Morphological transformations of cells immunopositive for GFAP, TrkA or p75 in the CA1 hippocampal area following transient global ischemia in the rat. A quantitative study

• Published in: Brain research Vol. 987; no. 2; pp. 186 - 193
• Main Authors: Soltys, Z., Janeczko, K., Orzyłowska-Śliwińska, O., Zaremba, M., Januszewski, S., Oderfeld-Nowak, B.
• Format: Journal Article
• Language: English
• Published: London Elsevier B.V 17.10.2003; Amsterdam Elsevier; New York, NY
• Subjects: Animals; Astroglia; Biological and medical sciences; CA1; Carrier Proteins - biosynthesis; Female; Fractal analysis; Glial Fibrillary Acidic Protein - biosynthesis; Hippocampus; Hippocampus - cytology; Hippocampus - metabolism; Ischemia; Ischemic Attack, Transient - metabolism; Ischemic Attack, Transient - pathology; Medical sciences; Membrane Proteins - biosynthesis; Neurology; NGF receptors; p75; Rats; Rats, Wistar; Receptor, Nerve Growth Factor - biosynthesis; Receptor, trkA; TrkA; Vascular diseases and vascular malformations of the nervous system; CA1; Astroglia; TrkA; Development and regeneration; Ischemia; Fractal analysis; Hippocampus; NGF receptors; p75; Rat; Central nervous system; Cardiovascular disease; Cell transformation; Encephalon; Vascular disease; Cerebrovascular disease; Nervous system diseases; p75 receptor; Glial fibrillary acidic protein; Rodentia; Transitory; Cerebral disorder; Vertebrata; Experimental disease; Mammalia; Animal; Central nervous system disease; trkA receptor
• ISSN: 0006-8993; 1872-6240
• DOI: 10.1016/S0006-8993(03)03327-4

Transient global ischemia induces intensive neuronal degeneration in the hippocampal CA1 pyramidal layer, accompanied by reactive transformation of glial cells. Previously, we have shown using the double immunostaining method that the NGF receptors (NGFR) p75 and TrkA are expressed mainly on subpopulations of GFAP+ astrocytes, and this expression increases progressively after ischemia. In the presented study, we analyzed quantitatively the morphological transformations of cells immunopositive for GFAP or NGF receptors in the stratum radiatum of the CA1 hippocampal area in different survival periods after ischemia, evoked by 10-min cardiac arrest in adult rats. In control brains, NGF receptors were expressed only on small cells with poorly ramified processes. After ischemia, the NGFR+ cells increased in size and morphological complexity (measured using fractal analysis). However, even 2 weeks after ischemia these cells did not reach the size and value of the fractal dimension typical of the largest GFAP+ astrocytes. Moreover, the reaction of NGFR+ cells was significantly delayed in comparison with the total astrocyte population. The obtained results suggest that NGF receptors are expressed mainly by immature astrocytes and ischemia induces the maturation of these cells.