Figure 7. Ultrastructural features of lanceolate complexes revealed by EM using tannic acid-treated specimens.
(A–C) Cross sections of lanceolate complexes at guard, awl/auchene, and zigzag hair follicles. Small vesicles can be observed within axon terminals (arrows in A–C). TSC processes contain fine filaments that are nearly parallel to the long axis of the follicle and therefore appear as dark spots within the cytoplasm. Numerous pinocytotic vesicles are associated with both the inner and outer surfaces of TSC processes (arrowheads in A–C). (D–G) Hemidesmosomes are seen along plasma membranes of hair follicle outer root sheath cells that face LTMR axons and TSC processes (white arrowheads). Fine filament-like structures emanate from the hemidesmosomes, traverse the basal lamina, and form contacts with LTMR axon terminals and TSC processes. Axon terminals are labeled with ‘N’; TSC processes are labeled with ‘S’. Animals around 4 weeks of age were used in these experiments. Scale bars, 100 nm.