Study of tyrosine hydroxylase immunoreactive neurons in neonate rats lactationally exposed to 2,4-dichlorophenoxyacetic Acid.
Dopaminergic neurons from the midbrain nuclei substantia nigra (SN; A9) and ventral tegmental area (VTA; A10) were investigated by tyrosine hydroxylase (TH) immunostaining in neonate rat brains exposed to 2,4-dichlorophenoxyacetic acid (2,4-D) through lactation. Dorsal raphe serotonin (5-HT) projections to SN and VTA were also studied by 5-HT transporter (5-HTT) immunostaining and results were quantified by image analysis. Twenty-five-day-old pups exposed to 2,4-D through mothers milk were used. Dams were intraperitoneally administered 70 or 100mg/kg/day of 2,4-D from the 9th to the 25th postpartum day. After 100mg/kg of 2,4-D exposure, a 25% diminution in the SN and a 33% diminution in the VTA neurons' TH immunostaining along with a significantly 5-HT fiber density diminution were observed. The present work supports previous reports which suggest that exposure to 2,4-D during development has multiple effects on CNS.
Experimental Toxicology Laboratory, School of Biochemical and Pharmaceutical Sciences, National University of Rosario, Suipacha 531, Rosario 2000, Argentina.
G
G
Garcia
P
P
Tagliaferro
A
A
Ferri
A M
AM
Evangelista de Duffard
R
R
Duffard
A
A
Brusco
D015084:2,4-Dichlorophenoxyacetic Acid / Q000633:toxicity*; D000818:Animals; D000831:Animals, Newborn; D005260:Female; D007120:Immunochemistry; D007774:Lactation / Q000378:metabolism*; D009474:Neurons / Q000737:chemistry* / Q000187:drug effects* / Q000201:enzymology; D051381:Rats; D017208:Rats, Wistar; D014446:Tyrosine 3-Monooxygenase / Q000032:analysis* / Q000378:metabolism
D015084:2,4-Dichlorophenoxyacetic Acid; D014446:Tyrosine 3-Monooxygenase