Figure 2. In situ hybridization of CNR1 and CNR5 mRNA in the rat incisor. (A) Whole stages of ameloblasts and odontoblasts. Arrows indicate the points of the signal that disappeared in ameloblasts. (B) Tissues were hybridized with CNR5 antisense (a,d,g,j), CNR1 antisense (b,e,h,k), and CNR5 sense cRNA probes (c,f,i,l). Bulbous portion of the odontogenic epithelium (a,b,c); secretory stage (d,e,f); early-maturation stage (g,h,i); and late-maturation stage (j,k,l). Magnification: x40. am, ameloblasts; od, odontoblasts. (C) High magnification of CNR5 mRNA expression. CNR5 antisense (a, c, e) and sense cRNA probes (b, d, f); secretory stage (a, b); early-maturation stage (c, d); and late-maturation stage (e, f). Magnification: x200. am, ameloblasts; pc, papillary cell layer. Scale bars: 50 µm (Bl); 20 µm (Cf).