{'fraction_non_alphanumeric': 0.026376146788990827, 'fraction_numerical': 0.005733944954128441, 'mean_word_length': 5.101398601398602, 'pattern_counts': {'":': 0, '<': 0, '<?xml version=': 0, '>': 0, 'https://': 0, 'lorem ipsum': 0, 'www.': 0, 'xml': 0}, 'pii_count': 0, 'substrings_counts': 0, 'word_list_counts': {'cursed_substrings.json': 0, 'profanity_word_list.json': 0, 'sexual_word_list.json': 0, 'zh_pornsignals.json': 0}}
Poster Sessions AP04: Astrocytes

We are seeking to define the types of astroglial-like cells in a defined region of the CNS, namely the CA1 region of the hippocampus. Using a freshly isolated cell preparation we have found two types of GFAP immunopositive cells (GFAP(+)) that show two very different types of electrophysiological phenotypes. One type we term variably rectifying astrocytes (VRAs) that are similar to the classical astrocyte, exhibiting both inward and outward K currents. VRAs also possess glutamate transporter currents. The equally numerous second type is what we call outwardly rectifying astrocytes (ORAs) that show predominantly outward voltage-sensitive Kd and Ka currents, a small inward Na + current, and no glutamate transporter currents, but strong AMPA currents. As isolated the VRAs have a mean membrane potential of )65 mV and the ORAs a more depolarized potential of )40 mV. Another numerous glial cell type that are present in our isolated cell preparations have electrophysiological phenotypes very similar to ORAs and have been referred to as complex cells. They differ morphologically from VRAs or ORAs, that both have a bushy process-bearing appearance, and have been called smooth protoplasmic astrocytes based on in situ morphology. In our preparation such cells are not GFAP(+) but do have mRNA for GFAP. They stain for the glycoprotein NG2 and therefore may correspond to what have been termed elsewhere OPCs (oligodendrocyte precursor cells) or O2A (oligodendrocyte-type 2 astrocyte) cells. It remains unclear how all these properties, and others yet to be found, relate to the functions of these three distinct types of cells, and if they should all be termed from a functional viewpoint, astrocytes.