. The Biological bulletin. Biology; Zoology; Biology; Marine Biology. NEUROBIOLOGY 299 Reference: Biol. Hull 185: 299-300. (October. 1993) Activity-Dependent Inhibition of Neurotransmitter Release by Brefeldin A 5. T. Brady (Depl. of Cell Biology ami \euroscience. University of Texas Southwestern Medical Center, 5323 Harry Hines Blvd., Dallas, TX 75235-9111), M. Suginwri, P. L. Leopold, Lin, D. S. Chit, andR. Llinds The fungal metabolite Brefeldin A (BFA) disrupts membrane sorting in the Golgi complex and the endocytic and secretory compartments of nonneuronal cells (1,2) by inducing the
. The Biological bulletin. Biology; Zoology; Biology; Marine Biology. NEUROBIOLOGY 299 Reference: Biol. Hull 185: 299-300. (October. 1993) Activity-Dependent Inhibition of Neurotransmitter Release by Brefeldin A 5. T. Brady (Depl. of Cell Biology ami \euroscience. University of Texas Southwestern Medical Center, 5323 Harry Hines Blvd., Dallas, TX 75235-9111), M. Suginwri, P. L. Leopold, Lin, D. S. Chit, andR. Llinds The fungal metabolite Brefeldin A (BFA) disrupts membrane sorting in the Golgi complex and the endocytic and secretory compartments of nonneuronal cells (1,2) by inducing the ac- cumulation of intermediate membranous organelles that are normally transient. The molecular mechanisms of BFA are in- completely understood, but appear to act at a step requiring a small G-protein (). Because synaptic vesicles must be recycled in the presynaptic terminal (5-7), we examined actions of BFA on the electrophysiology of pre- and postsynaptic cells of the squid giant synapse at concentrations that disrupt the Golgi complex in most cells. The actions of BFA on neurotransmitter release and synaptic vesicle recycling at the squid giant synapse were assessed by a combination of electrophysiology (8,9) and quantitative electron microscopic morphometry. Injection of BFA into the presynaptic terminals stimulated at 3 Hz produced a rapid decrease in the postsynaptic response without altering the electrical properties of the presynaptic terminal (Fig. 1). Stimulation at Hz pro- duced minimal changes in the postsynaptic potential over a pe- riod of 30-35 min, whereas stimulation at 3-5 Hz led to a loss of the postsynaptic response in 7-10 min. Electron microscopic analysis of terminals injected with BFA or treated with BFA as the bathing solution showed a substantial accumulation of irregular membranous organelles in the pre- synaptic terminal. These organelles were significantly larger than normal synaptic vesicles; indeed, when BFA was applied in the bath, they
Size: 1774px × 1408px
Photo credit: © Library Book Collection / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bookauthorlilliefrankrat, booksubjectbiology, booksubjectzoology
