Figure 1. Localization of t-eNOS, p-eNOS at Ser¹¹⁷⁷, Ser¹¹⁶, t-Akt/PKB, p-Akt/PKB, t-ERK1/2, and p-ERK1/2 in odontoblasts. In odontoblasts and in their processes, localization of total (t)-eNOS was detected in predentin and initial dentin tubules (A). Odontoblasts revealed reaction products for phosphorylated (p)-eNOS at Ser¹¹⁷⁷ (B) and at Ser¹¹⁶ (C) in predentin. Localization of p-eNOS at Thr⁴⁹⁵ was not identifiable in odontoblasts and in their processes in predentin (D). Localization of t-Akt/PKB was detected in odontoblasts and in their processes in predentin and initial dentin tubules (E). In the odontoblast layer, p-Akt/PKB was identifiable (F). Immunohistochemical reaction product for t-ERK1/2 was localized in predentin (G). A subpopulation of odontoblasts and their processes in predentin revealed reaction product for p-ERK1/2 (H). Confocal images of 20-µm-thick sections revealed an intense staining for t-eNOS in odontoblasts and in their processes within dentinal tubules (I). The reaction product for p-eNOS at Ser¹¹⁷⁷ was detected in odontoblasts and in their processes in predentin and in initial dentin tubules (J). Localization of p-eNOS at Ser¹¹⁶ was detected in odontoblast cell bodies and in odontoblast processes in predentin and dentin (K). Localization of p-eNOS at Thr⁴⁹⁵ was not detectable in odontoblasts (L). Existence of p-eNOS at Thr⁴⁹⁵ in pulpal blood vessels (D,L; arrows) served as positive controls. Bar = (A-H) 50 µm, (I-L) 10 µm. p = dental pulp, pd = predentin, d = dentin, o = odontoblasts.