Antigen-induced activation of hypothalamic cells (assessed by expression of the c-fos gene)

• Published in: Neuroscience and behavioral physiology Vol. 32; no. 5; pp. 523 - 528
• Main Authors: Nosov, M A, Barabanova, S V, Glushikhina, M S, Kazakova, T B, Korneva, E A
• Format: Journal Article
• Language: English
• Published: United States Springer Nature B.V 01-09-2002
• Subjects: Animals; Antigens - immunology; Hypothalamus - cytology; Hypothalamus - immunology; Hypothalamus - metabolism; In Situ Hybridization; Male; Neuroimmunomodulation; Proto-Oncogene Proteins c-fos - genetics; Proto-Oncogene Proteins c-fos - metabolism; Rats; Rats, Sprague-Dawley; RNA, Messenger - metabolism; Tetanus Toxoid - immunology; Time Factors
• ISSN: 0097-0549; 1573-899X
• DOI: 10.1023/A:1019863707510

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.