Summary
1. Several different types of insect neurone are able to generate plateau potentials which can drive bursts of axonal action potentials. In locust these events are enabled by perfusing octopamine over the preparation. In cockroach motoneurones, plateau potentials are active, Ca-dependent events which appear to involve the participation of the soma and neurites. Plateau potentials may play a key role in determining the output of insect neuronal networks.
2. The somata of at least some cockroach motoneurones can generate Ca-dependent action potentials without any requirement to manipulate intracellular Ca2+ concentration or K currents. These action potentials, however, have only been observed in recordings made at least 1–2 hours after dissection of the nerve cord from the animal.
3. Dopamine has a voltage-dependent action upon the common inhibitory neurone (D3) of the cockroach prothoracic ganglion, such that it generates only a small inward current in the region of the resting potential; the magnitude of the current increases on depolarization, reaching a maximum near −10 to − 20 mV. Dopamine responses are mediated by receptors with a pharmacological profile that differs from either mammalian D-l or D-2 receptors.
3. Some insect neurones possess more than one class of ACh receptor. One has characteristics in common with the mammalian nicotinic receptor, operating a conventional non-specific cation channel. Another class of ACh receptor has characteristics closer to those of the mammalian muscarinic receptor. Activation of these ‘muscarinic’ receptors generates little or no response at the neuronal resting potential, but produces a large, long-lasting inward current at more positive potentials.
4. The voltage-dependence of responses to dopamine and ACh would have the consequence that neither substance would exert any significant effect on a quiescent neurone. They may, on the other hand, modulate the ability of the neurone to generate active events such as plateau potentials or somatic action potentials.
This is a preview of subscription content, log in via an institution to check access.
Access this chapter
Tax calculation will be finalised at checkout
Purchases are for personal use only
Preview
Unable to display preview. Download preview PDF.
References
Baker, J. R. and Pitman, R. M. (1989) Localization of biogenic amine-containing neurones in the ventral nerve cord of the cockroach (Periplaneta americana). Comp. Biochem. Physiol. 92C, 237–243.
Bensen, J. A. (1988) Bicuculline blocks the response to acetylcholine and nicotine but not to muscarine or GABA in isolated insect neuronal somata. Brain Res. 458, 65–71.
David, J. A. and Pitman, R. M. (1990) Functional muscarinic receptors on an identified neurone in the isolated metathoracic ganglion of the cockroach Periplaneta americana. J. Physiol. Lond. 429, 66 P.
David, J. A. and Pitman, R. M. (1992) The pharmacology of muscarinic receptors on the soma membrane of an identified cockroach motoneurone. J. Physiol., Lond. 446, 324.
David, J. A. and Sattelle, D. B. (1990) Ionic basis of membrane potential and of acetylcholine- induced currents in the cell body of the cockroach fast coxal depressor motor neurone. J. exp. Biol. 151, 21–39.
Davis, J. P. L. and Pitman, R. M. (1991) Characterization of receptors mediating the actions of dopamine on an identified inhibitory motoneurone of the cockroach. J. exp. Biol. 155, 203–217.
Dymond, G. R. and Evans, P. D. (1979) Biogenic amines in the nervous system of the cockroach, Periplaneta americana: association of octopamine with mushroom bodies and dorsal unpaired median (DUM) neurones. Insect Biochem. 9, 535–545.
Flamm, R. E. and Harris-Warrick, R. M. (1986a) Aminergic modulation in lobster stomatogastric ganglion. I. Effects on motor pattern and activity of neurons within the pyloric circuit. J. Neurophysiol. 55, 847–865.
Flamm, R. E. and Harris-Warrick, R. M. (1986b) Aminergic modulation in lobster stomatogastric ganglion. II. Target neurons of dopamine, octopamine, and serotonin within the pyloric circuit. J. Neurophysiol. 55, 866–881.
Gifford, A. N., Nicholson, R. A. and Pitman, R. M. (1991) The dopamine and 5-hydroxytryptamine content of locust and cockroach salivary neurones. J. exp. Biol. 161, 405–414.
Goodman, C. S. and Heitler, W. J. (1979) Electrical properties of insect neurones with spiking and non-spiking somata: normal, axotomized and colchicine-treated neurones. J. exp. Biol. 83, 95–121.
