Skip to main content
NCBI home page
British Journal of Pharmacology logoLink to British Journal of Pharmacology
. 1989 Feb;96(2):313–318. doi: 10.1111/j.1476-5381.1989.tb11819.x

Binding of [3H]-muscimol to GABAA sites in the guinea-pig urinary bladder: biochemical assay and autoradiography.

S L Erdö 1, M C Mione 1, F Amenta 1, J R Wolff 1
PMCID: PMC1854352  PMID: 2538188

Abstract

1. The specific binding of [3H]-muscimol, a gamma-aminobutyric acidA receptor (GABAA) agonist, to whole membranes of the guinea-pig urinary bladder was examined. In addition, the distribution of specific muscimol binding sites within the bladder was visualized by autoradiography. 2. It was demonstrated that in a frozen-thawed whole membrane preparation of the organ the specific binding of [3H]-muscimol is reproducible, reversible and saturable. 3. Saturable binding was of a single component with an equilibrium dissociation constant (Kd) of 12 nM and a maximal density (Bmax) of about 80 fmol mg-1 protein. 4. In displacement experiments with several model compounds, [3H]-muscimol binding sites showed the characteristics of a GABAA receptor site. 5. Autoradiographic experiments revealed uneven distribution of specifically bound [3H]-muscimol in the bladder. The density of binding sites was high in clusters within the smooth muscle layers of the bladder fundus and of the urethra, while the apex and the neck were not specifically labelled. 6. The present findings show that GABAA type receptor sites in the guinea-pig urinary bladder may be labelled by [3H]-muscimol in a specific and reproducible manner. Moreover, the localization of these binding sites is consistent with the presence of GABAA receptors in only a subpopulation of vesical ganglia.

