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. 1974 Apr;238(2):313–328. doi: 10.1113/jphysiol.1974.sp010526

Studies of radiocalcium efflux in single barnacle muscle fibres: effects of procaine and external divalent cations

Stephen S Chen
PMCID: PMC1330882  PMID: 4840850

Abstract

1. 45Ca efflux from single barnacle muscle fibres loaded with radio-calcium by microinjection was studied.

2. The 45Ca washout curve consisted of three exponential phases with half-times of 4·8, 12·6 and 111·1 min.

3. Removal of external Ca2+ reduced 45Ca efflux by 65%. The 45Ca efflux recovered upon restoring external Ca2+, the magnitude of the recovery being dependent upon the external Ca2+ concentration. 10 mM procaine was found to reduce the magnitude of the recovery.

4. Removal of external Mg2+ resulted in a 38% increase in 45Ca efflux.

5. External application of procaine at pH 7·8 caused a dose-dependent inhibition of 45Ca efflux. The magnitude of the inhibition was reduced in the presence of low external Ca2+ concentrations. 10 mM procaine at pH 9·3 caused a biphasic effect: inhibition was followed by stimulation.

6. Microinjection of 0·5 M procaine caused only inhibition of 45Ca efflux, whereas microinjection of 1·5 M procaine caused stimulation followed by inhibition. These effects were observed at an external pH of 7·8 and 9·3.

7. Injection of 100 mM-EGTA abolished the stimulatory but not the inhibitory effect produced by procaine injection.

8. These results are interpreted as indicating that a major fraction of the 45Ca efflux involves Ca-Ca exchange which is inhibited by the charged form of procaine in a non-competitive manner at the external surface of the muscle fibre. The stimulatory action is attributed to release by procaine of Ca2+ from internal binding sites.

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Selected References

These references are in PubMed. This may not be the complete list of references from this article.

  1. ARIENS E. J., SIMONIS A. M. pH and drug action. Arch Int Pharmacodyn Ther. 1963 Feb 1;141:309–330. [PubMed] [Google Scholar]
  2. Ashley C. C., Caldwell P. C., Lowe A. G. The efflux of calcium from single crab and barnacle muscle fibres. J Physiol. 1972 Jun;223(3):735–755. doi: 10.1113/jphysiol.1972.sp009872. [DOI] [PMC free article] [PubMed] [Google Scholar]
  3. Ashley C. C., Ridgway E. B. On the relationships between membrane potential, calcium transient and tension in single barnacle muscle fibres. J Physiol. 1970 Jul;209(1):105–130. doi: 10.1113/jphysiol.1970.sp009158. [DOI] [PMC free article] [PubMed] [Google Scholar]
  4. Bianchi C. P., Bolton T. C. Action of local anesthetics on coupling systems in muscle. J Pharmacol Exp Ther. 1967 Aug;157(2):388–405. [PubMed] [Google Scholar]
  5. CALDWELL P. C. CALCIUM AND THE CONTRACTION OF MAIA MUSCLE FIBRES. Proc R Soc Lond B Biol Sci. 1964 Oct 27;160:512–516. doi: 10.1098/rspb.1964.0066. [DOI] [PubMed] [Google Scholar]
  6. CALDWELL P. C., WALSTER G. STUDIES ON THE MICRO-INJECTION OF VARIOUS SUBSTANCES INTO CRAB MUSCLE FIBRES. J Physiol. 1963 Nov;169:353–372. doi: 10.1113/jphysiol.1963.sp007261. [DOI] [PMC free article] [PubMed] [Google Scholar]
  7. Chen S., Bittar E. E., Tong E., Danielson B. G. Stimulation by caffeine of the calcium efflux in barnacle muscle fibers. Experientia. 1972 Jul 15;28(7):807–809. doi: 10.1007/BF01923144. [DOI] [PubMed] [Google Scholar]
  8. FEINSTEIN M. B. INHIBITION OF CAFFEINE RIGOR AND RADIOCALCIUM MOVEMENTS BY LOCAL ANESTHETICS IN FROG SARTORIUS MUSCLE. J Gen Physiol. 1963 Sep;47:151–172. doi: 10.1085/jgp.47.1.151. [DOI] [PMC free article] [PubMed] [Google Scholar]
  9. HODGKIN A. L., KEYNES R. D. Experiments on the injection of substances into squid giant axons by means of a microsyringe. J Physiol. 1956 Mar 28;131(3):592–616. doi: 10.1113/jphysiol.1956.sp005485. [DOI] [PMC free article] [PubMed] [Google Scholar]
  10. Isaacson A., Hinkes M. J., Taylor S. R. Contracture and twitch potentiation of fast and slow muscles of the rat at 20 and 37 C. Am J Physiol. 1970 Jan;218(1):33–41. doi: 10.1152/ajplegacy.1970.218.1.33. [DOI] [PubMed] [Google Scholar]
  11. SHANES A. M., BIANCHI C. P. The distribution and kinetics of release of radiocalcium in tendon and skeletal muscle. J Gen Physiol. 1959 May 20;42(5):1123–1137. doi: 10.1085/jgp.42.5.1123. [DOI] [PMC free article] [PubMed] [Google Scholar]
  12. Thorpe W. R., Seeman P. The site of action of caffeine and procaine in skeletal muscle. J Pharmacol Exp Ther. 1971 Nov;179(2):324–330. [PubMed] [Google Scholar]

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