their respective orders of potency , 4-ap = 3,4-diap much greater than 3-ap , and tetrabutylammonium ( tba ) greater than tetraethylammonium much greater than tetramethylammonium , paralleled their abilities to block k+ channels , ( 2 ) the order of potency of pcp and its analogs for binding to the pcp receptor , tcp greater than pce greater than m-amino-pcp greater than pcp greater than pcpy greater than m-nitro-pcp , paralleled their rank order for blocking brain k+ channels , and ( 3 ) the stereospecific displacement of [ 3h ] pcp binding by the isomers of the `` '' sigma '' '' ligands , ( + ) n-allyl-normetazocine ( nanm ) greater than ( - ) nanm , and ( - ) cyclazocine greater than ( + ) cyclazocine , and of the dioxolanes , dexoxadrol much greater than levoxadrol , paralleled their abilities to block brain k+ channels .
C0233660
blocking
C0006104
bra