Fig. 3

Expression of 5-HT_2C receptor as detected in whole-mount in-situ hybridization preparations. A — top view of head, ventral focus, B — top view of head, dorsal focus, C — side view of head, D — side view of tail region, E — negative control staining (with sense RNA probe), F — organization of stained neuron clusters in top view, and G — organization of stained neuron clusters in side view. Accumulations of labeled cell bodies are visible in close proximity to and along the midline of the brain. In A, two labeled clusters (2 and 3, arrows) are labeled strongly. In B, the clusters in a more dorsal focal plane are not as intensively labeled as in A, but stained cells can be grouped into clusters 4–9 (see F and G). In D, the arrows indicate dorsal cell bodies in the spinal cord. (E) A sense probe against the 5′ end of the 5-HT_2C receptor mRNA was used for the detection and did not yield any staining. The organization of stained neuron clusters 1–9 is depicted in F (top view) and G (side view). Ventral clusters are indicated in dark gray and dorsal clusters are indicated in light gray. Cluster designation: 1 — preoptic, 2 — ventral thalamus, 3 — posterior tuberculum, 4 — dorsal thalamus, 5- pretectum, 6 — dorsal tegmentum, 7 — ventral tegmentum, 8 — anterior medulla, 9 — posterior medulla. Scale bar in A–C, E — 120 μm; scale bar in D — 60 μm.