Developmental changes in the content of dopamine in the olfactory bulb of the European eel (Anguilla anguilla).
The concentrations of dopamine (DA) and of its major metabolite, dihydroxyphenylacetic acid (DOPAC), were measured in discrete areas of the eel brain. To investigate the developmental changes in the content of DA and DOPAC, the assays were performed in yellow eels (i.e. at the feeding stage) and silver eels (i.e. at the migratory stage). DA and DOPAC were unevenly distributed in the eel brain. In yellow eels, the concentration of DA was highest (16-19 pmol/mg protein) in the olfactory bulb (OB), mesencephalic tectum-diencephalon (MT-D) and medulla oblongata (MO) and lowest in the cerebellum (CB, 1 pmol/mg protein), whereas intermediate values were measured in the telencephalon (TE; 10 pmol/mg protein). The metabolic rate of DA, as reflected by the DOPAC/DA ratio, was highest in the OB and CB, with progressively smaller values being observed in the TE, MT-D, and MO. A significant increase in the concentrations of DA (+80%) and DOPAC (+122%) was observed in the OB of silver eels compared with yellow eels, whereas no significant differences were detected in the concentrations of DA and DOPAC in the other brain areas as a function of the developmental stage. The results are discussed in terms of the possible involvement of environmental, behavioral and developmental factors.
Giorgi
O
O
Department of Toxicology, University of Cagliari, Italy.
Deiana
A M
AM
Salvadori
S
S
Lecca
D
D
Corda
M G
MG
D015102:3,4-Dihydroxyphenylacetic Acid / Q000378:metabolism; D000811:Anguilla / Q000378:metabolism*; D000818:Animals; D001923:Brain Chemistry / Q000502:physiology; D004298:Dopamine / Q000378:metabolism*; D009830:Olfactory Bulb / Q000254:growth & development* / Q000378:metabolism*
D015102:3,4-Dihydroxyphenylacetic Acid; D004298:Dopamine