Abstract
1. A study has been made of the effects of Sr2+ and Ba2+ ions at synapses in isolated superior cervical ganglia of guinea-pigs. Intracellular recordings of membrane potential were made from ganglion cells in the presence of different concentrations of Ca2+, Sr2+ and Ba2+ ions. 2. The addition of Sr2+ (2-5 mM) caused little change in resting membrane potential; in contrast, Ba2+ (1-6 mM) always depolarized the cells and prolonged the duration of action potentials. 3. The resting frequency of spontaneous miniature excitatory post-synaptic potentials (min. e.p.s.p.s) was briefly accelerated by the addition of either Sr2+ or Ba2+, but subsequently returned to about control levels. 4. Following replacement of Ca2+ by Sr2+, e.p.s.p.s could always be evoked during repetitive stimulation of preganglionic axons at a fixed latency after the nerve impulses ('phasic' transmitter release). Replacement of Ca2+ by Ba2+ produced many asynchronous e.p.s.p.s during trains of impulses ('residual' transmitter release). 5. By analysis of the interaction between Sr2+ and Ca2+, Sr2+ was shown to have a partial agonist action on 'phasic' transmitter release. The same analysis applied to Ba2+ failed to demonstrate either a partial agonist or antagonist action. 6. Both Sr2+ and Ba2+ prolonged e.p.s.p.s. Changes in Sr2+ could mainly be attributed to its effect on cell input resistance; Ba2+ may also prolong the time course of transmitter release. 7. The increased frequency of min. e.p.s.p.s which occurs during repetitive stimulation was potentiated by both Sr2+ and Ba2+, Ba2+ being about twice as potent as Sr2+. This activation of 'residual' transmitter release is independent of the action of these ions on 'phasic' release. 8. It is concluded that the reported maintenance by Ba2+ of acetyl-choline output from perfused ganglia results from the asynchronous release of large numbers of quanta during trains of impulses.
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Selected References
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- Alnaes E., Meiri U., Rahamimoff H., Rahamimoff R. Proceedings: Possible role of mitochondria in transmitter release. J Physiol. 1974 Aug;241(1):30P–31P. [PubMed] [Google Scholar]
- Baker P. F. Transport and metabolism of calcium ions in nerve. Prog Biophys Mol Biol. 1972;24:177–223. doi: 10.1016/0079-6107(72)90007-7. [DOI] [PubMed] [Google Scholar]
- Balnave R. J., Gage P. W. The inhibitory effect of manganese on transmitter release at the neuromuscular junction of the toad. Br J Pharmacol. 1973 Feb;47(2):339–352. doi: 10.1111/j.1476-5381.1973.tb08332.x. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Barrett E. F., Barret J. N. Separation of two voltage-sensitive potassium currents, and demonstration of a tetrodotoxin-resistant calcium current in frog motoneurones. J Physiol. 1976 Mar;255(3):737–774. doi: 10.1113/jphysiol.1976.sp011306. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Bennett M. R., Florin T., Hall R. The effect of calcium ions on the binomial statistic parameters which control acetylcholine release at synapses in striated muscle. J Physiol. 1975 May;247(2):429–446. doi: 10.1113/jphysiol.1975.sp010939. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Bennett M. R., Florin T., Pettigrew A. G. The effect of calcium ions on the binomial statistic parameters that control acetylcholine release at preganglionic nerve terminals. J Physiol. 1976 Jun;257(3):597–620. doi: 10.1113/jphysiol.1976.sp011387. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Benoit P. R., Mambrini J. Modification of transmitter release by ions which prolong the presynaptic action potential. J Physiol. 1970 Oct;210(3):681–695. doi: 10.1113/jphysiol.1970.sp009235. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Blackman J. G., Purves R. D. Intracellular recordings from ganglia of the thoracic sympathetic chain of the guinea-pig. J Physiol. 1969 Jul;203(1):173–198. doi: 10.1113/jphysiol.1969.sp008858. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Blaustein M. P. The interrelationship between sodium and calcium fluxes across cell membranes. Rev Physiol Biochem Pharmacol. 1974;70:33–82. doi: 10.1007/BFb0034293. [DOI] [PubMed] [Google Scholar]
