Increased postsynaptic Ca reduces mini frequency at the Drosophila larval NMJ.

Repetitive stimulation of the Drosophila larval NMJ can produce a reduction in the frequency of miniature excitatory postsynaptic currents. By buffering postsynaptic Ca , it was shown that the decrease in "mini" frequency was due to an increase in postsynaptic Ca .

Regulation of quantal currents determines synaptic strength at neuromuscular synapses in larval Drosophila.

Studies of synaptic homeostasis during muscle fiber (MF) growth in Drosophila larvae have focused on the regulation of the quantal content of transmitter release. However, early studies in crayfish and frog suggested that regulation of quantal current size may be an integral mechanism in synaptic homeostasis. To examine this further in Drosophila, we compared the electrical properties, miniature excitatory postsynaptic potentials (minEPSPs) and miniature excitatory postsynaptic currents (minEPSCs) in different-sized MFs in third-instar larvae and for a single MF during larval growth.