Impulses of variable amplitude recorded from cell-attached patches on small hippocampal neurons.
Small cultured neurons from embryonic rat hippocampus were investigated with the cell-attached configuration of the patch-clamp technique. The currents associated with spontaneous cellular impulse generation were studied. The positive peak current amplitudes varied by a factor larger than 2.5 for 11 of 12 cells quantitatively investigated, suggesting underlying action potentials of variable amplitude. A simple RC-network was found to describe the properties of the patch membrane, and was used to calculate the underlying potential time course. The action potentials computed showed a considerable variation in amplitude. The results suggest that the impulse variability previously analysed with the whole-cell technique was not caused by dialysis of the cell interior.
Johansson
S
S
Nobel Institute for Neurophysiology, Karolinska Institutet, Stockholm, Sweden.
Arhem
P
P
D000200:Action Potentials / Q000502:physiology; D000818:Animals; D002478:Cells, Cultured; D006624:Hippocampus / Q000166:cytology / Q000196:embryology / Q000502:physiology*; D009474:Neurons / Q000502:physiology*; D051381:Rats; D013997:Time Factors