Inhibitory effect of 2,4-dihydroxyphenylacetylasparagine, a common moiety of spider toxin, on glutamate binding to rat brain synaptic membranes.
2,4-Dihydroxyphenylacetylasparagine (2,4-DHPA-ASN), a common moiety of molecules of spider toxins, was shown to inhibit L-[3H]glutamic acid binding to rat brain synaptic membranes in a dose-dependent manner. The inhibitory effect of 2,4-DHPA-ASN was almost the same as that of intact spider toxin isolated from Nephila clavata, but significantly higher than that of 2,4-dihydroxyphenylacetic acid (2,4-DHPA). In addition, neither 2,4-dihydroxybenzoic acid nor the isomers of 2,4-DHPA suppressed the glutamate binding. These results suggested that 2,4-DHPA might be the functional part and asparagine in the molecules of spider toxins seemed to cause increasing affinity toward the recognition site of glutamate binding.
Pan-Hou
H
H
Faculty of Pharmaceutical Sciences, Setsunan University, Osaka, Japan.
Suda
Y
Y
Sumi
M
M
Yoshioka
M
M
Kawai
N
N
D000818:Animals; D001180:Arthropod Venoms / Q000494:pharmacology*; D001216:Asparagine / Q000031:analogs & derivatives* / Q000494:pharmacology; D001921:Brain / Q000378:metabolism*; D005971:Glutamates / Q000378:metabolism*; D007700:Kinetics; D008297:Male; D051381:Rats; D011919:Rats, Inbred Strains; D017470:Receptors, Glutamate; D017981:Receptors, Neurotransmitter / Q000187:drug effects / Q000378:metabolism*; D013111:Spider Venoms / Q000494:pharmacology*; D013570:Synaptic Membranes / Q000187:drug effects / Q000378:metabolism*
D001180:Arthropod Venoms; D005971:Glutamates; D017470:Receptors, Glutamate; D017981:Receptors, Neurotransmitter; D013111:Spider Venoms; C054470:2,4-dihydroxyphenylacetylasparagine; D001216:Asparagine