FIGURE 2.

H₁R expression in the ventral mesencephalon of 12- and 14-day-old embryos. (A) Representative agarose gels of the PCR products for H₁R and GAPDH (internal control) from control E12 and E14 vMes tissue. –Ctl, negative control (500 ng total RNA without retrotranscription); +Ctl, positive control (500 ng cDNA from adult cerebral cortex). (B) Semi-quantitative densitometry analysis for H₁R expression at E12 and E14. Values are expressed as percentage of the optic densities obtained at E12 and are means ± standard error (SEM) from eight experiments. (C) Specific [³H]-mepyramine binding to membranes. Values are expressed as fmol/mg protein, and are means ± SEM from five experiments. Membranes from adult cerebral cortex and human astrocytoma U373 MG cells were used as positive controls. P-values were obtained after two-tailed unpaired Student’s t-test. (D) H₁R immunodetection. Left, coronal view of the mesencephalon at E12. The area outlined in red corresponds to the area shown in the representative epifluorescence micrographs (20×) on the right, which show independent and merged channels for H₁Rs (red), Nestin (green), and DAPI (blue). MZ, marginal zone; VZ, ventricular zone; TNE, tegmental neuroepithelium; varp, aqueduct pretectal; vat, aqueduct tegmental; vl, ventricular lumen. Scale bar, 100 μm.