ISSN:
1432-1955
Keywords:
Key words Ivermectin
;
Nematodes
;
GABA receptor
;
Trichinella spiralis
Source:
Springer Online Journal Archives 1860-2000
Topics:
Biology
,
Medicine
Notes:
Abstract The value of the γ-aminobutyric acid (GABA) receptor of nematodes as a target for ivermectin's mode of action remains unclear. Using binding assays, we examined extracts from Trichinella spiralis muscle larvae for the presence of [3H]-ivermectin and [3H]-GABA binding sites. Tissue preparations displayed affinity binding sites for [3H]-ivermectin with a dissociation constant (K d) of 83 nM and a receptor density (Bmax) of 145 fmol/mg protein. We also identified a specific [3H]-GABA binding activity with a K d of 1.2 μM and a Bmax of 4.78 pmol/mg protein. In competition studies, ivermectin was found to be a competitive inhibitor of specific [3H]-GABA binding activity with an inhibition constant (K i) of 3.39 nM, suggesting that GABA receptors could be implicated in the mechanism of action of ivermectin in nematodes.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/s004360050555
