Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0155339 (Brown)
 12,436 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The effect of aging on the hippocampal formation of the male Brown Norway rat was studied by immunohistochemistry and measurements of the immunoreactive hippocampal cells using stereological techniques. The total estimated number of glucocorticoid receptor (GR) immunoreactive neurons of the CA1-CA2 area did not differ in the 3- and the 36-month-old rat. However, the intensity of the GR immunoreactivity was decreased in the aged animals. A gradual decrease of the immunoreactivity for the mineralocorticoid receptor was also observed in the CA1-CA2 area. In the stratum oriens and the stratum radiatum of the CA1-CA2 area the immunoreactivity for basic fibroblast growth factor (bFGF) present in the glia was found to be reduced [20,000 +/- 2100 (n = 6)] in the 36-month-old rat vs the 3-month-old rat [28,500 +/- 4500 (n = 4) (*P = 0.05)]. However, there was no difference in the number of glial fibrillary acidic protein immunoreactive cells of this area in these two age groups. The present findings give evidence that in the Brown Norway rat there is no loss of the neuronal population containing glucocorticoid receptors of the CA1-CA2 area during aging but suggest that aging is characterized by deficits of glially derived growth factors, such as bFGF.
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PMID:Basic fibroblast growth factor and steroid receptors in the aging hippocampus of the brown Norway rat: immunocytochemical analysis in combination with stereology. 795 Sep 68

Microdensitometrical and stereological techniques were applied to study the effects of aging on the hippocampus of 3-, 6-, 12-, 18-, 24-, 30-, and 36-month-old male Brown Norway rats. Stereological analysis of basic fibroblast growth factor (bFGF) immunoreactive glial cells in the CA1 area showed an age-dependent decrease in the number of cells, starting at 18 months of age. Specific mean gray values of the immunoreactivity for bFGF were reduced in the CA3 area, in the dentate gyrus, and in fields of the CA1 area, starting at 24 months of age. There were no differences between the age groups in the number of glial fibrillary acidic protein or glucocorticoid receptor (GR) immunoreactive cells of the CA1-CA2 areas. However, the intensity of the GR immunoreactivity was decreased in the 18-month-old and older rats. No changes in the immunoreactivity for the mineralocorticoid receptor were observed in the CA1-CA2 areas of any of the age groups. Spontaneous alternation test and reactivity in an open field did not reveal marked differences between the age groups. These findings give evidence that there is a loss of neural GR immunoreactivity, but no loss of GR immunoreactive neurons, in the CA1-CA2 areas of the aged Brown Norway rat. Aging may also be characterized by substantial deficits of glially derived growth factors, such as bFGF in the hippocampus. The changes in immunoreactivities were not correlated to alterations in selected behaviors dependent on normal hippocampal function.
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PMID:Neurochemical changes in the hippocampus of the brown Norway rat during aging. 926 98

Using quantitative receptor autoradiography, we assessed binding site densities and distribution patterns of glutamate, GABA(A), acetylcholine (ACh), and monoamine receptors in the hippocampus of 32-month-old Fischer 344/Brown Norway rats. Prior to autoradiography, the rats were divided into two groups according to their retention performance in a water maze reference memory task, which was assessed 1 week after 8 days of daily maze training. The animals of the inferior group showed less long-term retention of the hidden-platform task but did not differ from superior rats in their navigation performance during place training and cued trials. The decreased retention performance in the group of inferior learners was primarily accompanied by increased alpha(1)-adrenoceptors in all hippocampal subregions under inspection (CA1-CA4 and dentate gyrus), while elevated alpha(2)-adrenoceptor binding was observed in the CA1 region and DG. Furthermore, inferior learners had higher NMDA binding in the CA2 and CA4 and increased 5-HT(1A) binding sites in the CA2, CA3, and CA4 region. No significant differences between inferior and superior learners were evident with regard to AMPA, kainate, GABA(A), muscarinergic M(1), dopamine D(1), and 5-HT(2) binding densities in any hippocampal region analyzed. These results show that increased NMDA, 5-HT(1A), and alpha-adrenoceptor binding in the hippocampus is associated with a decline in spatial memory. The increased receptor binding observed in the group of old rats with inferior maze performance might be the result of neural adaptation triggered by age-related changes in synaptic connectivity and/or synaptic activity.
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PMID:Impaired maze performance in aged rats is accompanied by increased density of NMDA, 5-HT1A, and alpha-adrenoceptor binding in hippocampus. 1711 11