Differential time course of angiotensin-induced AP-1 and Krox proteins in the rat lamina terminalis and hypothalamus

Department of Pharmacology, University of Kiel, Hospitalstrasse 4, 24105 Kiel, Germany; Department of Cell Biology, German Cancer Research Center, Im Neuenheimer Feld 280, 69120 Heidelberg, Germany; II. Institute of Physiology, University of Heidelberg, Im Neuenheimer Feld 326, 69120 Heidelberg, Germany
Neuroscience Letters (Impact Factor: 2.03). 01/1998; DOI: 10.1016/S0304-3940(97)00957-9

ABSTRACT We studied the time course of expression of the inducible transcription factors (ITF) c-Fos, FosB, c-Jun, JunB, JunD, Krox-20 and Krox-24, induced by a single intracerebroventricular injection of angiotensin II, in the subfornical organ (SFO), median preoptic nucleus (MnPO) paraventricular nucleus (PVN) and supraoptic nucleus (SON). c-Fos and Krox-24 were expressed rapidly in neurons of all four areas but completely disappeared after 4 h. FosB showed a delayed but persistent expression between 4 h and 24 h in the MnPO and PVN. c-Jun was induced in the MnPO, SFO and PVN after 1.5 h and in the SON after 4 h. JunB was selectively expressed in the MnPO and SFO and the level of JunD did not change. The expression of the pre-existing transcription factors SRF, CREB and ATF-2 which contribute to the transcriptional control of jun, fos and krox genes, was not affected by Ang II. Thus, we could show for the first time that an acute stimulation of AT receptors results in continual changes in ITF expression over 24 h.

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