Neuroanatomy
Faculty of Medicine

Research program

Our research focuses on two subjects: First, we try to unravel the molecular and functional design of electrical synapses (gap junctions) in the central nervous system (CNS). In order to achieve a better insight into the function of electrotonic coupling via gap junctions we

I) try to clone the channel forming proteins from diverse brain areas, including the retina, which show a high incidence of coupling,

II) study their localization by light and electron microscopical immunocytochemistry and

III) develop functional mutations in tissue cultures and animal models. The latter approach will help us to understand the communicative properties of electrical synapses in neuronal networks.

A better knowledge of the function of gap junctions in normal brain tissue will allow us to understand the contribution of electrical synapses to diseases of the nervous system in which interneuronal signalling is afflicted; i.e. epilepsia, Parkinsonism, and defects of memory storage. Since glial cells also show a high incidence of gap junction coupling we expect information on pathological mechanisms of the brain in which glial cells are involved; i.e. brain edema and demyelinating diseases.

The second topic of our research is the blood-brain-barrier (BBB). The BBB constitutes a structural and metabolic barrier between the intravascular compartment of cerebral blood vessels and the parenchyma of the brain. The structural constituents of the BBB are provided by interendothelial tight junctions and a low rate of transcytosis. Specific sets of transporter, receptors, and enzymes represent the metabolic component. Thus, the barrier by controlling the exchange between the blood and the brain tissue, creates the specific environment necessary for proper brain functioning. The morphogenetic mechanisms which guide the development of the BBB are essentially unknown. We are currently trying to establish tissue culture systems in which the development of the BBB can be mimicked. Such in vitro systems are essential to elucidate the molecular background of BBB maturation and malfunctioning.