HEMORRHAGE-INDUCED PRODUCTION OF FOS IN NEURONS OF THE LAMINA TERMINALIS - ROLE OF ENDOGENOUS ANGIOTENSIN-II

Hypotensive haemorrhage increased the production of Fos, a marker of c ell activation, in cells of the subfornical organ (SFO) and the organu m vasculosum of the lamina terminalis (OVLT) as well as in the supraop tic (SON) and paraventricular (PVN) nuclei in conscious rats. Pretreat ment with captopril (100 mg/kg i.p.) inhibited the production of Fos i n cells of the SFO and OVLT but did not reduce the concentration of Fo s-positive cell nuclei in the PVN and SON. The results suggest that th e production of Fos in the SFO and OVLT induced by the haemorrhage is probably due to elevated levels of circulating angiotensin II.