Effect of Calcium and Inositol Polyphosphates on Nerve Cell Function
{'Code': '08090200', 'Directorate': {'Abbreviation': 'BIO', 'LongName': 'Direct For Biological Sciences'}, 'Division': {'Abbreviation': 'IOS', 'LongName': 'Division Of Integrative Organismal Systems'}}
{'SignBlockName': None}
Variations in the intracellular concentration of calcium ions                   (Ca) play an important role in a wide range of cellular reactions               and processes.  In most cells, brief increases in Ca can result                 either from calcium entering the cell or calcium being released                 from a specialized compartment inside the cell.  Calcium can be                 released from an intracellular compartment when an agonist                      (hormone or neurotransmitter) binds to a distinct receptor on the               cell membrane.  According to this model, binding of the agonist                 (first messenger) to the membrane receptor leads  to the                        intracellular release of an agent (second messenger).  The second               messenger, in turn, releases calcium from the intracellular                     compartment.                                                                                                                                                    The proposed study will focus on characterizing the action of a                 novel second messenger, called inositol trisphophate (IP3), on                  nerve cells.  The experiments will be carried out in giant                      molluscan neurons.  Molluscan neurons constitute a particularly                 favorable prepartion in which to study calcium function and                     regulation.  Some nerve cells display a prominent calcium                       component in the ionic basis of their excitability.  Their cell                 bodies are quite large (0.1-0.5mm in diameter, about 10 times                   larger that mammalian neurons), and are easily identifiable for                 isolation.  For these reasons, experimental manipulations can be                made in these cells which would be impossible in the mammalian                  nervous system.                                                                                                                                                 Preliminary studies suggest that intracellular injections of                    inositol trisphosphate cause an increase in intracellular calcium               stores.  The proposed experiments will:                                                                                                                         1. Look for an agonist that causes Ca to increase by puffing                    pharmacological agents on the cell membrane and measuring the                   level of Ca with calcium-selective probes made in the laboratory.                                                                                               2. Compare the Ca increases induced by the agonist or IP3 by                    either puffing the agonist or injecting IP3 and measuring Ca.                                                                                                   3. Determine the localization of the intracellular Ca store by                  injecting IP3 at different depths fro the inner membrane of a                   nerve cell and measuring the free Ca change at each depth.                                                                                                      4. Determine the effects of IP3 injections on the electrical                    characteristics of the cells and correlate them with the                        intracellular free calcium level.                                                                                                                               The studies will suggest whether the action of some                             neurotransmitters on nerve cells is mediated by an increase in                  calcium released by inositol trisphosphate.  The combination of                 these electrophysiological, pharmacological and biochemical                     techniques should prove useful to gather new and important                      information about nerve cell function and perhaps about disorders               of the human central nervous system.
{'FirstName': 'Simon', 'LastName': 'Levy', 'EmailAddress': 'simonL@bu.edu', 'StartDate': '04/01/1989', 'EndDate': None, 'RoleCode': 'Principal Investigator'}
{'Name': 'Trustees of Boston University', 'CityName': 'BOSTON', 'ZipCode': '022151300', 'PhoneNumber': '6173534365', 'StreetAddress': '881 COMMONWEALTH AVE', 'CountryName': 'United States', 'StateName': 'Massachusetts', 'StateCode': 'MA'}
{'Code': '1192', 'Text': 'NEURONAL AND GLIAL MECHANISMS'}
{'url': 'https://www.nsf.gov/awardsearch/download?DownloadFileName=1988&All=true', 'xml': '8820001.xml'}