Abstract
The toxin fraction (FTX) and peptide omega-Aga-IVA from the venom of the funnel-web spider Agelenopsis aperta, as well as a synthetic analogue of FTX, specifically block the P-type voltage-dependent Ca2+ channel (VDCC). The effects of these toxins on synaptic transmission were studied in the neuromuscular synapses of the crayfish opener muscle, which has a single excitatory and a single inhibitory motoneuron. FTX selectively and reversibly blocked excitatory and inhibitory postsynaptic currents and potentials in a dose-dependent manner. FTX had no effect on (i) resting and postsynaptic membrane conductance, (ii) postsynaptic L-type VDCC, and (iii) both glutamate- and gamma-aminobutyric acid-induced postsynaptic responses. Mean amplitude and frequency of miniature postsynaptic potentials were unchanged by FTX. The postsynaptic VDCC was inhibited by nifedipine, a selective dihydropyridine antagonist of L-type VDCC, whereas synaptic transmission was unaffected. Transmission was also undisturbed by omega-conotoxin, suggesting that N-type VDCCs are not involved. The peptide omega-Aga-IVA blocked excitatory and inhibitory transmission without affecting postsynaptic VDCC. Synaptic transmission was also blocked by synthetic FTX. We conclude that presynaptic P-type VDCCs are involved in both evoked excitatory and inhibitory transmitter release in crayfish neuromuscular synapses.
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- Aosaki T., Kasai H. Characterization of two kinds of high-voltage-activated Ca-channel currents in chick sensory neurons. Differential sensitivity to dihydropyridines and omega-conotoxin GVIA. Pflugers Arch. 1989 Jun;414(2):150–156. doi: 10.1007/BF00580957. [DOI] [PubMed] [Google Scholar]
- Araque A., Ferreira W., Lucas S., Buño W. Glutamatergic postsynaptic block by Pamphobeteus spider venoms in crayfish. Brain Res. 1992 Jan 31;571(1):109–114. doi: 10.1016/0006-8993(92)90515-b. [DOI] [PubMed] [Google Scholar]
- Atchison W. D. Dihydropyridine-sensitive and -insensitive components of acetylcholine release from rat motor nerve terminals. J Pharmacol Exp Ther. 1989 Nov;251(2):672–678. [PubMed] [Google Scholar]
- Bittner G. D. Synaptic plasticity at the crayfish opener neuromuscular preparation. J Neurobiol. 1989 Jul;20(5):386–408. doi: 10.1002/neu.480200510. [DOI] [PubMed] [Google Scholar]
- Carbone E., Swandulla D. Neuronal calcium channels: kinetics, blockade and modulation. Prog Biophys Mol Biol. 1989;54(1):31–58. doi: 10.1016/0079-6107(89)90008-4. [DOI] [PubMed] [Google Scholar]
- Cazalis M., Dayanithi G., Nordmann J. J. Hormone release from isolated nerve endings of the rat neurohypophysis. J Physiol. 1987 Sep;390:55–70. doi: 10.1113/jphysiol.1987.sp016686. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Ceña V., Nicolas G. P., Sanchez-Garcia P., Kirpekar S. M., Garcia A. G. Pharmacological dissection of receptor-associated and voltage-sensitive ionic channels involved in catecholamine release. Neuroscience. 1983 Dec;10(4):1455–1462. doi: 10.1016/0306-4522(83)90126-4. [DOI] [PubMed] [Google Scholar]
- Cherksey B. D., Sugimori M., Llinás R. R. Properties of calcium channels isolated with spider toxin, FTX. Ann N Y Acad Sci. 1991;635:80–89. doi: 10.1111/j.1749-6632.1991.tb36483.x. [DOI] [PubMed] [Google Scholar]
- DEL CASTILLO J., KATZ B. The effect of magnesium on the activity of motor nerve endings. J Physiol. 1954 Jun 28;124(3):553–559. doi: 10.1113/jphysiol.1954.sp005128. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Hencek M., Zachar J. Calcium currents and conductances in the msucle membrane of the crayfish. J Physiol. 1977 Jun;268(1):51–71. doi: 10.1113/jphysiol.1977.sp011846. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Hirning L. D., Fox A. P., McCleskey E. W., Olivera B. M., Thayer S. A., Miller R. J., Tsien R. W. Dominant role of N-type Ca2+ channels in evoked release of norepinephrine from sympathetic neurons. Science. 1988 Jan 1;239(4835):57–61. doi: 10.1126/science.2447647. [DOI] [PubMed] [Google Scholar]
- Kawagoe R., Onodera K., Takeuchi A. Release of glutamate from the crayfish neuromuscular junction. J Physiol. 1981 Mar;312:225–236. doi: 10.1113/jphysiol.1981.sp013625. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Kerr L. M., Yoshikami D. A venom peptide with a novel presynaptic blocking action. Nature. 1984 Mar 15;308(5956):282–284. doi: 10.1038/308282a0. [DOI] [PubMed] [Google Scholar]
- Krizanova O., Novotova M., Zachar J. Characterization of DHP binding protein in crayfish striated muscle. FEBS Lett. 1990 Jul 16;267(2):311–315. doi: 10.1016/0014-5793(90)80951-e. [DOI] [PubMed] [Google Scholar]
