the 1st , 3rd , 5th , 7th and 9th segment of tubular lumen ([Ca2+ ]t , [K+ ]t ) at 1 Hz and 2.5 Hz steady-state stimulation. The continuous and dotted lines refer to t-tubular and surface membran ...
TESIS DOCTORAL Dynamics and Synchronization in Neuronal Models
... de Puebla, Mexico, we experimentally corroborate the numerical results demonstrating that stochastic resonance phenomenon is also presented in the motor system. In chapter 3 we model the propagation of signals through the spinal cord during a motor activity. Based on previous studies, we propose a n ...
... de Puebla, Mexico, we experimentally corroborate the numerical results demonstrating that stochastic resonance phenomenon is also presented in the motor system. In chapter 3 we model the propagation of signals through the spinal cord during a motor activity. Based on previous studies, we propose a n ...
Muscular System
... Smooth muscle contractions aid in the movement of food through the GI tract, urine through urinary system. Skeletal muscle (squeezing upon contraction) helps return venous blood and lymph to the heart. 3. Maintain body posture and sphincter control. Examples: Skeletal muscle (antagonistic) contract ...
... Smooth muscle contractions aid in the movement of food through the GI tract, urine through urinary system. Skeletal muscle (squeezing upon contraction) helps return venous blood and lymph to the heart. 3. Maintain body posture and sphincter control. Examples: Skeletal muscle (antagonistic) contract ...
The Plasma Membrane of the Cyanobacterium
... The appearance of eukaryotic cells is largely linked to the acquisition of cellular organelles specialized in providing energy and reducing equivalents. The establishment of chloroplasts as permanent endosymbionts constitutes a key event in the evolution of plant cells. In the chloroplast, thylakoid ...
... The appearance of eukaryotic cells is largely linked to the acquisition of cellular organelles specialized in providing energy and reducing equivalents. The establishment of chloroplasts as permanent endosymbionts constitutes a key event in the evolution of plant cells. In the chloroplast, thylakoid ...
The Plasma Membrane of the Cyanobacterium
... The appearance of eukaryotic cells is largely linked to the acquisition of cellular organelles specialized in providing energy and reducing equivalents. The establishment of chloroplasts as permanent endosymbionts constitutes a key event in the evolution of plant cells. In the chloroplast, thylakoid ...
... The appearance of eukaryotic cells is largely linked to the acquisition of cellular organelles specialized in providing energy and reducing equivalents. The establishment of chloroplasts as permanent endosymbionts constitutes a key event in the evolution of plant cells. In the chloroplast, thylakoid ...
Long-Term Maintenance of Channel Distribution in a Central Pattern
... In addition to short-term adaptive influences, modulatory inputs play an important role in longer-term processes, such as the development of neural networks (Sillar et al., 1992, 1995; Fénelon et al., 1998b; Le Feuvre et al., 1999). Synaptic inputs likewise exert long-term control over their target ...
... In addition to short-term adaptive influences, modulatory inputs play an important role in longer-term processes, such as the development of neural networks (Sillar et al., 1992, 1995; Fénelon et al., 1998b; Le Feuvre et al., 1999). Synaptic inputs likewise exert long-term control over their target ...
Multiple Cell Types Distinguished by Physiological
... a local supplier or were bred in our colony at the University of Pennsylvania. Animals were housed three or four per cage in a room on a 13:11 h, light:dark cycle. It is likely that they were in breeding condition and singing before slicing, but their behavioral state was not systematically verified ...
... a local supplier or were bred in our colony at the University of Pennsylvania. Animals were housed three or four per cage in a room on a 13:11 h, light:dark cycle. It is likely that they were in breeding condition and singing before slicing, but their behavioral state was not systematically verified ...
by Booij (Leyden). Introductory § i. systems § 2
... between the particles in a given coacervate particles, having lost part of their water-shell, ...
... between the particles in a given coacervate particles, having lost part of their water-shell, ...
Modulation of Calcium Channel Function in Nerve Cell Membrane
... on data about the functional role of cyclic nucleotide metabolism in activation of protein phosphorylation (e.g. Greengard 1978), it was suggested that the catecholamine-induced potentiation of the calcium component of the cardiac action potential is mediated by increased synthesis of cyclic AMP by ...
... on data about the functional role of cyclic nucleotide metabolism in activation of protein phosphorylation (e.g. Greengard 1978), it was suggested that the catecholamine-induced potentiation of the calcium component of the cardiac action potential is mediated by increased synthesis of cyclic AMP by ...
Ionic Mechanisms in the Generation of Subthreshold Oscillations and
... role of Ih in contributing to the medium hyperpolarization (mAHP) and rebound spiking was studied. The role of Ih and the slow calcium-activated potassium current IK(AHP) in action potential clustering was also studied. Representations of Ih and INaP were developed with parameters based on voltage-c ...
