• We are sorry, but NCBI web applications do not support your browser and may not function properly. More information
Logo of jphysiolThe Journal of Physiology SiteMembershipSubmissionJ Physiol
J Physiol. Jun 1973; 231(3): 549–574.
PMCID: PMC1350679

The binding of acetylcholine to receptors and its removal from the synaptic cleft

Abstract

1. Acetylcholine (ACh) noise and miniature end-plate potentials were recorded with focal external micro-electrodes.

2. The effect of prostigmine on the time course of the `molecular' and `quantal' transmitter actions was studied. Prostigmine (10-6 g/ml.) has little or no effect on the duration of the molecular `gating action', while it greatly prolongs the quantal conductance change.

3. After inhibition of ACh hydrolysis, the removal of the transmitter from the synapse is generally too slow to be accounted for by free diffusion. It is suggested that diffusion is delayed by binding to post-synaptic receptors. This is consistent with the finding that receptor blockage by curare or α-bungarotoxin shortens as well as reduces quantal transmitter action.

4. The correlated effects of the receptor-blocking agents, on size and time course of the miniature end-plate currents, were subjected to a simple analysis. Its result suggests that after inhibition of cholinesterase about two thrids of the quantal packet of ACh combines with post-synaptic receptors.

5. During focal external recording the effect of prostigmine on the time course of miniature end-plate potentials can become exaggerated due to what appears to be a compression artifact which obstructs outward diffusion of the transmitter.

Full text

Full text is available as a scanned copy of the original print version. Get a printable copy (PDF file) of the complete article (3.0M), or click on a page image below to browse page by page. Links to PubMed are also available for Selected References.

Selected References

These references are in PubMed. This may not be the complete list of references from this article.
  • DEL CASTILLO J, KATZ B. Localization of active spots within the neuromuscular junction of the frog. J Physiol. 1956 Jun 28;132(3):630–649. [PMC free article] [PubMed]
  • DEL CASTILLO J, KATZ B. Interaction at end-plate receptors between different choline derivatives. Proc R Soc Lond B Biol Sci. 1957 May 7;146(924):369–381. [PubMed]
  • ECCLES JC, JAEGER JC. The relationship between the mode of operation and the dimensions of the junctional regions at synapses and motor end-organs. Proc R Soc Lond B Biol Sci. 1958 Jan 1;148(930):38–56. [PubMed]
  • FATT P, KATZ B. An analysis of the end-plate potential recorded with an intracellular electrode. J Physiol. 1951 Nov 28;115(3):320–370. [PMC free article] [PubMed]
  • FATT P, KATZ B. Spontaneous subthreshold activity at motor nerve endings. J Physiol. 1952 May;117(1):109–128. [PMC free article] [PubMed]
  • Gage PW, Armstrong CM. Miniature end-plate currents in voltage-clamped muscle fibre. Nature. 1968 Apr 27;218(5139):363–365. [PubMed]
  • Gage PW, McBurney RN. Miniature end-plate currents and potentials generated by quanta of acetylcholine in glycerol-treated toad sartorius fibres. J Physiol. 1972 Oct;226(1):79–94. [PMC free article] [PubMed]
  • Hubbard JI, Wilson DF. Neuromuscular transmission in a mammalian preparation in the absence of blocking drugs and the effect of D-tubocurarine. J Physiol. 1973 Jan;228(2):307–325. [PMC free article] [PubMed]
  • KATZ B, MILEDI R. PROPAGATION OF ELECTRIC ACTIVITY IN MOTOR NERVE TERMINALS. Proc R Soc Lond B Biol Sci. 1965 Feb 16;161:453–482. [PubMed]
  • Katz B, Miledi R. Membrane noise produced by acetylcholine. Nature. 1970 Jun 6;226(5249):962–963. [PubMed]
  • Katz B, Miledi R. Further observations on acetylcholine noise. Nat New Biol. 1971 Jul 28;232(30):124–126. [PubMed]
  • Katz B, Miledi R. The statistical nature of the acetycholine potential and its molecular components. J Physiol. 1972 Aug;224(3):665–699. [PMC free article] [PubMed]
  • Katz B, Miledi R. The characteristics of 'end-plate noise' produced by different depolarizing drugs. J Physiol. 1973 May;230(3):707–717. [PMC free article] [PubMed]
  • Kordas M. The effect of membrane polarization on the time course of the end-plate current in frog sartorius muscle. J Physiol. 1969 Oct;204(2):493–502. [PMC free article] [PubMed]
  • Lee CY. Elapid neurotoxins and their mode of action. Clin Toxicol. 1970 Sep;3(3):457–472. [PubMed]
  • Magleby KL, Stevens CF. The effect of voltage on the time course of end-plate currents. J Physiol. 1972 May;223(1):151–171. [PMC free article] [PubMed]
  • Magleby KL, Stevens CF. A quantitative description of end-plate currents. J Physiol. 1972 May;223(1):173–197. [PMC free article] [PubMed]
  • Negrette J, Del Castillo J, Escobar I, Yankelevich G. Spreading activation of end-plate receptors by single transmitter quanta. Nat New Biol. 1972 Feb 2;235(57):158–159. [PubMed]
  • Potter LT. Synthesis, storage and release of [14C]acetylcholine in isolated rat diaphragm muscles. J Physiol. 1970 Jan;206(1):145–166. [PMC free article] [PubMed]

Articles from The Journal of Physiology are provided here courtesy of The Physiological Society

Formats:

Related citations in PubMed

See reviews...See all...

Cited by other articles in PMC

See all...

Links

  • Compound
    Compound
    PubChem Compound links
  • MedGen
    MedGen
    Related information in MedGen
  • PubMed
    PubMed
    PubMed citations for these articles
  • Substance
    Substance
    PubChem Substance links

Recent Activity

Your browsing activity is empty.

Activity recording is turned off.

Turn recording back on

See more...