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DOI: 10.1055/s-2001-919055
© Karl Demeter Verlag im Georg Thieme Verlag Stuttgart · New York
Influence of albumin dialysis (MARS) on neuronal network activity in vitro - early results
Publication History
Publication Date:
07 October 2005 (online)
Introduction
In liver failure, toxic substances accumulate in the body that may disturb the function of the central nervous system. This is generally thought to be the cause of hepatic encephalopathy and coma. A new dialysis treatment based on albumin dialysis (Molecular Adsorbents Re-circulating-System, MARS) was developed to remove accumulating toxins from patients in liver failure [1]. Clinical studies have shown that MARS treatments can ameliorate hepatic encephalopathy of patients in severe liver failure [2].
The mechanisms how accumulating substances may lead to cerebral dysfunctions and hepatic coma are not clearly understood, primarily because of the difficulty of obtaining conclusive evidence from in vivo models. Furthermore, the degree of hepatic encephalopathy does not always correlate with plasma concentrations of potential toxins. Spontaneously electrically active neuronal networks cultured on microelectrode plates may be a means to study the effects of potential toxins on neuronal function under defined conditions in vitro. Previous work has demonstrated the specificity and reversibility of network responses to neurotransmitters and a variety of neuroactive compounds. We investigated the reaction of these networks to ultrafiltrates of human blood plasma to determine if toxins in liver failure can be detected with this system, and if so, to evaluate the effect of MARS treatments on the network responses. Hypotheses: 1) There is a difference between neuronal responses to normal human plasma and plasma from patients in hepatic coma. 2) MARS treatments diminish effects of patient samples on neuronal activity.
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Jan Loock
Department of Internal Medicine University of Rostock, Germany
Email: Jloock@freenet.de