Increased Pro-BNP Secretion in Hypertensive Patients

Background and Aims: The precursor of the Brain Natriuretic Peptide (pro-BNP) represents a biological marker whose behavior in stress condition can reveal the beginning of a condition of chronic heart failure in patients at risk. The objective of our work was to evaluate the behavior of pro-BNP after hydrosaline overload on a sample of hypertensive patients.

Methods: The authors have evaluated the incretory stimulation of brain natriuretic peptide in a group of 13 patients with arterial hypertension. All of the individuals underwent a hydrosaline overload 20% of plasmatic value. Blood samples for pro-BNP determination were obtained from the antebrachial vein at time 0, 2nd hour, 4th hour, 7th hour and 10th hour. The same procedure was applied upon a control group of healthy individuals. The study was repeated after 7 months in 18 hypertensive patients. All of the individuals underwent a hydrosaline overload 25% of plasmatic value. Statistics were calculated with intra-group and intergroup analysis.

Results: The results obtained showed an increase in the secretion of pro-BNP which became important after 4 hours from the first examination in the group of hypertnsive patients. No modifications were observed in healthy group. In the second phase of the study, the results become more statistically significant than in the first part of the study. The most interesting result is the difference in secretion of pro-BNP between the hypertension group and control group which occurs earlier in respect to the first part of the study. Moreover, there is an increased production of pro-BNP between the patients with hypertension non-dippers in respect to the dippers.

Conclusions: The authors hypothesized that the increase of secretion of pro-BNP during arterial hypertension could be considered as a compensatory phenomenom linked to intolerance toward hydrosaline overload and if so, it can be due to a molecular pathology of the renal tubule and/or to a molecular pathology of the competent cells of cardiac muscle. This phenomenom seems particularly to be evidenced in non-dipping hypertension category of patients in which the cardiovascular risk is very high. Our study contributes to confirm that dynamic tests are more useful tools than static tests in exploring the organ reserve function.