two radioligands , 125i-labeled substance p ( 125i-sp ) and 125i-labeled substance k ( 125i-sk ) , were used to characterize the kinetics and stoichiometry of binding of mammalian tachykinins [ substance p ( sp ) , substance k ( sk ) , and neuromedin k ( nk ) ] to smooth muscle cells isolated from the longitudinal muscle layer of guinea pig intestine .
C0039241
tachykinins
C0027847
neuromedin k