Expression of GAD, TH, POMC, PKCδ, and AC VII mRNA in arcuate neurons. Two representative gels illustrating that single arcuate neurons express mRNA for TH, GAD, PKCδ, AC VII, and GAPDH (A) or mRNA for POMC, GAD, PKCδ, AC VII, and GAPDH (B). The expected size of the PCR products is as follows (in bp): GAD, 207; TH, 223; POMC, 344; PKCδ, 251; AC VII, 235; and GAPDH, 212. GAPDH transcripts were analyzed in the same cells as an internal control for the RT reaction. One cell contained no RT as a negative control (-RT). Basal hypothalamic tissue RNA was also reverse transcribed in the presence of RT (tissue controls, +). A tissue control without RT (-) was included in each experiment. In addition, the following controls were included: HBSS from the dispersed cellular milieu and a water blank, both of which were negative after RT-PCR (data not shown).