5-HT1A receptor-mediated activation of high-affinity GTPase in rat hippocampal membranes.
GTP hydrolyzing activity was assayed by measuring the amount of 32P(i) released from 0.3 microM [gamma-32P]GTP in the membranes prepared from rat brain. 5-Hydroxytryptamine (5-HT) stimulated the high-affinity GTPase activity in hippocampus, but not in striatum, in a concentration-dependent manner with an EC50 value of 18 nM and maximal percent stimulation of 13.9%. This response was mimicked by (+/-)-8-hydroxy-2-(di-n-propylamino)tetralin [(+/-)-8-OH-DPAT], but not by (+/-)-1-(2,5-dimethoxy-4-iodophyenyl)-2-aminopropane [(+/-)-DOI]. These results suggest that 5-HT-stimulated high-affinity GTPase activity of the GTP-binding protein(s) is mediated via 5-HT1A receptor subtype in the rat hippocampus.
Odagaki
Y
Y
Department of Neuroscience, Karolinska Institute, Stockholm, Sweden.
Fuxe
K
K
D017371:8-Hydroxy-2-(di-n-propylamino)tetralin / Q000494:pharmacology; D000818:Animals; D004305:Dose-Response Relationship, Drug; D004789:Enzyme Activation; D020558:GTP Phosphohydrolases / Q000378:metabolism*; D019204:GTP-Binding Proteins / Q000378:metabolism; D006160:Guanosine Triphosphate / Q000494:pharmacology; D006624:Hippocampus / Q000201:enzymology*; D066298:In Vitro Techniques; D008297:Male; D051381:Rats; D017207:Rats, Sprague-Dawley; D011985:Receptors, Serotonin / Q000502:physiology*; D012701:Serotonin / Q000494:pharmacology
D011985:Receptors, Serotonin; D012701:Serotonin; D017371:8-Hydroxy-2-(di-n-propylamino)tetralin; D006160:Guanosine Triphosphate; D020558:GTP Phosphohydrolases; D019204:GTP-Binding Proteins