Angiotensin II induces the expression of c-fos mRNA in the central nervous system of the rat.
We have investigated the effects of intracerebroventricular injections of angiotensin II in conscious rats on the expression of c-fos messenger RNA (mRNA) in the caudate nucleus, hypothalamus, midbrain and brainstem using semi-quantitative polymerase chain reaction and Northern Blots. RNA analysis revealed the presence of c-fos transcripts in the midbrain and brainstem following icv injections of ANG II. ANG II (1, 10, 100 ng) induced a substantial increase in c-fos mRNA in the brainstem which was significant after 10 ng ANG II, and less after 100 ng. This effect was time-dependent being detectable within 15 minutes and maximal after 60 minutes. This ANG II-induced c-fos mRNA expression was totally inhibited by icv pretreatment with the ANG II-AT1 receptor antagonist, losartan. Our data show for the first time that stimulation of central periventricular AT1 receptors induces the expression of c-fos mRNA in the brain. Thus, ANG II, in addition to its short-term regulatory actions, can participate through transcription factors in neuroplastic processes.
Lebrun
C J
CJ
Department of Pharmacology, University of Heidelberg, Germany.
Möllenhoff
E
E
Bao
G
G
Culman
J
J
Unger
T
T
D000804:Angiotensin II / Q000008:administration & dosage / Q000494:pharmacology*; D057911:Angiotensin Receptor Antagonists; D000818:Animals; D001713:Biphenyl Compounds / Q000494:pharmacology; D001921:Brain / Q000187:drug effects* / Q000378:metabolism*; D001933:Brain Stem / Q000378:metabolism; D018076:DNA, Complementary / Q000235:genetics; D015870:Gene Expression / Q000187:drug effects; D016762:Genes, fos / Q000187:drug effects*; D007093:Imidazoles / Q000494:pharmacology; D007276:Injections, Intraventricular; D019808:Losartan; D008297:Male; D008636:Mesencephalon / Q000378:metabolism; D016133:Polymerase Chain Reaction; D012333:RNA, Messenger / Q000235:genetics* / Q000378:metabolism*; D051381:Rats; D017208:Rats, Wistar; D013777:Tetrazoles / Q000494:pharmacology
D057911:Angiotensin Receptor Antagonists; D001713:Biphenyl Compounds; D018076:DNA, Complementary; D007093:Imidazoles; D012333:RNA, Messenger; D013777:Tetrazoles; D000804:Angiotensin II; D019808:Losartan