Interstitial volume changes during spreading depression (SD) and SD-like hypoxic depolarization in hippocampal tissue slices.
1. Relative interstitial volume (ISV) was estimated from the concentration changes of iontophoretically administered tetramethyl- and tetraethylammonium (TMA+ and TEA+). Spreading depression (SD) was provoked by high K+, and hypoxic SD-like depolarization (HSD) was induced by withdrawing oxygen. 2. Probe ion concentrations increased dramatically and about equally during SD and HSD, except that in a few hypoxic trials signals became transiently smaller than control. Interstitial volume appeared to decrease on the average by approximately 70%. 3. The ISV that remains patent in CA1 region at the height of SD is < 4% of total tissue volume. Probe ions may occasionally have passed through cell membranes for a short time during hypoxic SD.
Jing
J
J
Department of Cell Biology, Duke University Medical Center, Durham, North Carolina 27710.
Aitken
P G
PG
Somjen
G G
GG
D000818:Animals; D015687:Cell Hypoxia / Q000502:physiology*; D013181:Cortical Spreading Depression / Q000502:physiology*; D046508:Culture Techniques; D005110:Extracellular Space / Q000502:physiology*; D006624:Hippocampus / Q000502:physiology*; D007473:Ion Channels / Q000502:physiology; D008564:Membrane Potentials / Q000502:physiology; D011188:Potassium / Q000502:physiology; D051381:Rats; D009435:Synaptic Transmission / Q000502:physiology*
D007473:Ion Channels; D011188:Potassium