Agonist-directed trafficking, receptor stimulus

Agonist-Directed Trafficking of Receptor Stimulus and Serotonin Receptors... 

Agonist-Directed Trafficking of 5-HT2C Receptor Stimulus... 

Fig. 2. Agonist-directed trafficking of 5-HT2C receptor stimulus. Concentration-response curves for 5-HT2C agonists measuring AA release (PLA2-AA) and IP accumulation (PLC-PI) in CHO-1C19 cells expressing the human 5-HT2c receptor (approx 200 fmol/mg protein). Cells, in serum-free medium, were labeled with 1 pCi/mL [3H]-myo-inositol (10-25 Ci/mmol) for 24 h and with 0.1 pCi/inL [14C]-arachidonic acid (57 mCi/mmol) for 4 h at 37°C. Measurements of PLC-mediated IP accumulation and PLA2-AA release were made from the same multiwell, simultaneously, after 10 min of...

As mentioned earlier, current models of receptor function provide for receptor conformations that interconvert between inactive and active states. The agonist-directed trafficking of receptor stimulus hypothesis suggests that there are multiple active conformations of a receptor that differ in their capacity to couple/activate effector pathways. Such multistate models predict that, like agonist-stimulated responses, constitutive receptor activity and the relative efficacy of inverse agonists should also be response dependent (Fig. 6). 

Berg KA, Maayani S, Goldfarb J, Scaramellini C, Leff P, Clarke WP. Effector pathway-dependent relative efficacy at serotonin type 2A and 2C receptors evidence for agonist-directed trafficking of receptor stimulus. Mol Pharmacol 1998 54 94-104. 

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