... role of Ih in contributing to the medium hyperpolarization (mAHP) and rebound spiking was studied. The role of Ih and the slow calcium-activated potassium current IK(AHP) in action potential clustering was also studied. Representations of Ih and INaP were developed with parameters based on voltage-c ...
Impact of correlated inputs to neurons
... Input correlations have been observed in membrane potentials recorded from neurons in various brain regions. At the single neuron level, the existence of “activity bumps” (that is, large fluctuations) in the membrane potential trace indicates the arrival of coordinated inputs within a narrow time wi ...
... Input correlations have been observed in membrane potentials recorded from neurons in various brain regions. At the single neuron level, the existence of “activity bumps” (that is, large fluctuations) in the membrane potential trace indicates the arrival of coordinated inputs within a narrow time wi ...
neural_networks
... Pre-synaptic nerve terminal has docked vesicles docked at Membrane containing neurotransmitter Arriving action potential produces influx of calcium ions through voltage-dependent, calcium-selective ion channels. Calcium ions trigger biochemical cascade: vesicles fuse with presynaptic membrane and re ...
... Pre-synaptic nerve terminal has docked vesicles docked at Membrane containing neurotransmitter Arriving action potential produces influx of calcium ions through voltage-dependent, calcium-selective ion channels. Calcium ions trigger biochemical cascade: vesicles fuse with presynaptic membrane and re ...
Cutaneous Sensory Neurons Expressing the Mrgprd Receptor
... Patch-clamp electrophysiology was performed on DRG neurons in culture from adult knock-in mice in which GFP is expressed under the control of endogenous Mrgprd regulatory elements. Expression of GFP was used as a marker for cells that contain the Mrgprd receptor (see METHODS). Several cultures were ...
... Patch-clamp electrophysiology was performed on DRG neurons in culture from adult knock-in mice in which GFP is expressed under the control of endogenous Mrgprd regulatory elements. Expression of GFP was used as a marker for cells that contain the Mrgprd receptor (see METHODS). Several cultures were ...
Thalamocortical inputs trigger a propagating envelope of gamma
... MG (MGv) and delineates the extent of their terminal arbors in the middle layers of primary auditory cortex (Robertson et al. 1991). In 15 juvenile rats, slices cut as described to maintain the thalamocortical pathway displayed distinct AChE-positive bands in auditory cortex (Fig. 1B) as well as den ...
... MG (MGv) and delineates the extent of their terminal arbors in the middle layers of primary auditory cortex (Robertson et al. 1991). In 15 juvenile rats, slices cut as described to maintain the thalamocortical pathway displayed distinct AChE-positive bands in auditory cortex (Fig. 1B) as well as den ...
Article Full Text PDF
... performed with microelectrodes. The resting potential was ,280 mV with an input resistance of ,0.42 MV. The M-cell extracellular field was large (10-20 mV), close to the axon hillock, and the latency of antidromic spikes short (,0.4 milliseconds), confirming a high conduction velocity in the M-axon. ...
... performed with microelectrodes. The resting potential was ,280 mV with an input resistance of ,0.42 MV. The M-cell extracellular field was large (10-20 mV), close to the axon hillock, and the latency of antidromic spikes short (,0.4 milliseconds), confirming a high conduction velocity in the M-axon. ...
Why Ca2+ is chosen by nature for diverse regulations?
... Protein Kinase C Phospholipase A2 Prothrombin Calpain DNAse 1 ...
... Protein Kinase C Phospholipase A2 Prothrombin Calpain DNAse 1 ...
physiological reviews
... The perilymphatic space communicates with the cerebrospinal space by the cochlear aqueduct and by perineural and perivascular spaces in the internal auditory meatus. In the guinea pig, cerebrospinal fluid certainly can enter by these channels when an artificial opening is made into the cochlea. Red ...
... The perilymphatic space communicates with the cerebrospinal space by the cochlear aqueduct and by perineural and perivascular spaces in the internal auditory meatus. In the guinea pig, cerebrospinal fluid certainly can enter by these channels when an artificial opening is made into the cochlea. Red ...
Distinct Roles of CaMKII and PKA in Regulation of Firing Patterns
... step current injections (80 –120 pA) at 0.5 Hz or lower to minimize the interaction between successive pulses, wild-type neurons displayed highly reproducible firing patterns in response to these identical repeated stimuli (Fig. 5A). The firing pattern, in particular the number of spikes in each spi ...
... step current injections (80 –120 pA) at 0.5 Hz or lower to minimize the interaction between successive pulses, wild-type neurons displayed highly reproducible firing patterns in response to these identical repeated stimuli (Fig. 5A). The firing pattern, in particular the number of spikes in each spi ...
Molecular Underpinnings of Motor Pattern Generation: Differential
... synaptic interactions, and their modulation have been extensively characterized and modeled over the last 25 years. More recently, the genes encoding the voltage-dependent K ⫹ channels in this system have been cloned, and protocols for studying these molecular entities in individual identified pylor ...
