The Effects of Tetrodotoxin on the Slow Potential and Spikes in the Cardiac Ganglion of a Crab, Eriocheir Japonicus

Tazaki, Kenro

doi:10.2170/jjphysiol.21.529

Cited by 27 publications

(7 citation statements)

References 19 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The present investigation was inspired by a molecular study of the CG of C. borealis in which mRNA transcripts of LCs that encode for ion channel proteins were measured, revealing correlations between transcript numbers for many genes (Tobin et al, 2009). The CG network model was developed from biological CG data, especially the comprehensive studies performed by Tazaki and Cooke (Tazaki, 1971; Tazaki and Cooke, 1979a,b,c, 1983a,b, 1986, 1990; Cooke, 2002), and this model reproduced many features of the CG output, in particular the driver potential response of the LC, spontaneous bursting of the synaptically coupled large and small cells, and various essential features of both types of output. In addition to thoroughly characterizing the contribution of each ionic current to the properties of the driver potential, we varied the maximal conductances of the ionic currents in the LC soma and investigated relationships between the maximal conductances that preserved the form of the LC driver potential.…”

Section: Discussionmentioning

confidence: 99%

Coregulation of Ion Channel Conductances Preserves Output in a Computational Model of a Crustacean Cardiac Motor Neuron

Ball

Franklin

Tobin

et al. 2010

Journal of Neuroscience

View full text Add to dashboard Cite

Similar activity patterns at both neuron and network levels can arise from different combinations of membrane and synaptic conductance values. A strategy by which neurons may preserve their electrical output is via cell type-dependent balances of inward and outward currents. Measurements of mRNA transcripts that encode ion channel proteins within motor neurons in the crustacean cardiac ganglion recently revealed correlations between certain channel types. To determine whether balances of intrinsic currents potentially resulting from such correlations preserve certain electrical cell outputs, we developed a nominal biophysical model of the crustacean cardiac ganglion using biological data. Predictions from the nominal model showed that coregulation of ionic currents may preserve the key characteristics of motor neuron activity. We then developed a methodology of sampling a multidimensional parameter space to select an appropriate model set for meaningful comparison with variations in correlations seen in biological datasets.

show abstract

Section: Discussionmentioning

confidence: 99%

Coregulation of Ion Channel Conductances Preserves Output in a Computational Model of a Crustacean Cardiac Motor Neuron

Ball

Franklin

Tobin

et al. 2010

Journal of Neuroscience

View full text Add to dashboard Cite

show abstract

“…In Eriocheir cells the slow potential remains after the spike potentials are abolished by addition of tetrodotoxin to the medium (Tazaki, 1971). During the burst period the slow potential of Squilla and Eriocheir neurons and the first derivative of the relaxation oscillator slowly decreases from a point of maximum depolarization at the start of the burst period, and, as one might expect from this, the frequency of spikes slowly declines during the burst period in each of these cardiac ganglia (Watanabe et al, 1967;Tazaki, 1971;Maynard, 1955;Hartline and Cooke, 1969). Also, during the silent period membrane potential slowly becomes more positive in each case.…”

Section: Discussionmentioning

confidence: 99%

A Relaxation Oscillator Description of the Burst-Generating Mechanism in the Cardiac Ganglion of the Lobster, Homarus americanus

Mayeri

1973

The Journal of General Physiology

View full text Add to dashboard Cite

Properties of the neural mechanism responsible for generating the periodic burst of spike potentials in the nine ganglion neurons were investigated by applying brief, single shocks to the four small cells with extracellular electrodes placed near the trigger zones of the small cells. The shock elicited a burst if presented during the latter portion of the silent period, terminated a burst during the latter portion of the burst period, and was followed by a newly initiated burst during the early portion of the burst period. The resultant changes in burst and silent period durations were quantitatively described by a secondorder non-linear differential equation similar to the van der Pol equation for a relaxation oscillator. The equation also qualitatively described changes in firing threshold of the small cells during the burst cycle. The first derivative of the solution to the equation is similar to slow transmembrane potentials in neurons that are involved in generation of burst activity in other crustacean cardiac ganglia.

show abstract

“…Two additional procedures were utilized in order to demonstrate direct effects of proctolin on the large anterior cells: (1) application of tetrodotoxin (TTX, 3-6 x 10-7M) was used to eliminate spike mediated interactions between small and large cells (see Tazaki, 1971; ;…”

Section: Effects Of Proctolin On Isolated Large Cellsmentioning

confidence: 99%

“…Meanwhile, detailed transection and pharmacological experiments led several investigators to stress the endogenous nature of motorneuron rhythm and burst generation (Matsui, 1955;Watanabe, 1958;Connor, 1969;Matsui, Arinobu, and Naohiro, 1972;Tazaki, 1973;. The demonstration of TTXresistant, Ca' +-dependent driver potentials in motorneurons (Tazaki, 1971;Tazaki and Cooke, 1979b) led to the current view that rhythmic motor pattern generation results from a combination of integrated small cell inputs with the regenerative driver potential of large cells ; see also review by Hartline, 1979). Ganglionic rhythmicity is attributed to ramp or pacemaker potentials which have been recorded in small cells (Tameyasu, 1976;Tazaki and Cooke, 1979a).…”

Section: Network Architecture and Rhythmic Pattern Generation: A N Almentioning

confidence: 99%

Dual effects of proctolin on the rhythmic burst activity of the cardiac ganglion

Sullivan¹

1984

J. Neurobiol.

View full text Add to dashboard Cite

The neuropeptide proctolin has distinguishable excitatory effects upon premotor cells and motorneurons of Homarus cardiac ganglion. Proctolin's excitation of the small, premotor, posterior cells is rapid in onset (5-10 s) and readily reversible (less than 3 min). Prolonged bursts in small cells often produce a "doublet" ganglionic burst mode via interactions with large motorneuron burst-generating driver potentials. In contrast to small cell response, proctolin's direct excitatory effects upon motorneuron are slow in onset (60-90 s to peak) and long-lasting (10-20 min). The latter include: a concentration-dependent (10(-9)-10(-7)M) depolarization of the somatic membrane potential; increases in burst frequency and enhancement of the rate of depolarization of the interburst pacemaker potential. Experiments on isolated large cells indicate: the slow depolarization is produced by a decrease in the resting GK and proctolin can produce or enhance motorneuron autorhythmicity . A two- tiered non-hierarchical network model is proposed. The differential pharmacodynamics exhibited by the two cell types accounts for the sequential modes of ganglionic burst activity produced by proctolin.

show abstract

The Effects of Tetrodotoxin on the Slow Potential and Spikes in the Cardiac Ganglion of a Crab, Eriocheir Japonicus

Abstract: Summary The effects of tetrodotoxin on the electrical components slow potential and spikes have been studied in the crab cardiac ganglion cell.

Cited by 27 publications

References 19 publications

Coregulation of Ion Channel Conductances Preserves Output in a Computational Model of a Crustacean Cardiac Motor Neuron

Coregulation of Ion Channel Conductances Preserves Output in a Computational Model of a Crustacean Cardiac Motor Neuron

A Relaxation Oscillator Description of the Burst-Generating Mechanism in the Cardiac Ganglion of the Lobster, Homarus americanus

Dual effects of proctolin on the rhythmic burst activity of the cardiac ganglion

Contact Info

Product

Resources

About