These tools will no longer be maintained as of December 31, 2024. Archived website can be found here. PubMed4Hh GitHub repository can be found here. Contact NLM Customer Service if you have questions.


Pubmed for Handhelds

PUBMED FOR HANDHELDS

Search MEDLINE/PubMed

  • Title: Characteristics of [3H]5-hydroxytryptamine binding to iris-ciliary body tissue of the rabbit.
    Author: Chidlow G, De Santis LM, Sharif NA, Osborne NN.
    Journal: Invest Ophthalmol Vis Sci; 1995 Oct; 36(11):2238-45. PubMed ID: 7558717.
    Abstract:
    PURPOSE: This study sought to identify, characterize, and localize subtypes of 5-hydroxytryptamine (HT) receptors in rabbit iris-ciliary body. METHODS: Radioligand binding assays were performed with [3H]5-hydroxytryptamine on membranes prepared from rabbit iris-ciliary bodies and on tissue sections subsequently developed by autoradiography. RESULTS: [3H]5-HT appeared to bind to a single population of receptors in membrane preparations of rabbit iris-ciliary body. The apparent affinity of the ligand (KD) was 2.19 nM, and the density of binding sites was 58.3 fmol/mg protein. Binding of [3H] 5-HT exhibited guanosine-5-triphosphate sensitivity. Competitive inhibition experiments were performed to differentiate between 5-HT receptor subtypes. A relative potency order of 5-CT > 5-HT = 8-OH-DPAT > ipsapirone > RU24969 > sumatriptan > ritanserin > ketanserin was demonstrated. The apparent inhibitory constants for the ligands tested fit with the profile expected of binding to 5-HT1A receptors. Inhibition studies with [3H] 5-HT plus 100 nM 8-OH-DPAT (which inhibits binding to 5-HT1A receptors only) representing total binding, indicated that no further displacement occurred when ligands preferentially selective for 5-HT1B, 5-HT1D alpha,1D beta, or 5-HT2C were tested. Total binding of [3H] 5-HT in tissue sections developed by autoradiography was displaced completely by 100 nM 8-OH-DPAT. Melatonin showed little affinity for the [3H] 5-HT binding sites. CONCLUSIONS: A population of 5-HT1A receptors is present in rabbit ciliary processes. There is no evidence to suggest the presence of 5-HT1D alpha, 5-HT1D beta, 5-HT2B, or 5-HT2C receptors in the iris-ciliary body.
    [Abstract] [Full Text] [Related] [New Search]