The possible role of hypoxia in the formation of axonal bulbs.
OBJECTIVE
To assess the possible role of hypoxia in the formation of axonal bulbs.


METHODS
Study material comprised sections from 28 brains showing evidence of cerebral hypoxia with no history of head injury, four with a history of head trauma but no evidence of hypoxic change, eight with a history of head trauma and hypoxic change, and four from control brains originally described as "diffuse axonal injury." These were subjected to microwave antigen retrieval and immunohistochemistry using monoclonal antibodies to beta amyloid precursor protein (beta APP), glial fibrillary acid protein (GFAP), and CD68-PGM1.


RESULTS
Positive staining for beta APP was seen in all four controls, all four cases of head injury only, seven of eight cases of head injury and hypoxic changes, and 12 of 28 cases of hypoxia without history of head injury; 22 of 25 cases who had been ventilated showed positive staining. The majority of cases showed evidence of cerebral swelling.


CONCLUSIONS
Axonal bulbs staining positively for beta APP may occur in the presence of hypoxia and in the absence of head injury. The role of hypoxia, raised intracranial pressure, oedema, shift effects, and ventilatory support in the formation of axonal bulbs is discussed. The presence of axonal bulbs cannot necessarily be attributed to shearing forces alone.
Kaur
B
B
Department of Forensic Pathology, University of Sheffield, UK.
Rutty
G N
GN
Timperley
W R
WR
D000328:Adult; D000368:Aged; D016564:Amyloid beta-Protein Precursor / Q000032:analysis*; D015703:Antigens, CD / Q000032:analysis; D015214:Antigens, Differentiation, Myelomonocytic / Q000032:analysis; D001369:Axons / Q000473:pathology*; D015415:Biomarkers / Q000032:analysis; D002648:Child; D002675:Child, Preschool; D006259:Craniocerebral Trauma / Q000150:complications* / Q000473:pathology; D017809:Fatal Outcome; D005260:Female; D005904:Glial Fibrillary Acidic Protein / Q000032:analysis; D006801:Humans; D002534:Hypoxia, Brain / Q000209:etiology* / Q000473:pathology; D007150:Immunohistochemistry; D007223:Infant; D007231:Infant, Newborn; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D012189:Retrospective Studies; D000097382:CD68 Molecule
D016564:Amyloid beta-Protein Precursor; D015703:Antigens, CD; D015214:Antigens, Differentiation, Myelomonocytic; D015415:Biomarkers; D005904:Glial Fibrillary Acidic Protein; C067980:CD68 antigen, human; D000097382:CD68 Molecule