Calcitonin gene-related peptide (
alpha CGRP) and
galanin (GAL) are
peptides known to participate in central mechanisms of blood pressure control. Nonetheless, variations in the synthesis of the
peptides in response to a hypertensive challenge are not well described, specially using a model, which allows acute and chronic analyses. In this study, we have employed in situ hybridization to analyse changes in
mRNA expression of
alpha CGRP and GAL in the nucleus tractus solitarii (NTS), hypothalamic paraventricular nucleus (PVN) as well as petrosal and nodose ganglia after
aortic coarctation-induced
hypertension in rats. Acute (2h) and chronic (3 and 7 days) analyses were performed in order to evaluate the involvement of both
peptides in different periods of
hypertension. The analysis of relative
mRNA levels showed significant differences between
sham-operated and aortic coarcted hypertensive rats.
alpha CGRP mRNA expression was decreased 2h (40%) and 3 days (42%) in nodose and petrosal ganglia, respectively, after coarctation. No changes in CGRP
mRNA signal were seen in the NTS and PVN in the analysed periods. GAL
mRNA expression was decreased in the NTS (19%) and PVN (55%), 3 and 7 days, respectively, after coarctation-induced
hypertension. No changes in GAL
mRNA expression were observed in petrosal and nodose ganglia following
aortic coarctation. Data suggest that
alpha CGRP and GAL may participate in the mechanisms involved in the establishment/maintenance of
hypertension induced by
aortic coarctation. Acute changes might be involved with the adaptation to the hypertensive state, while changes at the chronic phase might be related to counteraction of
hypertension.