Figure 6.

Inactivation of chitin fragments in cell suspensions before and after desensitization. Inactivation was tested in suspensions without pretreatment (○, ⋄) or 60 min after pretreatment with 1 nm CH4 (•, ♦). At time 0, CH4 (10 nm) was added to cell suspensions or the corresponding culture medium freed of cells by filtration. Samples were taken at intervals, and serial dilutions were assayed for the induction of the alkalinization response. Equivalents of CH4 in the samples were determined from a standard curve obtained with untreated CH4. ○, Cell suspension without pretreatment; ⋄, cell-free medium of control cells; •, cell suspension pretreated with 1 nm CH4; ♦, cell-free medium from pretreated cells.