Electrophysiological analysis of the neurotoxic action of a funnel-web spider toxin, δ-atracotoxin-Hv1a, on insect voltage-gated Na<sup>+</sup> channels

Grolleau, F; Stankiewicz, M; Birinyi-Strachan, L; Wang, XH; Nicholson, GM; Pelhate, M; Lapied, B

Electrophysiological analysis of the neurotoxic action of a funnel-web spider toxin, δ-atracotoxin-Hv1a, on insect voltage-gated Na<sup>+</sup> channels

Grolleau, F Stankiewicz, M Birinyi-Strachan, L Wang, XH Nicholson, GM

Pelhate, M Lapied, B

Permalink

Publication Type:: Journal Article
Citation:: Journal of Experimental Biology, 2001, 204 (4), pp. 711 - 721
Issue Date:: 2001-01-01

Open Access

Copyright Clearance Process

Recently Added
In Progress
Open Access

This item is open access.

Adobe PDF

Download full textAdobe PDF (310.15 kB)

View statistics

Full metadata record

Field	Value	Language
dc.contributor.author	Grolleau, F	en_US
dc.contributor.author	Stankiewicz, M	en_US
dc.contributor.author	Birinyi-Strachan, L	en_US
dc.contributor.author	Wang, XH	en_US
dc.contributor.author	Nicholson, GM https://orcid.org/0000-0002-4277-4296	en_US
dc.contributor.author	Pelhate, M	en_US
dc.contributor.author	Lapied, B	en_US
dc.date.issued	2001-01-01	en_US
dc.identifier.citation	Journal of Experimental Biology, 2001, 204 (4), pp. 711 - 721	en_US
dc.identifier.issn	0022-0949	en_US
dc.identifier.uri	http://hdl.handle.net/10453/5728
dc.description.abstract	The effects of δ-ACTX-Hv1a, purified from the venom of the funnel-web spider Hadronyche versuta, were studied on the isolated giant axon and dorsal unpaired median (DUM) neurones of the cockroach Periplaneta americana under current- and voltage-clamp conditions using the double oil-gap technique for single axons and the patch-clamp technique for neurones. In parallel, the effects of the toxin were investigated on the excitability of rat dorsal root ganglion (DRG) neurones. In both DRG and DUM neurones, δ-ACTX-Hv1a induced spontaneous repetitive firing accompanied by plateau potentials. However, in the case of DUM neurones, plateau action potentials were facilitated when the membrane was artificially hyperpolarized. In cockroach giant axons, δ-ACTX-Hv1a also produced plateau action potentials, but only when the membrane was pre-treated with 3-4 diaminopyridine. Under voltage-clamp conditions, δ-ACTX-Hv1a specifically affected voltage-gated Na+ channels in both axons and DUM neurones. Both the current/voltage and conductance/voltage curves of the δ-ACTX-Hv1a-modified inward current were shifted 10 mV to the left of control curves. In the presence of δ-ACTX-Hv1a, steady-state Na+ channel inactivation became incomplete, causing the appearance of a non-inactivating component at potentials more positive than -40mV. The amplitude of this non-inactivating component was dependent on the holding potential. From this study, it is concluded that, in insect neurones, δ-ACTX-Hv1a mainly affects Na+ channel inactivation by a mechanism that differs slightly from that of scorpion α-toxins.	en_US
dc.relation.ispartof	Journal of Experimental Biology	en_US
dc.subject.classification	Physiology	en_US
dc.subject.mesh	Ganglia, Spinal	en_US
dc.subject.mesh	Neurons	en_US
dc.subject.mesh	Axons	en_US
dc.subject.mesh	Animals	en_US
dc.subject.mesh	Rats	en_US
dc.subject.mesh	Periplaneta	en_US
dc.subject.mesh	Sodium Channels	en_US
dc.subject.mesh	Insect Proteins	en_US
dc.subject.mesh	Spider Venoms	en_US
dc.subject.mesh	Neurotoxins	en_US
dc.subject.mesh	Patch-Clamp Techniques	en_US
dc.subject.mesh	Action Potentials	en_US
dc.subject.mesh	Kinetics	en_US
dc.subject.mesh	Female	en_US
dc.subject.mesh	Male	en_US
dc.title	Electrophysiological analysis of the neurotoxic action of a funnel-web spider toxin, δ-atracotoxin-Hv1a, on insect voltage-gated Na<sup>+</sup> channels	en_US
dc.type	Journal Article
utslib.citation.volume	4	en_US
utslib.citation.volume	204	en_US
utslib.for	060808 Invertebrate Biology	en_US
utslib.for	030401 Biologically Active Molecules	en_US
utslib.for	06 Biological Sciences	en_US
utslib.for	11 Medical and Health Sciences	en_US
pubs.embargo.period	Not known	en_US
pubs.organisational-group	/University of Technology Sydney
pubs.organisational-group	/University of Technology Sydney/Faculty of Science
pubs.organisational-group	/University of Technology Sydney/Strength - CHT - Health Technologies
utslib.copyright.status	open_access
pubs.issue	4	en_US
pubs.publication-status	Published	en_US
pubs.volume	204	en_US

Abstract:

The effects of δ-ACTX-Hv1a, purified from the venom of the funnel-web spider Hadronyche versuta, were studied on the isolated giant axon and dorsal unpaired median (DUM) neurones of the cockroach Periplaneta americana under current- and voltage-clamp conditions using the double oil-gap technique for single axons and the patch-clamp technique for neurones. In parallel, the effects of the toxin were investigated on the excitability of rat dorsal root ganglion (DRG) neurones. In both DRG and DUM neurones, δ-ACTX-Hv1a induced spontaneous repetitive firing accompanied by plateau potentials. However, in the case of DUM neurones, plateau action potentials were facilitated when the membrane was artificially hyperpolarized. In cockroach giant axons, δ-ACTX-Hv1a also produced plateau action potentials, but only when the membrane was pre-treated with 3-4 diaminopyridine. Under voltage-clamp conditions, δ-ACTX-Hv1a specifically affected voltage-gated Na+ channels in both axons and DUM neurones. Both the current/voltage and conductance/voltage curves of the δ-ACTX-Hv1a-modified inward current were shifted 10 mV to the left of control curves. In the presence of δ-ACTX-Hv1a, steady-state Na+ channel inactivation became incomplete, causing the appearance of a non-inactivating component at potentials more positive than -40mV. The amplitude of this non-inactivating component was dependent on the holding potential. From this study, it is concluded that, in insect neurones, δ-ACTX-Hv1a mainly affects Na+ channel inactivation by a mechanism that differs slightly from that of scorpion α-toxins.

Please use this identifier to cite or link to this item:

http://hdl.handle.net/10453/5728