Presynaptic block of transmission in the insect cns by mono- and di-galactosyl analogues of vespulakinin 1, a wasp (Paravespula maculifrons) venom neurotoxin.
1. The pharmacological properties of four synthetic analogues of the wasp neurotoxin, Vespulakinin 1, were studied using a cascade of mammalian smooth muscle preparations and the synaptic transmission from the cockroach cercal nerves to a giant interneuron. 2. All analogues have an extremely slow bradykinin-like effect on the smooth muscles. The carbohydrate-free and the two mono-glycosylated analogues are about equally active with bradykinin. 3. The double glycosylated derivative is about 5 times more potent than bradykinin. 4. All analogues have two different effects on synaptic transmission in the insect CNS--at first a direct and reversible block of excitatory nicotinic transmission with a concurrent activation of the inhibitory GABA-ergic system and, secondly, a delayed irreversible block of the transmission, comparable to the block described earlier for bradykinin and Thr6-bradykinin. 5. For the synaptic transmission in the insect CNS the double glycosylated kinin is about 5 times more potent than bradykinin.
Piek
T
T
Department of Pharmacology, University of Amsterdam, The Netherlands.
Hue
B
B
Le Corronc
H
H
Mantel
P
P
Gobbo
M
M
Rocchi
R
R
D000595:Amino Acid Sequence; D000818:Animals; D001920:Bradykinin / Q000031:analogs & derivatives / Q000494:pharmacology; D002240:Carbohydrate Sequence; D002490:Central Nervous System / Q000187:drug effects; D003058:Cockroaches; D006031:Glycosylation; D006168:Guinea Pigs; D066298:In Vitro Techniques; D008969:Molecular Sequence Data; D009130:Muscle, Smooth / Q000187:drug effects; D051381:Rats; D013569:Synapses / Q000187:drug effects*; D009435:Synaptic Transmission / Q000187:drug effects*; D014862:Wasp Venoms / Q000494:pharmacology*
D014862:Wasp Venoms; C083129:vespulakinin 1, galactosylThr(3)-; C083130:vespulakinin 1, galactosylThr(3)-galactosylThr(4)-; C062689:bradykinin, Thr(6)-; D001920:Bradykinin