To evaluate the significance of immunohistochemical staining of ubiquitin (heat shock protein) in the midbrain for the medico-legal diagnosis of fatal asphyxiation and drowning, we investigated forensic autopsy cases of fatal mechanical asphyxia (n = 18), manual/ligature strangulation (n = 9), hanging (n = 4), aspiration/choking (n = 5) and drowning (n = 16). These were compared to control groups (n = 30) consisting of fatalities from brainstem injury (n = 12) and acute myocardial infarction (n = 18). Ubiquitin was clearly demonstrated in the nuclei of pigmented substantia nigra neurons, showing two intranuclear staining patterns: a type of inclusion (possibly Marinesco bodies) and a diffuse staining. The diffuse staining was significantly more frequently observed in cases of drowning. The percentage of total ubiquitin positive neurons was frequently higher in strangulation (5.1-28.4%, mean 17.0%), aspiration/choking (5.3-32.0%, mean 17.6%) and drowning (7.0-34.1%, mean 19.8%), but relatively low in hanging (5.1-12.7%, mean 8.6%), brainstem injury (0-10.4%, mean 5.0%) and acute myocardial infarction (1.5-16.9%, mean 8.3%). These observations suggest that intranuclear ubiquitin immunoreactivity of the pigmented substantia nigra neurons in the midbrain was induced by a fatal severe stress on the central nervous system in asphyxiation and drowning.
- Pigmented substantia nigra neuron
ASJC Scopus subject areas
- Pathology and Forensic Medicine