Abstract: Objective To investigate the relationship between heroin spongiform leucoencephalopathy and respiratory chain
complex I deficiency. Methods The activity of respiratory chain complex I in peripheral white blood cell mitochondria was
compared between 36 cases of heroin spongiform leucoencephalopathy and 36 healthy subjects using enzyme-linked
immunosorbent assay (ELISA). Results The activity of respiratory chain complex I was 5.6±2.4 U/ml in patients with heroin
spongiform leucoencephalopathy, signficiantly higher than that in the normal subjects (4.2 ± 2.1 U/ml, t=2.634, P<0.05).
Conclusion In patients with heroin spongiform leucoencephalopathy, mitochondrial dysfunction results in energy metabolism
disorder to cause extensive demyelination of the cerebral white matter. Respiratory chain complex I deficiency of the
mitochondria plays a significant role in the pathogenesis of heroin spongiform leucoencephalopathy.