'Mad Cow' Detectable Earlier in Autonomic Nervous System
(HealthDay News) – Prions responsible for bovine spongiform encephalopathy (BSE) are detectable in the autonomic nervous system before the central nervous system.
Martin Kaatz, DVM, from the Friedrich-Loeffler-Institute in Greifswald-Isle of Riems, Germany, and colleagues examined the route of infectious prions from the gut to the central nervous system in preclinical and clinical BSE-infected calves. Tissue samples were collected from the gut, central nervous system, and autonomic nervous system from animals that had been infected with BSE 16–44 months earlier.
The researchers found that pathological prions were present in the follicles and/or enteric nervous system of the distal ileum in almost all animals. Prions were also found in the sympathetic nervous system 16 months post-infection and the parasympathetic nervous system 20 months post-infection. The brain stem showed signs of infection at 24 months post-infection but prion accumulation was not observed until 28 months post-infection.
"In summary, our results decipher the centripetal spread of BSE prions along the autonomic nervous system to the central nervous system, starting already halfway in the incubation time," Kaatz and colleagues conclude.