Fig. 1.
Effect of PHE (10−5 M) on contraction and [Ca2+]i in male and female inferior vena cava (IVC). IVC segments from male (A, C, E) and female rats (B, D, F) were loaded with fura-2. The vein segments were stimulated with phenylephrine (PHE) (10−5 M), and the simultaneous changes in contraction (A, B), 340- and 380-nm fluorescence signal (C, D), and 340/380 ratio (E, F) were recorded. Cumulative time-course graphs represent means ± SE of PHE-induced contraction (G) and [Ca2+]i measurements (H) in male and female IVC (n = 5 or 6). *Measurements in female IVC are significantly different compared with corresponding measurements in male IVC (P < 0.05).