Abstract 089: Periodontitis Accelerates The Onset Of Arterial Hypertension In SHR, While The Electrical Activation Of The Carotid Sinus Nerve Delays The Beginning Of The Increase In Blood Pressure.

Abstract

Background: We demonstrated that electrical stimulation of thecarotid sinus nerve (CSN) has a protective effect on the development ofPeriodontitis (PER). However, whether PER accelerates the onset ofhypertension in SHR is unknown. If this is true, it could be expected that theactivation of the CSN would retard the onset of hypertension. Objective: To evaluate whether PER accelerates the onset of hypertension inSHR; and whether the electrical stimulation of the CSN in SHR would delay theonset of this outcome. Methods: Three weeks old male SHRs were implanted with electrodes aroundthe CSN for daily electrical stimulation (3V; 1 ms; 30Hz; 10 minutes per day, fortwo weeks), combined with bilateral ligation of the lower first molar with a silksuture for PER induction. Besides, PER induction was combined with theadministration, p.o., of Porphyromonas gingivalis (strain W83) injected threetimes a week. The femoral artery of a five-week-old SHR was cannulated, and 24hours later, with the animals awakened, the systolic (SAP), diastolic (DAP), andmean (MAP) arterial pressure were recorded. Control SHR (SHAM) was notexposed to PER. Results: Five weeks old control SHR (SHAM) did not have installed arterialhypertension. However, when the SHR were submitted to PER, they alreadyexhibited a higher arterial pressure at five weeks, when compared to the SHAMgroup (SAP PER 150±4 vs. SHAM 124±3 mmHg, n=8, p≤0.001; DAP PER 103±5 vs. SHAM 85±5 mmHg, n=8, p≤0.05; MAP PER 119±4 vs. SHAM 98±4 mmHg,n=8, p ≤0.01). Nevertheless, the stimulation of the CSN prevented this increasein blood pressure in the five weeks old SHR submitted to PER (PAS SHR PERstim. 130±4 vs. SHAM 124±3 mmHg; PAD SHR PER stim. 84±3 vs. SHAM 85±5mmHg; PAM SHR PER stim. 99±4 vs. SHAM 98±4 mmHg, n=8, p>0, 05). Conclusion: PER accelerated the onset of arterial hypertension in SHR withinfive weeks. However, the activation of the baroreceptor and chemoreceptor reflexes through the electrical stimulation of the CSN in SHR exposed to PERdelayed the onset of arterial hypertension.