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Updated: Sep 6, 2026

The Use of Pharmacological-challenge fMRI in Pre-clinical Research: Application to the 5-HT System
Published on: April 25, 2012
The alpha 2-adrenoceptor antagonist SK&F 104078 has high affinity for 5-HT1A and 5-HT2 receptors
A T Kilpatrick1, C M Brown, A C MacKinnon
1Department of Pharmacology, Syntex Research Centre, Riccarton, Edinburgh, U.K.
Abstract:
The affinity of SK&F 104078, a putative selective postjunctional alpha 2-adrenoceptor antagonist, was determined at 5-HT1A and 5-HT2 receptors in rat brain. SK&F 104078 had moderate affinity towards alpha 2-adrenoceptors (pKi 6.7) but displayed higher affinity at 5-HT1A (pKi 8.1) and 5-HT2 (pKi 7.6) receptors. If SK&F 104078 is used in functional studies to define heterogeneity within of alpha 2-adrenoceptors, care must be taken to define the role of 5-HT1A and 5-HT2 receptors in the response being measured.
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