the antibiotic bacitracin ( 5 x 10 ( -5 ) -4 x 10 ( -4 ) m ) increase the inhibition of the contractile response caused by both enkephalin release and direct application of met-enkephalin 5 x 10 ( -7 ) m in the longitudinal muscle strip preparation from guinea-pig ileum .
C0014298
enkephalin
C0014295
met-enkephalin