Effects of systemic administration of nicotine on capillaries in rat oral mucosa

Abstract

This study examined the reaction of the local vasculature of the oral mucosa in 16 Sprague Dawley rats receiving systemic nicotine delivered (1.5 mg/kg/day) via subcutaneous minipumps for 24 h or 2wk. Control animals received saline. After treatment animals were killed and biopsies taken from palate, maxillary gingiva and buccal mucosa, frozen and cryostat sections incubated to demonstrate alkaline phosphatase, which is a capillary marker. The total length of the capillary fragments in the nicotine treated groups was significantly less than of the control group. There was also a decrease in capillary height in both of the nicotine groups when compared to the control animals. This study indicates that morphologic alterations occur in the microvasculature of the oral mucosa following systemic nicotine administration. This may have implications for the role of chronic tobacco use in the etiology of oral mucosal disease, including periodontal disease.

Central nicotinic stimulation reduces vascular conductance in the gingiva in anesthetized rats

“…In smokers, gingival blood vessels tend to show stenosis and their numbers decrease (4, 5). In rats chronically nicotine‐medicated for 2 weeks, the widths of gingival blood vessels decrease (22). A similar chronic reduction by smoking of gingival blood flow would be elicited by a long‐term uptake of nicotine in humans.…”

Tobacco‐induced suppression of the vascular response to dental plaque

“…observed that a solution of tobacco smoke applied to the gingiva of dogs could suppress subsequent crevicular innate cell migration in neutrophils isolated from both healthy and inflamed sites . In nicotine‐exposed rats, both capillary length and height were noted to be reduced, compared with untreated controls, in the maxillary gingiva . Breivik et al., 2009 reported that, in ligature‐induced periodontitis in rats, nicotine administration enhanced alveolar bone loss concomitant with a reduced pro‐ and anti‐acute inflammatory cytokine response to LPS (TNF, transforming growth factor‐β, IL‐10) .…”

Effect of smoking on the gingival capillary density: assessment of gingival capillary density with orthogonal polarization spectral imaging

“…It has been observed that significantly increased levels of TNF‐ α have been detected in gingival crevicular fluid in both current and former smokers who have received treatment or no treatment for periodontal disease (Boström et al 1998a, b). In another study morphologic alteration in the microvasculature of the rat oral mucosa was observed after systemic administration of nicotine (Johnson et al 1989). In animal studies, it has been suggested that cigarette smoke has more influence on the microcirculation than just nicotine alone (Chen et al 2002).…”