1. Learning impairment caused by intra-CA1 microinjection of testosterone increases the number of astrocytes.
- Author
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Emamian S, Naghdi N, Sepehri H, Jahanshahi M, Sadeghi Y, and Choopani S
- Subjects
- Analysis of Variance, Animals, Behavior, Animal, Cell Count methods, Hippocampus pathology, Male, Maze Learning drug effects, Microinjections methods, Neurons pathology, Rats, Rats, Wistar, Reaction Time drug effects, Androgens pharmacology, Astrocytes pathology, Hippocampus drug effects, Learning Disabilities chemically induced, Learning Disabilities pathology, Testosterone pharmacology
- Abstract
The hippocampus is essentially involved in learning and memory, and is known to be a target for androgen actions. As neuron-astrocyte interactions play a crucial role during development and in the adult brain, it is thought that astrocytes support learning and memory through specific mechanisms. In this study, the effect of testosterone-induced impairment of acquisition and retrieval of long-term memory, on the number of astrocytes was studied. Adult male albino Wistar rats were bilaterally cannulated into the CA1 region and received 80 microg/0.5 microl of testosterone enanthate dissolved in DMSO as vehicle. In trained groups injection was done 30 min before training. Our results showed that pre-training administration of testosterone increased escape latency and the traveled distance, as compared to intact or DMSO administered (sham-operated) counterparts. Testosterone administration also increased the number of astrocytes in rats, compared to sham-operated and intact animals in both trained and non-trained groups. We have also found that spatial learning could increase the number of astrocytes in the hippocampus as a center of long-term learning and memory and recall. It is concluded that, testosterone-induced impairment in learning and memory, causes an increase in the number of astrocytes in the CA1 region of rat hippocampus., (Copyright 2009 Elsevier B.V. All rights reserved.)
- Published
- 2010
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