Expression of the c-Fos Gene in Spinal Cord and Brain Cells in Rats Subjected to Stress in Conditions of Exposure to Various Types of Halothane Anesthesia

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Neuroscience and Behavioral Physiology, Vol. 34, No. 4, 2004Expression of the c-Fos Gene in Spinal Cord and Brain Cells in

Rats Subjected to Stress in Conditions of Exposure to Various

Types of Halothane AnesthesiaN. S. Novikova,1 T. B. Kazakova,1V. Rogers,2 and E. A. Korneva1Translated from Rossiiskii Fiziologicheskii Zhurnal imeni I. M. Sechenova, Vol. 88 No. 11, pp. 13781387,

November, 2002. Original article submitted February 27, 2002, revised version received April 22, 2002.The influences of different treatments on the expression of the c-fos gene in the spinal cord and brain

(hypothalamus) was studied in rats using various types of anesthesia. Synthesis of c-Fos-like proteins

occurred only in the spinal cord in conditions of constant 1.5% halothane anesthesia. Use of induction

anesthesia with 1.5% halothane allowed detection of c-Fos-like protein expression in cells of the rat spinal

cord (lumbar segments) and brain, both when animals were placed in a hammock and when mechanical

pain stimulation or electromagnetic irradiation of the skin with UHF currents were applied. The pattern of

brain structures reacting to mechanical pain stimulation with expression of c-Fos-like protein was identified. This type of stimulation was shown to induce increases in the quantity of c-Fos-positive cells in the

lateral hypothalamic area (LHA), the ventromedial (VMH) and dorsomedial (DMH) hypothalamic nuclei,

and in the ventral hypothalamic area (AHA) by 116%, 167%, 101%, and 157% respectively as compared

with controls. Skin irradiation with UHF currents decreased the intensity of mechanical pain stimulationinduced synthesis of c-Fos-like protein in most structures (LHA, VMH, DMN, and AHA by 32.8%, 29%,

15%, and 33% respectively). Only induction halothane anesthesia allowed identification of hypothalamic

structures reacting to mechanical pain stimulation and the modifying effects of irradiating the skin with

UHF currents on the intensity of these reactions.KEY WORDS: rats, c-Fos immunoreactivity, spinal cord, brain, anesthesia, stress.Investigators are currently paying particular attention

to the analysis of brain structures involved in responses to

stress. One of the tools for addressing the functional state

of neural cells during exposure to various types of stimulus

is analysis of the expression of immediate and early

response genes; c-fos is a member of this family. Proteins

of the c-Fos family control the transcription of a whole

series of inducible genes [8], including genes encoding

cytokines, in cells...