Restraint stress-induced expression of <i>Fos</i> and several related genes in the hypothalamus of the hypertensive ISIAH rats

Abstract

Stress can play a significant role in the development of arterial hypertension and many other complications of cardiovascular diseases. Considerable attention is paid to the study of the molecular mechanisms involved in the body’s response to stressful influences, but there are still many blank spots in understanding the details. ISIAH rats model a stress-sensitive form of arterial hypertension. ISIAH rats are characterized by genetically determined enhanced hypothalamic-adrenal-cortical and sympathetic adrenomedullary systems activity, which suggests a functional state of increased stress reactivity. In the present study, for the first time, the time course of the Fos and several related genes’ expression was studied in the hypothalamus of adult male hypertensive ISIAH rats after exposure to a single restraint stress of different duration (30, 60, and 120 minutes). The results of the study showed the activation of Fos transcription with a peak 1 hour after the onset of restraint stress. The dynamics of Fos gene activation coincides with the dynamics of blood pressure increase after stress. Restraint stress also alters the transcription of several other genes encoding transcription factors (Jun, Nr4a3, Jdp2, Ppargc1a) associated with the development of cardiovascular diseases. Since Fos induction is a marker of brain neuron activation, we can conclude that increased stress reactivity of the hypothalamic-pituitary-adrenocortical and sympathoadrenal systems of hypertensive ISIAH rats during short-term restriction is accompanied by activation of hypothalamic neurons and increased blood pressure level.