- Crawford A. C. The dependence of evoked transmitter release on external calcium ions at very low mean quantal contents. J Physiol. 1974 Jul;240(2):255–278. doi: 10.1113/jphysiol.1974.sp010609. [DOI] [PMC free article] [PubMed] [Google Scholar]
- DOUGLAS W. W., LYWOOD D. W., STRAUB R. W. The stimulant effect of barium on the release of acetylcholine from the superior cervical ganglion. J Physiol. 1961 May;156:515–522. doi: 10.1113/jphysiol.1961.sp006690. [DOI] [PMC free article] [PubMed] [Google Scholar]
- DOUGLAS W. W., RUBIN R. P. STIMULANT ACTION OF BARIUM ON THE ADRENAL MEDULLA. Nature. 1964 Jul 18;203:305–307. doi: 10.1038/203305a0. [DOI] [PubMed] [Google Scholar]
- DOUGLAS W. W., RUBIN R. P. THE EFFECTS OF ALKALINE EARTHS AND OTHER DIVALENT CATIONS ON ADRENAL MEDULLARY SECRETION. J Physiol. 1964 Dec;175:231–241. doi: 10.1113/jphysiol.1964.sp007514. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Dodge F. A., Jr, Miledi R., Rahamimoff R. Strontium and quantal release of transmitter at the neuromuscular junction. J Physiol. 1969 Jan;200(1):267–283. doi: 10.1113/jphysiol.1969.sp008692. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Dodge F. A., Jr, Rahamimoff R. Co-operative action a calcium ions in transmitter release at the neuromuscular junction. J Physiol. 1967 Nov;193(2):419–432. doi: 10.1113/jphysiol.1967.sp008367. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Douglas W. W., Kanno T., Sampson S. R. Influence of the ionic environment on the membrane potential of adrenal chromaffin cells and on the depolarizing effect of acetylcholine. J Physiol. 1967 Jul;191(1):107–121. doi: 10.1113/jphysiol.1967.sp008239. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Edwards F. R., Hirst G. D., Silinsky E. M. Interaction between inhibitory and excitatory synaptic potentials at a peripheral neurone. J Physiol. 1976 Aug;259(3):647–663. doi: 10.1113/jphysiol.1976.sp011487. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Elmqvist D., Feldman D. S. Calcium dependence of spontaneous acetylcholine release at mammalian motor nerve terminals. J Physiol. 1965 Dec;181(3):487–497. doi: 10.1113/jphysiol.1965.sp007777. [DOI] [PMC free article] [PubMed] [Google Scholar]
- FRANKENHAEUSER B., HODGKIN A. L. The action of calcium on the electrical properties of squid axons. J Physiol. 1957 Jul 11;137(2):218–244. doi: 10.1113/jphysiol.1957.sp005808. [DOI] [PMC free article] [PubMed] [Google Scholar]
- FRANKENHAEUSER B. The effect of calcium on the myelinated nerve fibre. J Physiol. 1957 Jul 11;137(2):245–260. doi: 10.1113/jphysiol.1957.sp005809. [DOI] [PMC free article] [PubMed] [Google Scholar]
- FURSHPAN E. J. The effects of osmotic pressure changes on the spontaneous activity at motor nerve endings. J Physiol. 1956 Dec 28;134(3):689–697. doi: 10.1113/jphysiol.1956.sp005675. [DOI] [PMC free article] [PubMed] [Google Scholar]
- HOFFMAN B. F., SUCKLING E. E. Effect of several cations on transmembrane potentials of cardiac muscle. Am J Physiol. 1956 Aug;186(2):317–324. doi: 10.1152/ajplegacy.1956.186.2.317. [DOI] [PubMed] [Google Scholar]
- Hales C. N., Milner R. D. Cations and the secretion of insulin from rabbit pancreas in vitro. J Physiol. 1968 Nov;199(1):177–187. doi: 10.1113/jphysiol.1968.sp008647. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Hubbard J. I. Microphysiology of vertebrate neuromuscular transmission. Physiol Rev. 1973 Jul;53(3):674–723. doi: 10.1152/physrev.1973.53.3.674. [DOI] [PubMed] [Google Scholar]
- Hurlbut W. P., Longenecker H. B., Jr, Mauro A. Effects of calcium and magnesium on the frequency of miniature end-plate potentials during prolonged tetanization. J Physiol. 1971 Dec;219(1):17–38. doi: 10.1113/jphysiol.1971.sp009647. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Ishida A. Stimulus-secretion coupling on the oxytocin release from the isolated posterior pituitary lobe. Jpn J Physiol. 1968 Aug 15;18(4):471–480. doi: 10.2170/jjphysiol.18.471. [DOI] [PubMed] [Google Scholar]
