Abstract
Urodilatin (UD) and uroguanylin (UGN) have been implicated in the regulation of salt
and water homeostasis, particularly in the balance handling of salt intake. In this
sense, the aim of the present work was to study the main effects of these peptides
in kidneys from animals subjected to high NaCl (2%) intake, during 10 days in metabolic
cages. The control group received only normal water, whereas the treated group drank
2% solution of NaCl (NaCl 2%). In addition, we studied effect of subthreshold UD (0.14 nM)
and UGN (0.06 μM) doses in NaCl 2% after a 30-min control period. Kidney perfusion
was performed with Krebs–Henseleit containing 6 g% bovine albumin previously dialyzed.
The effects of UD (0.14 nM) promoted reduction of PP, RVR, and UF in the NaCl 2% group.
We also observed an increase in %TNa+ and %TCl−. The main effects of UGN in NaCl 2% were increase in PP, UF, and GFR, followed by
a reduction in %TNa+ and %TCl−. After an increased intake of salt, physiological pathways are activated and regulated
in order to eliminate excess sodium. In this study, we observed that in a subthreshold
dose, UD does not promotes natriuresis and diuresis, suggesting that UGN is an important
hormone in inducing salt excretion in a chronic salt overload. Therefore, the effects
herein described may play a contributory role in the regulation of kidney function
after ingestion of salty meals.
Key words
urodilatin - uroguanylin - natriuresis
