Antigen-induced activation of hypothalamic cells (assessed by expression of the c-fos gene).
The aim of the present work was to study the activation of the expression of the c-fos gene (by in situ hybridization) in cells from rat (Sprague Dawley) hypothalamic structures 0.5, 2, 6, and 16 h after i.v. injections of tetanus toxoid (200 microg/kg). Tetanus toxoid was selected as the antigen because it does not induce any general non-specific body reactions. Control animals received i.v. doses of apyrogenic physiological saline. The number of c-fos mRNA-positive cells in all the hypothalamic structures studied was insignificant 30 min after injections of tetanus toxoid. c-fos mRNA-positive cells were seen in the posterior, lateral, and anterior hypothalamic fields and in the dorsomedial and ventromedial hypothalamic nuclei 2 h after injections of tetanus toxoid. The intensity of c-fos mRNA expression decreased in the posterior, lateral, and anterior hypothalamic fields 6 h after injections of tetanus toxoid. The maximum number of c-fos mRNA-positive cells in the anterior field and the paraventricular nucleus of the hypothalamic induced by tetanus toxoid, as compared with reactions to administration of physiological saline, were seen at 6 h. Administration of tetanus toxoid and physiological saline did not active the synthesis of c-fos mRNA in the arcuate or supraoptic nuclei at any time point. The number of c-fos mRNA-positive cells returned to baseline by 16 h after tetanus toxoid injections. Thus, this study revealed the temporospatial pattern of activation of hypothalamic structures in response to exposure to an antigen.
Nosov
M A
MA
Science Research Institute of Experimental Medicine, Russian Academy of Medical Sciences, St. Petersburg.
Barabanova
S V
SV
Glushikhina
M S
MS
Kazakova
T B
TB
Korneva
E A
EA
D000818:Animals; D000941:Antigens / Q000276:immunology; D007031:Hypothalamus / Q000166:cytology / Q000276:immunology / Q000378:metabolism*; D017403:In Situ Hybridization; D008297:Male; D015213:Neuroimmunomodulation; D016760:Proto-Oncogene Proteins c-fos / Q000235:genetics / Q000378:metabolism*; D012333:RNA, Messenger / Q000378:metabolism; D051381:Rats; D017207:Rats, Sprague-Dawley; D013745:Tetanus Toxoid / Q000276:immunology*; D013997:Time Factors
D000941:Antigens; D016760:Proto-Oncogene Proteins c-fos; D012333:RNA, Messenger; D013745:Tetanus Toxoid