Expressions of zebrafish monocarboxylate transporters ( drmct s) in brains and various tissues. (A) RT-PCR analysis (35-cycle amplification) of zebrafish monocarboxylate transporters (drmct s) homologues in brain, gill, eye, spleen and liver tissues of zebrafish. Zebrafish ribosomal protein L13A (drrpl13a) was chosen as the positive control. (B-D) Double-labeling of ZN12 (a marker of neurons, fluorescent red signals) or GFAP (a marker of astrocytes, fluorescent red signals) with novel drmct1b (B-1, B’-1), drmct2b (C-1, C’-1) and drmct4b (D-1, D’-1) (fluorescent green signals) RNA probes in adult zebrafish transverse brain sections. The hypothalamus section positively labeled by the drmct1b as well as drmct2b antisense probes showed colocalized signals with anti-ZN12 antibody (B-3, C-3) but did not colocalized with anti-GFAP antibody (B’-3, C’-3). RNA signals of drmct4b were partially colocalized with anti-ZN12 (D-3) and anti-GFAP (D’-3) antibodies. White arrow head: colocalization signals (fluorescent yellow) of drmct mRNA and ZN12/GFAP; blue bold arrow: labeled-cells (fluorescent green) expressed only drmct mRNA; light-gray arrow: labeled-cells (fluorescent red) expressed only GFAP; Scale bar: 10 μm.