Angiotensin II (Ang II) AT<sub>1</sub> receptors are involved in the regulation of the stress response. In adult male rats, acute restraint increased AT<sub>1A</sub> mRNA in paraventricular nucleus. Repeated restraint increased AT<sub>1A</sub> mRNA and AT<sub>1</sub> binding in paraventricular nucleus and AT<sub>1</sub> binding in subfornical organ and median eminence. AT<sub>1B</sub> and AT<sub>2</sub> receptors were not expressed in brain areas involved in the stress response. Acute restraint increased anterior pituitary AT<sub>1A</sub> mRNA and AT<sub>1</sub> binding and decreased AT<sub>1B</sub> mRNA. During repeated restraint, the increase in AT<sub>1A</sub> mRNA in the anterior pituitary was maintained, but AT<sub>1B</sub> mRNA and AT<sub>1</sub> binding returned to normal levels. In adrenal zona glomerulosa, AT<sub>1B</sub> mRNA, AT<sub>1</sub> binding, AT<sub>2</sub> mRNA and AT<sub>2</sub> binding decreased during acute restraint. Receptor mRNA and binding returned to normal after repeated stress, with the exception of rebound increase in adrenal zona glomerulosa AT<sub>2</sub> mRNA. In adrenal medulla, AT<sub>1A</sub> mRNA increased and AT<sub>2</sub> mRNA decreased during acute restraint. AT<sub>1A</sub> mRNA remained increased during repeated restraint, while alterations in AT<sub>2</sub> mRNA were no longer present. Expression of AT<sub>1A</sub>, AT<sub>1B</sub> and AT<sub>2</sub> receptors in the hypothalamic-pituitary-adrenal axis is tissue specific and is different in acute and repeated stress. Increased brain, pituitary and adrenomedullary AT<sub>1A</sub> receptor expression correlates with hypothalamic-pituitary-adrenal axis stimulation, supporting the hypothesis of Ang II, through selective AT<sub>1A</sub> receptor stimulation, as an important determinant of the acute and repeated stress response. Decreased adrenal zona glomerulosa and anterior pituitary AT<sub>1B</sub> receptors during acute stress can be interpreted as compensatory to increased stimulation by Ang II. There may be additional roles for adrenal AT<sub>2</sub> receptors during acute stress, possibly related to interaction or cross-talk with AT<sub>1</sub> receptors.