Early myocardial ischaemia: evaluation of the histochemical haematoxylin-basic fuchsin-picric acid (HBFP) staining technique.

A series of experiments, carried out to evaluate the histochemical method for the morphological diagnosis of early stages of myocardial ischaemis (HBFP) is reported. The experiments were performed on dog hearts in which ischaemia was induced by coronary artery ligation for different periods of time. The original procedure or modifications of the HBFP-technique, including different staining, rinsing, and differentiation times, the use of different commercial brands of chemicals and preparatory changes of routine histological procedures such as fixation, embedding, cutting, and mounting, did not give satisfactory results. False positive and negative staining was frequent. Very equivocal results were obtained on serial sections of ischaemic tissue samples. Therefore this method was regarded as unreliable and non-reproducible.