An inhibitory effect of interferon gamma on the injury-induced astrocyte proliferation in the postmitotic rat brain.
Influence of interferon gamma (IFNgamma) on astrocytes proliferating in response to unilateral injury of the cerebral hemisphere was investigated in 30-day-old rats. The brain injury was followed by an immediate injection of IFNgamma into the lesion cavity. On 1st or 2nd day following injury the animals were injected with [3H]thymidine and killed 4 h after the injection. The proliferating astrocytes were visualised by combination of immunocytochemical staining for glial fibrillary acidic protein (GFAP) and autoradiography. Thereafter, numbers of GFAP-immunopositive and autoradiographically-labeled astrocytes located within the region of injury were counted. On the day 1 after injury no effect of IFNgamma administration was seen. However, on day 2 the average 43% reduction of the number of proliferating astrocytes was recorded. The reduction showed no dose-dependent changes. This in vivo evidence of IFNgamma-induced suppression of astrocyte proliferation was considered in relation to other determinants of astrocyte reactivity existing in the injured brain.
Pawliński
R
R
Department of Neuroanatomy, Institute of Zoology, Jagiellonian University, Kraków, Poland.
Janeczko
K
K
D000818:Animals; D001253:Astrocytes / Q000187:drug effects / Q000473:pathology*; D001921:Brain / Q000187:drug effects / Q000473:pathology*; D001930:Brain Injuries / Q000473:pathology*; D002455:Cell Division / Q000187:drug effects; D004247:DNA / Q000096:biosynthesis; D005904:Glial Fibrillary Acidic Protein / Q000032:analysis; D007371:Interferon-gamma / Q000008:administration & dosage / Q000494:pharmacology*; D008297:Male; D008845:Microinjections; D008938:Mitosis; D051381:Rats; D017208:Rats, Wistar; D011994:Recombinant Proteins; D013936:Thymidine / Q000378:metabolism
D005904:Glial Fibrillary Acidic Protein; D011994:Recombinant Proteins; D007371:Interferon-gamma; D004247:DNA; D013936:Thymidine