Spatio-temporal activities in the antennal lobe analyzed by an optical recording method in the male silkworm moth Bombyx mori

Optical recordings with a voltage-sensitive dye showed that the spatio-temporal pattern of depolarizing responses evoked by electrical stimulation of antennal nerve (AN) was non-homologously distributed in the antennal lobe (AL) of the male silkworm moth: Bombyx mori. Time courses of postsynaptic activities and GABAergic inhibitory potentials of AL neurons were individually demonstrated by pharmacological experiments, i.e. Ca2+ free and bicuculline conditions. GABAergic inhibitory potentials began with a ca. 3 ms delay from the beginning of the postsynaptic activities. Intensity of the postsynaptic activities and GABAergic inhibitory potentials were non-homologously distributed in the AL. Relatively strong postsynaptic activities and GABAergic inhibitory potentials were consistently observed in some parts of the macroglomerular complex (MGC) and/or in some ordinary glomeruli (Gs) in the medial and ventral part of the AL. (C) 1998 Elsevier Science Ireland Ltd. Ali rights reserved.