Ocular hypotensive activity of prostaglandin F2 alpha (PGF2 alpha) analogs with neutral substituents at position 1 is predicted by the isolated cat iris sphincter smooth muscle preparation but not Ca+ signalling in Swiss 3T3 cells. - Burk RM; Woodward DF; Krauss AH; Chen J; Protzmann CE; Williams LS; Chan MF (Advances in experimental medicine and biology, 2002)