based on pec50-values ( the negative log of the 50 % effective concentration ) for each imidazoline , a rank order of potency of p-aminoclonidine greater than oxymetazoline greater than or equal to clonidine greater than naphazoline greater than phentolamine was obtained in the rabbit vas deferens and an order of p-aminoclonidine greater than clonidine greater than naphazoline greater than oxymetazoline was obtained in the guinea pig ileum .
C1449836
imidazoline
C0030071
oxymetazoline