The effect of an inhibitor of gut serotonin (LP533401) during the induction of periodontal disease

BACKGROUND AND OBJECTIVE

LP533401 is an inhibitor of tryptophan hydroxylase 1, which regulates serotonin production in the gut. Previous work indicates that LP533401 has an anabolic effect in bone. Thus, we hypothesized that inhibition of gut serotonin production may modulate the host response in periodontal disease. In this study, we aimed to analyze the effects of LP533401 in a rat periodontitis model to evaluate the role of gut serotonin in periodontitis pathophysiology.

MATERIAL AND METHODS

Twenty-four rats were divided into three groups: treated group (T: ligature-induced periodontal disease and LP533401, 25 mg/kg/d) by gavage; ligature group (L: ligature-induced periodontal disease only); and control group (C: without ligature-induced periodontal disease). After 28 d, radiographic alveolar bone support was measured on digital radiographs, and alveolar bone volume fraction, tissue mineral density and trabeculae characteristics were quantified by microcomputed tomography in the right hemi-mandible. Left hemi-mandibles were decalcified and alveolar bone loss, attachment loss and area of collagen in the gingiva were histologically analyzed.

RESULTS

Significant difference between the L and C groups was found, confirming that periodontal disease was induced. We observed no difference between the T and L groups regarding alveolar bone destruction and area of collagen.

CONCLUSION

LP533401 (25 mg/kg/d) for 28 d does not prevent bone loss and does not modulate host response in a rat model of induced periodontal disease.

[Assessment of third-degree congenital atrioventricular block by ergometric tests]

PURPOSE

To analyse the use of the exercise testing as the method of initial evaluation, following a prognostic indicative of patients with congenital complete heart block.

METHODS

Five patients were analysed (3 men and 2 woman) with ages between 7 and 34 years (mean = 22.8). The patients were submitted to a treadmill exercise testing using the Bruce protocol 1 and symptom limited.

RESULTS

In all patients the atrial frequency increased from a median of 74.40 bpm in the basal to 155.20 bpm in the maximum effort; the atrial chronotropism was a little below that calculated based on the age of the patients. The median of the ventricular frequency in the maximum effort was 94.80 bpm, very different from that foreseen and showing a deficit of ventricular chronotropism. The median consumption of oxygen was 35.68ml0(2)/Kg/min. In one patients (20%) there was not any change in the ventricular frequency with the effort, in 3 (60%) complex ventricular arrhythmia arise during the effort and in one (20%) a definitive ventricular pacemaker was implanted.

CONCLUSIONS

The exercise testing is a simple method of initial evaluation, providing information as chronotropism, functional capacity and the presence of arrhythmias, that can be very useful in the evaluation of prognostic. The presence of complex ventricular arrhythmias during the exercise is indicative of a more regular follow-up.

[Intrapericardial lipoma]

A 27 year-old female patient presented with atypical chest pain. 2-D echocardiogram and thorax computed tomography revealed intrapericardial tumor. The patient was operated on for removal of the tumor, which turned out to be two isolated lipomas. The patient had a rapid postoperative recuperation.