COMPARISON OF RAT-BRAIN MEMBRANE-ANTIGENS BY COMPLEMENT MEDIATED RELEASE OF NEUROTRANSMITTERS FROM BRAIN FRACTIONS USING ANTISERA AGAINST S-100 AND THY-1

Synaptosomal, glial and neuronal fractions were prepared from rat brain and incubated to accumulate radioactively labeled neurotransmitters. Treatment of these fractions with antisera and complement showed that anti-(Thy-1) serum gave good release (50-75% of total uptake) of all neurotransmitters tested from synaptosomal and glial fractions. GABA and glutamate were released from neuronal perikarya but not norepinephrine or serotonin. Anti-(S-100) serum gave no significant release of any neurotransmitter tested from any of the fractions, although all of them contain this protein. The membrane nature of Thy-1 and the mainly soluble nature of S-100 protein were supported. A selection for membrane antigens and neurotransmitters from different brain fractions was possible. Antigenic differences between neuronal and glial plasma membranes were suggested by results with antiserum raised against bulk-isolated rat neuronal perikarya.