Figure 1.

Biotin-labeled ZIP penetrates the connective tissue and enters inside neurons. Biotin-labeled peptide was conjugated to HRP-avidin, and then visualized by DAB reaction (see Materials and Methods). A, Low-power micrograph of a cryostat section of the pleural ganglion from an animal given a vehicle injection. Note the absence of DAB staining after biotin detection processing. B₁, Low-power micrograph of a cryostat section of the pleural ganglion from an animal given an injection of biotin-labeled myristoylated ZIP. B₂, Higher power micrograph of the area indicated by the red box in B₁. There is strong immunocytochemical staining in the connective tissue sheath surrounding the ganglion, as well as inside neurons. Scale bars: A, B₁, 100 μm; B₂, 50 μm.