Development of Voltage-Sensitive Sodium Channels in         Astrocytes
{'Code': '08090200', 'Directorate': {'Abbreviation': 'BIO', 'LongName': 'Direct For Biological Sciences'}, 'Division': {'Abbreviation': 'IOS', 'LongName': 'Division Of Integrative Organismal Systems'}}
{'SignBlockName': 'name not available', 'PO_EMAI': None, 'PO_PHON': None}
Although astrocytes constitute the major cell type in the                       mammalian central nervous system (CNS), their functional                        properties in maintaining homeostatis during neuronal activity                  have been reconsidered, with the ability to prepare homogeneous                 cell cultures.  Using these cultures, recent studies indicate                   that this previously considered electrically silent cell                        possesses voltage-sensitive channels for sodium, calcium,                       potassium and chloride.  Voltage-sensitive channels meditate                    changes in membrane permeability to selected ions in response to                a change in membrane voltage.  This project deals specifically                  with types of voltage-gated sodium channels in astrocytes.  In                  electrically excitable tissue, two distinct types of sodium                     channels have been found.  These types of voltage-gated channels                have separate binding sites for saxitoxin and tetrodotoxin.  Rat                brain astrocytes also have these types of sodium channels.  They                are present in differing proportions at early and late stages of                astrocyte maturity.  Using neurotoxin-activated 22Na+ flux,                     intracellular and whole-cell recording techniques and toxin                     binding methods, physiological and pharmacological properties of                both types of astrocyte sodium channels will be compared to                     properties in excitable membranes; the density of sodium channels               will be discovered at different stages of morphological                         differentiation; electrical excitability will be determined in                  early and late astrocyte cultures; and factors that trigger or                  retard the expression of toxin-insensitive channels and                         toxin-sensitive channels will be explored.  In addition, an                     astrocyte membrane preparation will be incorporated into planar                 lipid bilayers in order to study the biophysical characteristics                of single toxin-insensitive and toxin-sensitive sodium channels                 and to compare their properties with those from electrically                    excitable tissue.  The results of this proposal should provide a                new basis for understanding some of the complex interactions                    between neurons and glia and whether astrocyte sodium channels                  are similar to those in nerve and muscle.
{'FirstName': 'Paul', 'LastName': 'Yarowsky', 'PI_MID_INIT': 'J', 'PI_SUFX_NAME': None, 'PI_FULL_NAME': 'Paul J Yarowsky', 'EmailAddress': None, 'NSF_ID': '000397686', 'StartDate': '08/15/1987', 'EndDate': None, 'RoleCode': 'Principal Investigator'}
{'Name': 'University of Maryland at Baltimore', 'CityName': 'BALTIMORE', 'ZipCode': '212011531', 'PhoneNumber': '4107063559', 'StreetAddress': '220 ARCH ST OFC LEVEL2', 'StreetAddress2': None, 'CountryName': 'United States', 'StateName': 'Maryland', 'StateCode': 'MD', 'CONGRESSDISTRICT': '07', 'CONGRESS_DISTRICT_ORG': 'MD07', 'ORG_UEI_NUM': 'Z9CRZKD42ZT1', 'ORG_LGL_BUS_NAME': 'UNIVERSITY OF MARYLAND, BALTIMORE', 'ORG_PRNT_UEI_NUM': None}
{'Name': None, 'CityName': None, 'StateCode': None, 'ZipCode': None, 'StreetAddress': None, 'CountryCode': None, 'CountryName': None, 'StateName': None, 'CountryFlag': None, 'CONGRESSDISTRICT': None, 'CONGRESS_DISTRICT_PERF': '""'}
{'Code': '1192', 'Text': 'NEURONAL AND GLIAL MECHANISMS'}
{'url': 'https://www.nsf.gov/awardsearch/download?DownloadFileName=1987&All=true', 'xml': '8711829.xml'}