Animal 68 Rats Support, Non-U.S. Gov't animal rat 66 article 62 metabolism 52 animal experiment 30 Male 28 male 28 rat strain 28 Rats, Inbred Strains 26 Female 24 female 24 radioisotope 24 In Vitro 22 drug effect 22 in vitro study 22 nonhuman 22 Norepinephrine 18 endocrine system 18 noradrenalin 18 Kinetics 14 enzymology 14 kinetics 14 physiology 14 Dinoprost 12 Liver 12 Prostaglandins E 12 Prostaglandins F 12