Fig. 8

GABA and GAD in sensory neurons of walking legs. a Fluorescence image of GABA-IR in the tibia of a walking leg. The position of the cuticle is indicated by a dashed line. Arrowheads point to individual sensory neurons extending a dendrite through the cuticle. Arrows point to sensory nerve branches collecting the axons of sensory neurons. b Confocal image (maximum projection of 17 images at 3 μm intervals) of GAD-IRin sensory neurons (arrowheads) in the tibia. c Combination of the same confocal image as in b with a transillumination photomicrograph of the cuticle, displaying three large (arrows) and one smaller (arrowhead) sensilla innervated by dendrites of GAD-IR sensory neurons and corresponding sensory nerve branches (red). d Confocal image (maximum projection of 19 images at 1.8 μm intervals) of GAD-IR (green) in the distal part of the femur. One or two sensory neurons (arrowheads) extend dendrites into each of the sensilla (arrows) that can be seen as mdark outlines against the deliberately strong green background fluorescence. e Combination of a confocal image (maximum projection of 13 images at 2 μm intervals) of a GAD-IR sensory neuron (arrowhead) extending a dendrite into the socket of a sensillum (arrow). f Confocal image (maximum projection of 23 images at 1 μm intervals) of GABA-IR in the leg nerve (n4) in the region of the trochanter. Arrowheads point to large GABA-IRaxons (presumptive motor neuron axons), arrows point to small GABA-IR axons (presumptive afferents). Distal is to the right in all panels. Scale bars: a 200 μm, b-d 100 μm, e 20 μm, f 50 μm