In their native state they are {TAIL ~ an antagonist} of {HEAD ~ the alpha nicotinic acetylcholine receptor} 
In their native state they are { TAIL ~ an antagonist } of { HEAD ~ the alpha nicotinic acetylcholine receptor }
OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD