CS axon terminals reconstructed across several serial adjacent C8 sections. A, 8 weeks. B, Mature. Two examples of axons from a BTX-injected animal are shown in A1 and an age-matched control in B1. Examples of CS terminals in two BTX-injected animals are shown in A2 (top, PW30; bottom, PW77), and three controls in B2 (all PW30). Scale bars, 100 μm.