Full text

PDF
313

Images in this article

316Figure 3
on p.316
316Figure 4
on p.316

Selected References

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

  1. Amenta F., Erdo S. L., Mione M. C., Napoleone P. 3H-muscimol binding sites within guinea pig ovary: a histoautoradiographic study. Pharmacology. 1986;32(4):202–207. doi: 10.1159/000138170. [DOI] [PubMed] [Google Scholar]
  2. Bowery N. G., Hill D. R., Hudson A. L. Characteristics of GABAB receptor binding sites on rat whole brain synaptic membranes. Br J Pharmacol. 1983 Jan;78(1):191–206. doi: 10.1111/j.1476-5381.1983.tb09380.x. [DOI] [PMC free article] [PubMed] [Google Scholar]
  3. Erdó S. L. Identification of GABA receptor binding sites in rat and rabbit uterus. Biochem Biophys Res Commun. 1984 Nov 30;125(1):18–24. doi: 10.1016/s0006-291x(84)80327-7. [DOI] [PubMed] [Google Scholar]
  4. Erdö S. L., Lapis E. Bicuculline-sensitive GABA receptors in rat ovary. Eur J Pharmacol. 1982 Nov 19;85(2):243–246. doi: 10.1016/0014-2999(82)90475-7. [DOI] [PubMed] [Google Scholar]
  5. Erdö S. L., Lapis E. Presence of GABA receptors in rat oviduct. Neurosci Lett. 1982 Dec 13;33(3):275–279. doi: 10.1016/0304-3940(82)90384-6. [DOI] [PubMed] [Google Scholar]
  6. Erdö S. L., László A. High specific gamma-aminobutyric acid binding to membranes of the human ovary. J Neurochem. 1984 May;42(5):1464–1467. doi: 10.1111/j.1471-4159.1984.tb02810.x. [DOI] [PubMed] [Google Scholar]
  7. Erdö S. L., László A., Kiss B., Zsolnai B. Presence of gamma-aminobutyric acid and its specific receptor binding sites in the human term placenta. Gynecol Obstet Invest. 1985;20(4):199–203. doi: 10.1159/000298994. [DOI] [PubMed] [Google Scholar]
  8. Erdö S. L., László A., Szporny L., Zsolnai B. High density of specific GABA binding sites in the human fallopian tube. Neurosci Lett. 1983 Dec 2;42(2):155–160. doi: 10.1016/0304-3940(83)90399-3. [DOI] [PubMed] [Google Scholar]
  9. Furusawa S., Ovary Z. Heteroclitic antibodies: differences in fine specificities between monoclonal antibodies directed against dinitrophenyl and trinitrophenyl haptens. Int Arch Allergy Appl Immunol. 1988;85(2):238–243. doi: 10.1159/000234509. [DOI] [PubMed] [Google Scholar]
  10. Kataoka Y., Gutman Y., Guidotti A., Panula P., Wroblewski J., Cosenza-Murphy D., Wu J. Y., Costa E. Intrinsic GABAergic system of adrenal chromaffin cells. Proc Natl Acad Sci U S A. 1984 May;81(10):3218–3222. doi: 10.1073/pnas.81.10.3218. [DOI] [PMC free article] [PubMed] [Google Scholar]
  11. Krause D. N., Wong E., Degener P., Roberts E. GABA receptors in bovine cerebral blood vessels: binding studies with [3H]muscimol. Brain Res. 1980 Mar 3;185(1):51–57. doi: 10.1016/0006-8993(80)90669-1. [DOI] [PubMed] [Google Scholar]
  12. Kusunoki M., Taniyama K., Tanaka C. Neuronal GABA release and GABA inhibition of ACh release in guinea pig urinary bladder. Am J Physiol. 1984 Apr;246(4 Pt 2):R502–R509. doi: 10.1152/ajpregu.1984.246.4.R502. [DOI] [PubMed] [Google Scholar]
  13. LOWRY O. H., ROSEBROUGH N. J., FARR A. L., RANDALL R. J. Protein measurement with the Folin phenol reagent. J Biol Chem. 1951 Nov;193(1):265–275. [PubMed] [Google Scholar]
  14. Maggi C. A., Santicioli P., Meli A. Dual effect of GABA on the contractile activity of the guinea-pig isolated urinary bladder. J Auton Pharmacol. 1985 Jun;5(2):131–141. doi: 10.1111/j.1474-8673.1985.tb00114.x. [DOI] [PubMed] [Google Scholar]
  15. Maggi C. A., Santicioli P., Meli A. GABAA and GABAB receptors in detrusor strips from guinea-pig bladder dome. J Auton Pharmacol. 1985 Mar;5(1):55–64. doi: 10.1111/j.1474-8673.1985.tb00565.x. [DOI] [PubMed] [Google Scholar]
  16. Martinez P., Gimenez A., Castro E., Oset-Gasque M. J., Cañadas S., González M. P. GABA binding in bovine adrenal medulla membranes is sensitive to baclofen. Comp Biochem Physiol C. 1987;88(1):155–157. doi: 10.1016/0742-8413(87)90060-0. [DOI] [PubMed] [Google Scholar]
  17. Minuk G. Y., Bear C. E., Sarjeant E. J. Sodium-independent, bicuculline-sensitive [3H]GABA binding to isolated rat hepatocytes. Am J Physiol. 1987 May;252(5 Pt 1):G642–G647. doi: 10.1152/ajpgi.1987.252.5.G642. [DOI] [PubMed] [Google Scholar]
  18. Napoleone P., Erdö S., Amenta F. Autoradiographic localization of the GABAA receptor agonist [3H]muscimol in rat cerebral vessels. Brain Res. 1987 Oct 13;423(1-2):109–115. doi: 10.1016/0006-8993(87)90830-4. [DOI] [PubMed] [Google Scholar]
  19. Reusens-Billen B., Pirlot X., Remacle C., Hoet J. J., de Gasparo M. Localization of GABA high-affinity binding sites in the pancreas of neonatal rat. Cell Tissue Res. 1984;235(3):503–508. doi: 10.1007/BF00226946. [DOI] [PubMed] [Google Scholar]
  20. Taniyama K., Kusunoki M., Tanaka C. gamma-aminobutyric acid inhibits motility of the isolated guinea-pig urinary bladder. Eur J Pharmacol. 1983 Apr 22;89(1-2):163–166. doi: 10.1016/0014-2999(83)90623-4. [DOI] [PubMed] [Google Scholar]

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

RESOURCES