Retention Mechanism of Imidazoles in Connective Tissue. II. Activation of Imidazoles in Cupro-ascorbate System for Irreversible Binding Formation with Aortic Tissue in Vitro

In order to obtain an insight into the retention mechanism of drugs with imidazole moiety in the connective tissue, the in vitro characteristics of the interaction between 14C-labeled imidazoles (imidazole and its 2-methyl derivative) and slices of dog aorta were studied. We found that cupro-ascorbate-catalyzed oxidative reactions for the imidazoles led to their irreversible binding with connective tissue, and that, from a study using protein modifiers, the aldehydic function intrinsic to the tissue protein was involved in the binding formation. This characteristic in vitro was observed under physiological conditions, hence it can be extrapolated to the in vivo situation and could also give a clue to the nature of the retention of imidazole-containing drugs in connective tissue.