Anatomical and neurochemical organization of the lower division of the locust central body (CBL). (A) Frontal Bodian-stained paraffin section through the central complex and lateral complexes. CBL, lower division of the central body; CBU, upper division of the central body; LAL, lateral accessory lobe, LBU, lateral bulb; PB, protocerebral bridge. (B) Frontal Vibratome section illustrating dense γ-aminobutyric acid (GABA) immunolabeling in the CBL, revealed by the peroxidase-antiperoxidase (PAP) technique as described by Homberg et al. (1999). (C) Immunostaining of the CBL on frontal Vibratome section using an antiserum against locustatachykinin II (LomTK II); PAP technique as described by Vitzthum and Homberg (1998). (D,E) Two types of columnar (D) and tangential (E) neuron innervating the CBL. Frontal camera lucida reconstructions of Neurobiotin- or Lucifer Yellow-labeled neurons were projected onto the standard locust central complex (el Jundi et al., 2010). (D) Columnar neuron 1 and 2 (CL1, CL2). NO, nodulus. (E) Tangential neuron 2 and 3 (TL2, TL3). MBU, medial bulb. Scale bars: 100 μm.