The Selective 5-HT1BReceptor Inverse Agonist 1‘-Methyl-5-[[2‘-methyl-4‘- (5-methyl-1,2,4-oxadiazol-3-yl)biphenyl-4-yl]carbonyl]-2,3,6,7-tetrahydro- spiro[furo[2,3-f]indole-3,4‘-piperidine] (SB-224289) Potently Blocks Terminal 5-HT Autoreceptor Function Both in Vitro and in Vivo