Hancox, J. C. and Pitman, R. M. (1991) Plateau potentials drive axonal impulse bursts in insect motoneurones. Proc. Roy. Soc., Ser B. 244, 33–38.
Hancox, J. C. and Pitman, R. M. (1992) A time-dependent excitability change in the soma of an identified insect motoneurone. J. exp. Biol. 162, 251–263.
Hue, B., Lapied, B. and Malecot, C. O. (1989) Do presynaptic muscarinic receptors regulate acetylcholine release in the central nervous system of the cockroach Periplaneta americana? J. exp. Biol. 142, 447–451.
Lapied, B., Le Corronc, H. and Hue, B. (1990) Sensitive nicotinic and mixed nicotinic-muscarinic receptors in insect neurosecretory cells. Brain Res. 533, 132–136.
Laurent, G. (1990) Voltage-dependent nonlinearities in the membrane of locust nonspiking local interneurons, and their significance for synaptic integration. J. Neurosci. 10, 2268–2280.
Laurent, G. (1991) Evidence for voltage-activated outward currents in the neuropilar mem-brane of locust nonspiking local interneurons. J. Neurosci. 11, 1713–1726.
Pitman, R. M. (1975) The ionic dependence of action potentials induced by colchicine in an insect motoneurone cell body. J. Physiol., Lond. 247, 511–520.
Pitman, R. M. (1979) Intracellular citrate or externally applied tetraethylammonium ions produce calcium-dependent action potentials in an insect motoneurone cell body. J. Physiol., Lond. 291, 327–337.
Pitman, R. M. (1985) Pharmacology of the insect central nervous system, in: Comprehensive Insect Physiology, Biochemistry and Pharmacology, pp. 5–54. Eds G. A. Kerkut and L. I. Gilbert. Pergamon, Oxford.
Pitman, R. M. (1988) Delayed effects of anoxia upon the electrical properties of an identified cockroach motoneurone. J. exp. Biol. 135, 95–108.
Pitman, R. M. and Baker, J. R. (1989) Dopamine responses recorded from a common inhibitory motoneurone of the cockroach (.Periplaneta americana). Comp. Biochem. Physiol. 92C, 245–251.
Pitman, R. M. and Davis, J. P. L. (1988) Pharmacological differentiation of responses to dopamine, octopamine and noradrenaline recorded from a cockroach motoneurone. Pest. Set 24, 311–323.
Pitman, R. M., Tweedle, C. D. and Cohen, M. J. (1972) Electrical responses of insect central neurons: augmentation by nerve section or colchicine. Science 178, 507–509.
Ramirez, J. M. and Pearson, K. G. (1991a) Octopamine induces bursting and plateau potentials in insect neurones. Brain Res. 549, 332–337.
Ramirez, J. M. and Pearson, K. G. (1991b) Octopaminergic modulation of interneurons in the flight system of the locust. J. Neurophysiol. 66, 1522–1537.
Robertson, R. M. (1986) Neuronal circuits controlling flight in the locust: central generation of the rhythm. Trends Neurosci. 9, 278–280.
Trimmer, B. A. and Weeks, J. C. (1989) Effects of nicotinic and muscarinic agents on an identified motoneurone and its direct afferent inputs in larval Manduca sexta. J. exp. Biol. 144, 303–337.
Author information
Authors and Affiliations
Editor information
Editors and Affiliations
Rights and permissions
Copyright information
© 1993 Birkhäuser Verlag Basel/Switzerland
About this chapter
Cite this chapter
Pitman, R.M., David, J.A., Hancox, J.C. (1993). Modulation of insect neurone properties. In: Pichon, Y. (eds) Comparative Molecular Neurobiology. EXS, vol 63. Birkhäuser Basel. https://doi.org/10.1007/978-3-0348-7265-2_22
Download citation
DOI: https://doi.org/10.1007/978-3-0348-7265-2_22
Publisher Name: Birkhäuser Basel
Print ISBN: 978-3-0348-7267-6
Online ISBN: 978-3-0348-7265-2
eBook Packages: Springer Book Archive