Fig. 4

Glutamate evoked whole-cell currents recorded from voltage-clamped fetal mouse cortical neurons in culture are modulated by paraneoplastic syndrome patient sera

Calibration bars are 10 sec and 1 pA throughout. (A) Glutamate (100 µM) evoked currents are enhanced by Patient 1 sera (PT1, 1:4) and by affinity-purified antibody to GluR5 (1:2) in the same neuron. (B) Glutamate receptor current enhancement was seen in a subset of neurons with other patient sera (e.g.. Patient 3 [PT3], 1:4). (C) Serum from Patient 4 (PT4, 1:4) and 6 (PT6, 1:4) or (D) a control, nondiseased control patient (CNTL) did not enhance glutamate-evoked currents. Healthy human control sera and rabbit sera consisting of antibodies raised to GluR5 fusion protein or neuronal nicotinic acetylcholine receptor subunit β2 (nAChR2).