- JENKINSON D. H. The nature of the antagonism between calcium and magnesium ions at the neuromuscular junction. J Physiol. 1957 Oct 30;138(3):434–444. doi: 10.1113/jphysiol.1957.sp005860. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Johnson E. W., Wernig A. The binomial nature of transmitter release at the crayfish neuromuscular junction. J Physiol. 1971 Nov;218(3):757–767. doi: 10.1113/jphysiol.1971.sp009642. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Kita H., Van Der Kloot W. Effects of the ionophore X-537A on acetylcholine release at the frog neuromuscular junction. J Physiol. 1976 Jul;259(1):177–198. doi: 10.1113/jphysiol.1976.sp011460. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Kita H., Van der Kloot W. Action of Co and Ni at the frog neuromuscular junction. Nat New Biol. 1973 Sep 12;245(141):52–53. doi: 10.1038/newbio245052a0. [DOI] [PubMed] [Google Scholar]
- Laskowski M. B., Thies R. Interactions between calcium and barium on the spontaneous release of transmitter from mammalian motor nerve terminals. Int J Neurosci. 1972 Jul;4(1):11–16. doi: 10.3109/00207457209147159. [DOI] [PubMed] [Google Scholar]
- MARTIN A. R., PILAR G. DUAL MODE OF SYNAPTIC TRANSMISSION IN THE AVIAN CILIARY GANGLION. J Physiol. 1963 Sep;168:443–463. doi: 10.1113/jphysiol.1963.sp007202. [DOI] [PMC free article] [PubMed] [Google Scholar]
- McLachlan E. M. An analysis of the release of acetylcholine from preganglionic nerve terminals. J Physiol. 1975 Feb;245(2):447–466. doi: 10.1113/jphysiol.1975.sp010855. [DOI] [PMC free article] [PubMed] [Google Scholar]
- McLachlan E. M. Changes in statistical release parameters during prolonged stimulation of preganglionic nerve terminals. J Physiol. 1975 Dec;253(2):477–491. doi: 10.1113/jphysiol.1975.sp011201. [DOI] [PMC free article] [PubMed] [Google Scholar]
- McLachlan E. M. Electrophysiological evidence for the second store of ACh in preganglionic nerve terminals. Brain Res. 1975 Nov 14;98(2):373–376. doi: 10.1016/0006-8993(75)90017-7. [DOI] [PubMed] [Google Scholar]
- McLachlan E. M. The formation of synapses in mammalian sympathetic ganglia reinnervated with preganglionic or somatic nerves. J Physiol. 1974 Feb;237(1):217–242. doi: 10.1113/jphysiol.1974.sp010479. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Meiri U., Rahamimoff R. Activation of transmitter release by strontium and calcium ions at the neuromuscular junction. J Physiol. 1971 Jul;215(3):709–726. doi: 10.1113/jphysiol.1971.sp009493. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Miledi R., Thies R. Tetanic and post-tetanic rise in frequency of miniature end-plate potentials in low-calcium solutions. J Physiol. 1971 Jan;212(1):245–257. doi: 10.1113/jphysiol.1971.sp009320. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Rahamimoff R., Yaari Y. Delayed release of transmitter at the frog neuromuscular junction. J Physiol. 1973 Jan;228(1):241–257. doi: 10.1113/jphysiol.1973.sp010084. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Robinson J. Estimation of parameters for a model of transmitter release at synapses. Biometrics. 1976 Mar;32(1):61–68. [PubMed] [Google Scholar]
- Rotshenker S., Erulkar S. D., Rahamimoff R. Reduction in the frequency of miniature end-plate potentials by nerve stimulation in low calcium solutions. Brain Res. 1976 Jan 16;101(2):362–365. doi: 10.1016/0006-8993(76)90277-8. [DOI] [PubMed] [Google Scholar]
- SHANES A. M. Electrochemical aspects of physiological and pharmacological action in excitable cells. I. The resting cell and its alteration by extrinsic factors. Pharmacol Rev. 1958 Mar;10(1):59–164. [PubMed] [Google Scholar]
- WERMAN R., GRUNDFEST H. Graded and all-or-none electrogenesis in arthropod muscle. II. The effects of alkali-earth and onium ions on lobster muscle fibers. J Gen Physiol. 1961 May;44:997–1027. doi: 10.1085/jgp.44.5.997. [DOI] [PMC free article] [PubMed] [Google Scholar]