Fig. 5. Typical results of the mechanical test on the dermis in Ca²⁺-free artificial seawater (Ca²⁺-free ASW). (A) Mechanical test on a control dermis. The stiffness rapidly decreased at the very start of the dynamic test. Addition of 100 µl Ca²⁺-free ASW (downward arrow) did not cause a change in stiffness. (B) Effect of 100 µl Ca²⁺-free ASW containing H-tensilin (final concentration; 1 µg ml^–1) on the stiffness of the dermis. A rapid decrease in stiffness was observed at the start of the mechanical test, as in A. Application of H-tensilin (downward arrow) caused an increase in stiffness, and washing with Ca²⁺-free ASW (upward arrow) caused a decrease in stiffening.