Fig. 2.
Sensitivity of PA and MCA VSM to calcium in S. aureus α-toxin permeabilized vessels. A and B: graphs showing constriction of permeabilized PAs (●) and MCAs (◻), respectively, to increasing concentrations of calcium. Both vessel types constricted in response to increased extracellular calcium. C: graph showing the sensitivity to calcium of PAs and MCAs. There was no difference in the sensitivity of the contractile apparatus to calcium.