Reduction of voltage-dependent calcium currents in mumps virus-infected cultures of rat hippocampal neurons.
The effects of a mumps virus infection on functional properties of embryonic hippocampal neurons in culture were analysed with special emphasis on voltage-dependent Ca2+ channels. Cultures with higher or lower density of glial cells (not treated or treated with mitotic inhibitor, respectively) were infected with the relatively non-cytolytic RW strain of mumps virus and currents were recorded from neurons using whole cell voltage clamp. More than 65% of neurons and glial cells contained viral antigens 1-2 days post infection (p.i.). Glial cells remained infected 6-7 days p.i., while the ratio of infected versus uninfected neurons, especially in cultures with higher glial cell density, was reduced. In both infected and uninfected cultures the somal voltage-dependent Ca2+ currents were stronger in cultures with a higher glial cell density, which indicates that these currents are influenced by glial cells. Introduction of the virus into cultures caused a selective decrease in inward Ca2+ currents, which was most marked at days 6-7 p.i., and which included both infected and unifected neurons. Spontaneous synaptic currents and other ion channel conductances appeared normal in the infected cultures. Dantrolene, which inhibits release of Ca2+ from intracellular stores, decreased the neurons that died during the infection. Taken together the results show that a mumps viral infection can selectively alter the number of function of somal voltage dependent Ca2+ channels in immature hippocampal neurons and that this may reflect a disturbed glia-nerve cell interaction.
Owe-Larsson
B
B
Department of Neuroscience, Karolinska Institutet, Stockholm, Sweden.
Andersson
T
T
Kristensson
K
K
Hill
R H
RH
D000200:Action Potentials / Q000187:drug effects; D000818:Animals; D002121:Calcium Channel Blockers / Q000494:pharmacology; D015220:Calcium Channels / Q000378:metabolism*; D002478:Cells, Cultured; D003620:Dantrolene / Q000494:pharmacology; D006624:Hippocampus / Q000187:drug effects / Q000196:embryology* / Q000378:metabolism / Q000821:virology; D009107:Mumps / Q000378:metabolism*; D009109:Mumps virus; D009457:Neuroglia / Q000187:drug effects / Q000378:metabolism* / Q000821:virology; D009474:Neurons / Q000187:drug effects / Q000378:metabolism* / Q000821:virology; D009543:Nifedipine / Q000494:pharmacology; D051381:Rats
D002121:Calcium Channel Blockers; D015220:Calcium Channels; D003620:Dantrolene; D009543:Nifedipine