- Lindgren C. A., Moore J. W. Identification of ionic currents at presynaptic nerve endings of the lizard. J Physiol. 1989 Jul;414:201–222. doi: 10.1113/jphysiol.1989.sp017684. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Llinás R., Sugimori M., Lin J. W., Cherksey B. Blocking and isolation of a calcium channel from neurons in mammals and cephalopods utilizing a toxin fraction (FTX) from funnel-web spider poison. Proc Natl Acad Sci U S A. 1989 Mar;86(5):1689–1693. doi: 10.1073/pnas.86.5.1689. [DOI] [PMC free article] [PubMed] [Google Scholar]
- McCleskey E. W., Fox A. P., Feldman D. H., Cruz L. J., Olivera B. M., Tsien R. W., Yoshikami D. Omega-conotoxin: direct and persistent blockade of specific types of calcium channels in neurons but not muscle. Proc Natl Acad Sci U S A. 1987 Jun;84(12):4327–4331. doi: 10.1073/pnas.84.12.4327. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Miller R. J. Multiple calcium channels and neuronal function. Science. 1987 Jan 2;235(4784):46–52. doi: 10.1126/science.2432656. [DOI] [PubMed] [Google Scholar]
- Mintz I. M., Venema V. J., Swiderek K. M., Lee T. D., Bean B. P., Adams M. E. P-type calcium channels blocked by the spider toxin omega-Aga-IVA. Nature. 1992 Feb 27;355(6363):827–829. doi: 10.1038/355827a0. [DOI] [PubMed] [Google Scholar]
- Olivera B. M., Gray W. R., Zeikus R., McIntosh J. M., Varga J., Rivier J., de Santos V., Cruz L. J. Peptide neurotoxins from fish-hunting cone snails. Science. 1985 Dec 20;230(4732):1338–1343. doi: 10.1126/science.4071055. [DOI] [PubMed] [Google Scholar]
- Perney T. M., Hirning L. D., Leeman S. E., Miller R. J. Multiple calcium channels mediate neurotransmitter release from peripheral neurons. Proc Natl Acad Sci U S A. 1986 Sep;83(17):6656–6659. doi: 10.1073/pnas.83.17.6656. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Plummer M. R., Logothetis D. E., Hess P. Elementary properties and pharmacological sensitivities of calcium channels in mammalian peripheral neurons. Neuron. 1989 May;2(5):1453–1463. doi: 10.1016/0896-6273(89)90191-8. [DOI] [PubMed] [Google Scholar]
- Protti D. A., Szczupak L., Scornik F. S., Uchitel O. D. Effect of omega-conotoxin GVIA on neurotransmitter release at the mouse neuromuscular junction. Brain Res. 1991 Aug 23;557(1-2):336–339. doi: 10.1016/0006-8993(91)90156-p. [DOI] [PubMed] [Google Scholar]
- Reynolds I. J., Wagner J. A., Snyder S. H., Thayer S. A., Olivera B. M., Miller R. J. Brain voltage-sensitive calcium channel subtypes differentiated by omega-conotoxin fraction GVIA. Proc Natl Acad Sci U S A. 1986 Nov;83(22):8804–8807. doi: 10.1073/pnas.83.22.8804. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Rivier J., Galyean R., Gray W. R., Azimi-Zonooz A., McIntosh J. M., Cruz L. J., Olivera B. M. Neuronal calcium channel inhibitors. Synthesis of omega-conotoxin GVIA and effects on 45Ca uptake by synaptosomes. J Biol Chem. 1987 Jan 25;262(3):1194–1198. [PubMed] [Google Scholar]
- Stanley E. F., Goping G. Characterization of a calcium current in a vertebrate cholinergic presynaptic nerve terminal. J Neurosci. 1991 Apr;11(4):985–993. doi: 10.1523/JNEUROSCI.11-04-00985.1991. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Takeuchi A., Takeuchi N. A study of the action of picrotoxin on the inhibitory neuromuscular junction of the crayfish. J Physiol. 1969 Nov;205(2):377–391. doi: 10.1113/jphysiol.1969.sp008972. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Tsien R. W., Lipscombe D., Madison D. V., Bley K. R., Fox A. P. Multiple types of neuronal calcium channels and their selective modulation. Trends Neurosci. 1988 Oct;11(10):431–438. doi: 10.1016/0166-2236(88)90194-4. [DOI] [PubMed] [Google Scholar]
- Turner T. J., Adams M. E., Dunlap K. Calcium channels coupled to glutamate release identified by omega-Aga-IVA. Science. 1992 Oct 9;258(5080):310–313. doi: 10.1126/science.1357749. [DOI] [PubMed] [Google Scholar]
- Uchitel O. D., Protti D. A., Sanchez V., Cherksey B. D., Sugimori M., Llinás R. P-type voltage-dependent calcium channel mediates presynaptic calcium influx and transmitter release in mammalian synapses. Proc Natl Acad Sci U S A. 1992 Apr 15;89(8):3330–3333. doi: 10.1073/pnas.89.8.3330. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Venema V. J., Swiderek K. M., Lee T. D., Hathaway G. M., Adams M. E. Antagonism of synaptosomal calcium channels by subtypes of omega-agatoxins. J Biol Chem. 1992 Feb 5;267(4):2610–2615. [PubMed] [Google Scholar]
- Yawo H., Momiyama A. Re-evaluation of calcium currents in pre- and postsynaptic neurones of the chick ciliary ganglion. J Physiol. 1993 Jan;460:153–172. doi: 10.1113/jphysiol.1993.sp019464. [DOI] [PMC free article] [PubMed] [Google Scholar]