Complex allosteric interaction of heparin with neurokinin-1 receptors.
The effects of several heparin preparations on rat striatal neurokinin-1 receptor labelling were investigated. A low concentration of heparin dose-dependently stimulated [125I]Bolton-Hunter substance P ([125I]BH-SP) binding to rat striatal membranes. This effect was mainly due to an increase of the association velocity reflected by a decrease of the equilibrium dissociation rate constant. A higher heparin concentration inhibited specific [125I]BH-SP labelling by a negative allosteric mechanism as a result of an increase of the dissociation velocity.
Knaus
G A
GA
Neurochemistry Research Unit, University Hospital of Psychiatry, Innsbruck, Austria.
Knaus
H G
HG
Saria
A
A
D000495:Allosteric Site; D000818:Animals; D003342:Corpus Striatum / Q000187:drug effects / Q000378:metabolism*; D006493:Heparin / Q000737:chemistry / Q000378:metabolism / Q000494:pharmacology*; D008970:Molecular Weight; D051381:Rats; D018041:Receptors, Neurokinin-2; D017981:Receptors, Neurotransmitter / Q000378:metabolism*; D013373:Substance P / Q000737:chemistry / Q000378:metabolism*; D013388:Succinimides / Q000737:chemistry / Q000378:metabolism*
C043194:Bolton Hunter reagent-substance P conjugate; D018041:Receptors, Neurokinin-2; D017981:Receptors, Neurotransmitter; D013388:Succinimides; D013373:Substance P; D006493:Heparin