[Neuroscience] problems with dissociated cells & Ca2+ current recording

[Sibylle Guggenmoos-Schreyer]

I am trying to record Ca2+ currents (whole-cell) from acutely  
dissociated hippocampal CA1 neurons (7-10 day-old rats and mice).  
However, the cells only survive a couple of minutes after having  
established the patch. I wonder if this is a dissociating or a bath  
solution problem, as I can't bubble the bath solution with carbogene  
(it becomes too acidic). I tried recording Ca currents in acute slices  
of very young rats before, and those currents were stable but very  
difficult to influence with various substances which is why I think  
the bath solution might be the cause of trouble.
So, if anyone's got either a good bath solution recipe or a  
dissociating method or any other idea - I'd be so grateful!
Sibylle