Representative traces showing contractile activity elicited by the tachykinins (a) SP, (b) NKA, (c) NKB, (d) [Sar9Met(O2)11]SP, (e) [Lys5MeLeu9Nle10]NKA(4–10) and (f) [MePhe7]NKB, together with their corresponding response to KPSS on myometrial preparations obtained from two nonpregnant women. Responses shown in (a)–(c) were on tissue obtained from a 41-year old woman. Responses shown in (d)–(f) were on tissue obtained from a 38-year old woman. Responses to SP, NKA and NKB are in the presence of peptidase inhibitors thiorphan (3 μM), captopril (10 μM) and bestatin (10 μM).