Macroscopic enzyme histochemistry in myocardial infarction: use of coenzyme, cyanide, and phenazine methosulphate
Abstract:
Transversely sectioned human heart slices, obtained at necropsy from normal subjects and from cases of recent myocardial infarction, were stained with the nitroblue tetrazolium (NBT) dehydrogenase macroreaction for the gross identification of recent myocardial infarction. The addition of nicotinamide adenine dinucleotide (NAD) to the incubating medium greatly improved the sensitivity of the method, while addition of cyanide caused just a modest improvement. Addition of the electron transfer mediator phenazine methosulphate (PMS) resulted in false non-selective staining and obscured areas of recent myocardial damage.
Insights
This study enhances nitroblue tetrazolium (NBT) staining for identifying recent myocardial infarction in human heart slices. Adding nicotinamide adenine dinucleotide (NAD) significantly improves NBT test sensitivity for diagnosing heart attacks.
Area of Science:
- Cardiovascular Pathology
- Biochemical Staining Techniques
Background:
- Gross identification of recent myocardial infarction is crucial for diagnosis.
- Existing staining methods may lack sufficient sensitivity or specificity.
Purpose of the Study:
- To optimize the nitroblue tetrazolium (NBT) dehydrogenase macroreaction for gross identification of recent myocardial infarction.
- To evaluate the effects of additives on NBT staining sensitivity and specificity.
Main Methods:
- Human heart slices from necropsies (normal and myocardial infarction cases) were used.
- The nitroblue tetrazolium (NBT) dehydrogenase macroreaction was applied.
- Additives including nicotinamide adenine dinucleotide (NAD), cyanide, and phenazine methosulphate (PMS) were tested.
Main Results:
- Addition of nicotinamide adenine dinucleotide (NAD) significantly enhanced the sensitivity of the NBT staining method.
- Cyanide provided only a modest improvement in staining sensitivity.
- Phenazine methosulphate (PMS) led to non-selective staining, obscuring myocardial damage.
Conclusions:
- The optimized NBT macroreaction, particularly with NAD supplementation, offers improved gross identification of recent myocardial infarction.
- This method provides a more sensitive diagnostic tool for acute cardiac events.
- Avoidance of PMS is recommended to prevent false positives and maintain diagnostic clarity.
