Developmental delay of astrocytes in hippocampus of rhesus monkeys reflects the effect of pre- and postnatal chronic low level lead exposure.
Rhesus monkeys were pre- and postnatally exposed to lead-acetate at 0, 350, or 600 ppm in diet for nine years, followed by a period of lead-free diet for 32 months. During this time blood lead levels declined to normal, but still showed dose-related differences. In behavioral and neurophysiological studies the rhesus monkeys exhibited dose-related cognitive and functional deficits. After sacrifice hippocampal sections were processed for immunohistological staining. GFAP, introduced as a marker of neurotoxicity and Vimentin, which is expressed by immature or reactive astrocytes were investigated. A dose-dependent increase of GFAP due to prenatal and chronic low level lead exposure was not observed. We found a dose-related increase of GFAP-positive radial glia and star-shaped Vimentin-positive astrocytes in the high lead group. We consider these findings as indication of immature astrocytes, which are not able to react with gliosis in respond to pre- and postnatal low level lead exposure. The lack of pronounced glial response due to low level lead exposure may result in a delay of astrocytic differentiation, shown by persistence of radial glia.
Institute of Neuropathology, Freie Universitaet Berlin, Germany.
K
K
Buchheim
S
S
Noack
G
G
Stoltenburg
H
H
Lilienthal
G
G
Winneke
D000818:Animals; D001253:Astrocytes / Q000187:drug effects*; D004305:Dose-Response Relationship, Drug; D005260:Female; D005333:Fetus / Q000187:drug effects*; D005904:Glial Fibrillary Acidic Protein / Q000032:analysis; D006624:Hippocampus / Q000737:chemistry / Q000187:drug effects*; D007854:Lead / Q000633:toxicity*; D008253:Macaca mulatta; D008297:Male; D011247:Pregnancy; D014746:Vimentin / Q000032:analysis
D005904:Glial Fibrillary Acidic Protein; D014746:Vimentin; D007854:Lead