B. Caronti et al., Treatment with 6-hydroxydopamine in planaria (Dugesia gonocephala s.l.): morphological and behavioral study, COMP BIOC C, 123(3), 1999, pp. 201-207
Citations number
24
Categorie Soggetti
Pharmacology & Toxicology
Journal title
COMPARATIVE BIOCHEMISTRY AND PHYSIOLOGY C-PHARMACOLOGY TOXICOLOGY & ENDOCRINOLOGY
Morpho-functional and behavioral effects of exposure to 6-hydroxydopamine (
OHDA)-HCl (24 mu g/ml per day for 24 h and 7 days) were studied in planaria
s (Dugesia gonocephala s.l.). Exposure to 6-OHDA-HCl for 24 h produced hypo
kinesia of the specimens. These behavioral changes were more pronounced, le
ading to complete immobility, after 7 days of exposure to the neurotoxin. M
oreover, specimens exposed to 6-OHDA-HCl for 24 h and 7 days failed to show
any behavioral response to nomifensine, thus furnishing evidence of the da
mage of presynaptic dopamine terminals. Exposure to 6-HDA-HCl for 24 h sign
ificantly reduced cathecolamine content in neuropil region, as demonstrated
by histochemistry, and electron-dense presynaptic vesicles, as observed on
electron microscopy examination. All these alterations were significantly
more pronounced and were accompanied by swelling and strong increase of ele
ctron-density in cytoplasm of numerous neurons after exposure to the neurot
oxin for 7 days. This appears to be the first demonstration of the neurotox
ic effects of 6-OHDA-HCl in flatworms. (C) 1999 Elsevier Science Inc. All r
ights reserved.