... synaptic interactions, and their modulation have been extensively characterized and modeled over the last 25 years. More recently, the genes encoding the voltage-dependent K ⫹ channels in this system have been cloned, and protocols for studying these molecular entities in individual identified pylor ...
Fractionation of Membranes from Metschnikowi`a
... Radioocriw labelling. ['HDansyl chloride and Na'2sI were used as artificial markers of the plasma membrane (see Fig. 1). Both compounds react selectively and covalently under certain conditions with various amino acid residues of the plasma-membrane proteins accessible from the outside (Schibeci et ...
... Radioocriw labelling. ['HDansyl chloride and Na'2sI were used as artificial markers of the plasma membrane (see Fig. 1). Both compounds react selectively and covalently under certain conditions with various amino acid residues of the plasma-membrane proteins accessible from the outside (Schibeci et ...
Effects of 5-Hydroxytryptamine and Substance P on Neurons of the
... designated as the inferior salivatory nucleus (ISN). Immunocytochemical investigations have demonstrated the presence of a number of neuropeptides surrounding the ISN neurons. We have examined the neurophysiological effect of two of these neuropeptides on neurons of the ISN identified by retrograde ...
... designated as the inferior salivatory nucleus (ISN). Immunocytochemical investigations have demonstrated the presence of a number of neuropeptides surrounding the ISN neurons. We have examined the neurophysiological effect of two of these neuropeptides on neurons of the ISN identified by retrograde ...
Kinetic Analysis of the L-type Calcium Current in Enzymatically
... placed on the characteristics of the calcium influx through the dihydropyridinesensitive calcium channels (Campbell and Giles 1990; Pelzer et al. 1990). O n e of the main features of i c a - L is the presence of a time dependent decaying phase during a maintained depolarization. It was at first assu ...
... placed on the characteristics of the calcium influx through the dihydropyridinesensitive calcium channels (Campbell and Giles 1990; Pelzer et al. 1990). O n e of the main features of i c a - L is the presence of a time dependent decaying phase during a maintained depolarization. It was at first assu ...
The Functional Influence of Burst and Tonic Firing Mode on Synaptic
... PGN neurons that were monosynaptically connected with a simultaneously recorded LGNd cell resulted in IPSPs with a relatively fixed latency of ;1 msec. The mean amplitude of these single IPSPs varied considerably among different pairs of cells, ranging from just above the noise level (0.1– 0.2 mV) t ...
... PGN neurons that were monosynaptically connected with a simultaneously recorded LGNd cell resulted in IPSPs with a relatively fixed latency of ;1 msec. The mean amplitude of these single IPSPs varied considerably among different pairs of cells, ranging from just above the noise level (0.1– 0.2 mV) t ...
Action potential
In physiology, an action potential is a short-lasting event in which the electrical membrane potential of a cell rapidly rises and falls, following a consistent trajectory. Action potentials occur in several types of animal cells, called excitable cells, which include neurons, muscle cells, and endocrine cells, as well as in some plant cells. In neurons, they play a central role in cell-to-cell communication. In other types of cells, their main function is to activate intracellular processes. In muscle cells, for example, an action potential is the first step in the chain of events leading to contraction. In beta cells of the pancreas, they provoke release of insulin. Action potentials in neurons are also known as ""nerve impulses"" or ""spikes"", and the temporal sequence of action potentials generated by a neuron is called its ""spike train"". A neuron that emits an action potential is often said to ""fire"".Action potentials are generated by special types of voltage-gated ion channels embedded in a cell's plasma membrane. These channels are shut when the membrane potential is near the resting potential of the cell, but they rapidly begin to open if the membrane potential increases to a precisely defined threshold value. When the channels open (in response to depolarization in transmembrane voltage), they allow an inward flow of sodium ions, which changes the electrochemical gradient, which in turn produces a further rise in the membrane potential. This then causes more channels to open, producing a greater electric current across the cell membrane, and so on. The process proceeds explosively until all of the available ion channels are open, resulting in a large upswing in the membrane potential. The rapid influx of sodium ions causes the polarity of the plasma membrane to reverse, and the ion channels then rapidly inactivate. As the sodium channels close, sodium ions can no longer enter the neuron, and then they are actively transported back out of the plasma membrane. Potassium channels are then activated, and there is an outward current of potassium ions, returning the electrochemical gradient to the resting state. After an action potential has occurred, there is a transient negative shift, called the afterhyperpolarization or refractory period, due to additional potassium currents. This mechanism prevents an action potential from traveling back the way it just came.In animal cells, there are two primary types of action potentials. One type is generated by voltage-gated sodium channels, the other by voltage-gated calcium channels. Sodium-based action potentials usually last for under one millisecond, whereas calcium-based action potentials may last for 100 milliseconds or longer. In some types of neurons, slow calcium spikes provide the driving force for a long burst of rapidly emitted sodium spikes. In cardiac muscle cells, on the other hand, an initial fast sodium spike provides a ""primer"" to provoke the rapid onset of a calcium spike, which then produces muscle contraction.