Biological Activity
al 34662 is a potent 5-ht2 receptor agonist.serotonin (5-hydroxytryptamine; 5-ht) is a major neurotransmitter in the central nervous system (cns) of mammals and has welldocumented physiological functions in numerous cells, tissues, and organs.
in vitro
al-34662 exhibited a high affinity for the rat and human 5-ht2 receptor and for cloned human 5-ht2a-c receptors. al-34662 stimulated phosphoinositide turnover in human ciliary muscle and in human trabecular meshwork cells. al-34662 also mobilized intracellular ca2+ in h-cm and h-tm cells, being a full agonist like 5-ht itself. al-34662's effects in the h-cm cells were potently antagonized by 5-ht2a-antagonist m-100907, but weakly by 5-ht2b-antagonist, 5-ht2b/c- antagonist and 5-ht2c antagonist. moreover, it was found that the (r)-enantiomer (al-34707) and the racemate (al-34497) were less potent and/or efficacious than al-34662 in all of these assays [1].
in vivo
al-34662 caused relatively minimal ocular discomfort and hyperemia in rabbit and guinea pig eyes. it efficaciously lowered intraocular pressure in the conscious ocular hypertensive monkey eyes [1].
IC 50
0.8-1.5 nm for rat and human 5-ht2 receptor
References
[1] sharif na, mclaughlin ma, kelly cr. al-34662: a potent, selective, and efficacious ocular hypotensive serotonin-2 receptor agonist. j ocul pharmacol ther. 2007 feb;23(1):1-13.
