Fig. 1.

Oxytocin-induced contraction. Uterine strips from virgin, mid-Preg (12d-Preg), and late-Preg rats (19d-Preg) were incubated in normal Krebs solution. The uterine strips were stimulated with oxytocin (10⁻¹¹ to 10⁻⁷ M) and the contractile response was recorded (A). At the end of the experiment, the uterine tissue weight was recorded (C). Cumulative contraction data from uterine strips of different rats were presented in grams (B), grams/milligram tissue weight (D) and % of maximal contraction (E). Preg, pregnant; 12d, 12 days. Data represent means ± SE, n = 4 to 6. *Significantly different (P < 0.05).