Skip to main content
NCBI home page
British Journal of Pharmacology logoLink to British Journal of Pharmacology
. 1983 Aug;79(4):855–862. doi: 10.1111/j.1476-5381.1983.tb10529.x

Homotaurine: a GABAB antagonist in guinea-pig ileum.

A Giotti, S Luzzi, S Spagnesi, L Zilletti
PMCID: PMC2044932  PMID: 6652358

Abstract

Homotaurine (3-aminopropane sulphonic acid) did not inhibit the twitch response in guinea-pig ileum longitudinal muscle whilst gamma-aminobutyric acid (GABA) and (-)-baclofen evoked dose-dependent inhibitions. The inhibitory effects of GABA and (-)-baclofen were prevented in the presence of homotaurine 2 X 10(-4) and 10(-3) M. The log dose-effect curves of GABA and (-)-baclofen were shifted in a parallel manner compatible with competitive antagonism. The pA2 of homotaurine with GABA (4.22 +/- 0.05) and (-)-baclofen (4.26 +/- 0.1) were the same. Homotaurine did not antagonize the inhibitory effects of morphine (ED50 4 X 10(-7) M), noradrenaline (ED50 10(-6) M) or ATP (ED50 1.5 X 10(-5) M). The inferior homologue of homotaurine, taurine 10(-3) M, did not modify the inhibitory effects of GABA and (-)-baclofen. Picrotoxin 5 X 10(-5) M antagonized GABAA receptor-mediated contraction but did not affect GABAB receptor-mediated inhibition. At the same concentration the drug did not influence the antagonistic action of homotaurine, thus showing no GABAA receptor-mediated interference. It may be concluded that homotaurine is a competitive antagonist of GABAB mediated effects in the guinea-pig ileum.

Full text

PDF
855

Selected References

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

  1. Bowery N. G., Brown D. A. Depolarizing actions of gamma-aminobutyric acid and related compounds on rat superior cervical ganglia in vitro. Br J Pharmacol. 1974 Feb;50(2):205–218. doi: 10.1111/j.1476-5381.1974.tb08563.x. [DOI] [PMC free article] [PubMed] [Google Scholar]
  2. Bowery N. G., Doble A., Hill D. R., Hudson A. L., Shaw J. S., Turnbull M. J., Warrington R. Bicuculline-insensitive GABA receptors on peripheral autonomic nerve terminals. Eur J Pharmacol. 1981 Apr 24;71(1):53–70. doi: 10.1016/0014-2999(81)90386-1. [DOI] [PubMed] [Google Scholar]
  3. Clark A. J. The antagonism of acetyl choline by atropine. J Physiol. 1926 Aug 6;61(4):547–556. doi: 10.1113/jphysiol.1926.sp002315. [DOI] [PMC free article] [PubMed] [Google Scholar]
  4. Curtis D. R., Duggan A. W., Felix D., Johnston G. A. Bicuculline, an antagonist of GABA and synaptic inhibition in the spinal cord of the cat. Brain Res. 1971 Sep 10;32(1):69–96. doi: 10.1016/0006-8993(71)90156-9. [DOI] [PubMed] [Google Scholar]
  5. Curtis D. R., Johnston G. A. Amino acid transmitters in the mammalian central nervous system. Ergeb Physiol. 1974;69(0):97–188. doi: 10.1007/3-540-06498-2_3. [DOI] [PubMed] [Google Scholar]
  6. Enna S. J., Snyder S. H. Properties of gamma-aminobutyric acid (GABA) receptor binding in rat brain synaptic membrane fractions. Brain Res. 1975 Dec 12;100(1):81–97. doi: 10.1016/0006-8993(75)90243-7. [DOI] [PubMed] [Google Scholar]
  7. Giotti A., Luzzi S., Spagnesi S., Zilletti L. GABAA and GABAB receptor-mediated effects in guinea-pig ileum. Br J Pharmacol. 1983 Mar;78(3):469–478. doi: 10.1111/j.1476-5381.1983.tb08807.x. [DOI] [PMC free article] [PubMed] [Google Scholar]
  8. Jessen K. R., Mirsky R., Dennison M. E., Burnstock G. GABA may be a neurotransmitter in the vertebrate peripheral nervous system. Nature. 1979 Sep 6;281(5726):71–74. doi: 10.1038/281071a0. [DOI] [PubMed] [Google Scholar]
  9. Kaplita P. V., Waters D. H., Triggle D. J. gamma-Aminobutyric acid action in guinea-pig ileal myenteric plexus. Eur J Pharmacol. 1982 Apr 8;79(1-2):43–51. doi: 10.1016/0014-2999(82)90573-8. [DOI] [PubMed] [Google Scholar]
  10. Muhyaddin M., Roberts P. J., Woodruff G. N. Presynaptic gamma-aminobutyric acid receptors in the rat anococcygeus muscle and their antagonism by 5-aminovaleric acid. Br J Pharmacol. 1982 Sep;77(1):163–168. doi: 10.1111/j.1476-5381.1982.tb09282.x. [DOI] [PMC free article] [PubMed] [Google Scholar]
  11. PATON W. D. CHOLINERGIC TRANSMISSION AND ACETYLCHOLINE OUTPUT. Can J Biochem Physiol. 1963 Dec;41:2637–2653. [PubMed] [Google Scholar]
  12. Paton W. D., Vizi E. S. The inhibitory action of noradrenaline and adrenaline on acetylcholine output by guinea-pig ileum longitudinal muscle strip. Br J Pharmacol. 1969 Jan;35(1):10–28. doi: 10.1111/j.1476-5381.1969.tb07964.x. [DOI] [PMC free article] [PubMed] [Google Scholar]
  13. Paton W. D., Zar M. A. The origin of acetylcholine released from guinea-pig intestine and longitudinal muscle strips. J Physiol. 1968 Jan;194(1):13–33. doi: 10.1113/jphysiol.1968.sp008392. [DOI] [PMC free article] [PubMed] [Google Scholar]
  14. Sgaragli G. P., Carlà V., Magnani M., Giotti A. Homotaurine and muscimol mimic taurine and GABA effects on muscle tone and temperature regulation. Naunyn Schmiedebergs Arch Pharmacol. 1978 Nov;305(2):155–158. doi: 10.1007/BF00508286. [DOI] [PubMed] [Google Scholar]
  15. Svenneby G., Roberts E. Bicuculline and N-methylbicuculline--competitive inhibitors of brain acetylcholinesterase. J Neurochem. 1973 Oct;21(4):1025–1026. doi: 10.1111/j.1471-4159.1973.tb07551.x. [DOI] [PubMed] [Google Scholar]
  16. VAN ROSSUM J. M. Cumulative dose-response curves. II. Technique for the making of dose-response curves in isolated organs and the evaluation of drug parameters. Arch Int Pharmacodyn Ther. 1963;143:299–330. [PubMed] [Google Scholar]

Articles from British Journal of Pharmacology are provided here courtesy of The British Pharmacological Society

RESOURCES