SUMMARY1. Adult goldfish retinas were enzymatically dissociated and ganglion cells were maintained in culture for periods of 1-5 days. Ganglion cells could be identified by their morphology, and this identification was confirmed by retrograde transport of the fluorescent dye Fast Blue injected into the optic nerve stub.2. All the ganglion cells tested responded to 30 ,tM-GABA or 100 /IM-glycine between 2 and 30 h after enzymatic dissociation of the retina.3. Whole-cell responses to 30 jM-GABA or glycine declined over a period of seconds during sustained applications of the agonists, probably as a result of desensitization. There was an irreversible decline in the peak whole-cell response to repeated applications of 30 /tM-GABA unless the pipette-filling solution contained 2 mM-ATP, 4 mM-Mg2", 10 mM-EGTA and no added Ca2+. Both GABA and glycine responses also showed an irreversible decline in outside-out patches but, in this case, Mg2+, ATP, and very low Ca2+ failed to stabilize the response.4. Whole-cell currents activated by both GABA and glycine were demonstrated to be chloride-selective by investigating the dependence of reversal potential (VT) on internal chloride concentration ([CFi) For GABA responses, the dependence of Vr on [Cl-]i could not be distinguished from that predicted by the Nernst relation. For glycine, deviations from Nernstian dependence were observed, but the permeability to Cl-was at least 20 times greater than to isethionate, S042-, or monovalent cations

Neutrophils that bear receptors for the Fc portion of immunoglobulin G have been demonstrated to be more active in assays of adherence, aggregation, and chemotaxis compared to Fc receptor-negative cells. We examined the relationship of neutrophil Fc receptor activity and cell-cell adherence or aggregation induced by phorbol myristate acetate. In contrast to 1-isoproterenol, isobutyl-methyl-xanthine, and dibutyryl cAMP, each of which inhibited Fc receptor activity and neutrophil aggregation, theophylline significantly impaired aggregation without affecting Fc receptor activity. The selective beta-2 agonist, metaproterenol, and 8-Bromo cAMP failed to inhibit Fc receptor activity or neutrophil aggregation. Three known inducers of neutrophil intracellular cyclic AMP, PGE1, PGE2, and cholera toxin, also did not inhibit Fc receptor activity. Inhibition of Fc receptor activity by 95% in the presence of purified Fc fragments did not affect neutrophil aggregation. Similarly suppression of Fc receptor activity by purified Fc fragments did not inhibit neutrophil adhesion to nylon fiber columns. These data demonstrate that the Fc receptor does not mediate phorbol myristate acetate-induced cell-cell adhesion and is not necessary for optimal neutrophil adhesion to nylon fibers. Our results are consistent with the possibility that the reversible inhibitory activity of beta-adrenergic agonists on rosette formation may be a steric effect rather than a metabolic effect. These data tend to dissociate Fc receptor activity, neutrophil aggregation, and adhesion and support the hypothesis that the Fc receptor may be a marker of neutrophil heterogeneity rather than a component necessary for optimal neutrophil aggregation or adhesion.