Effects of glucocorticoids in the gp120-induced inhibition of glutamate uptake in hippocampal cultures.
Studies examining the development of AIDS Related Dementia have concentrated on neurotoxic properties of the HIV viral coat protein, gp120. We have previously shown that this neurotoxicity can be exacerbated by glucocorticoids (GCs), the stress hormones secreted by the adrenal. Moreover, GCs also worsen several of the mechanisms mediating gp120 neurotoxicity, such as increased calcium flux, ROS generation, and energy depletion. Gp120 interferes with the reuptake of glutamate in glia cultures, another possible mechanism by which it can be neurotoxic. This paper examines the role of GCs in exacerbating this phenomenon. It was found that while GCs do not exacerbate the decrease in reuptake of glutamate in glia cultures, they do enhance the decrease in mixed neuronal cultures and this latter effect appears to be energy-dependent.
Brooke
Sheila M
SM
Department of Biological Sciences, Gilbert Building Rm 432, Stanford University, Stanford, CA 94305-5020, USA. sheila.brooke@stanford.edu
Sapolsky
Robert M
RM
D000818:Animals; D001692:Biological Transport / Q000187:drug effects; D002478:Cells, Cultured; D004305:Dose-Response Relationship, Drug; D004347:Drug Interactions; D005938:Glucocorticoids / Q000494:pharmacology*; D005947:Glucose / Q000494:pharmacology; D018698:Glutamic Acid / Q000378:metabolism*; D015699:HIV Envelope Protein gp120 / Q000494:pharmacology*; D006624:Hippocampus / Q000187:drug effects* / Q000378:metabolism; D009457:Neuroglia / Q000187:drug effects / Q000378:metabolism; D051381:Rats; D013997:Time Factors
D005938:Glucocorticoids; D015699:HIV Envelope Protein gp120; D018698:Glutamic Acid; D005947:Glucose