الفهرس 
REVIEW OF LITERATUREOnly 14 pages are availabe for public view
 |  | from | 199 |  |  |
| | | from | 199 | | |
Abstract
The present investigation is a controlled experimental study that aims to evaluate the
micro- and ultrastructural differences caused by nicotine and electronic cigarette refill liquid in
rat tongue and the possible effects of administration of a combination of Vitamin C and E.
Forty adult male rats weighting about 200-300 grams were used in this study. The animals
were randomly divided into 5 groups.
• Control group: 8 rats injected daily with saline intraperitoneally for 5 weeks.
• Nicotine (N) group: 8 rats injected with 0.75 mg/kg nicotine daily for 5 weeks.
• Electronic cigarette (EC) group: 8 rats injected daily with refill liquid of electronic cigarette
containing 0.75 mg/kg of nicotine for 5 weeks.
• Nicotine and vitamins (N plus V) group: 8 rats injected daily 0.75 mg/kg nicotine for 1 week.
On day 8, they were supplied with combination of Vitamin C 300 mg/kg and Vitamin E 60
mg/kg by orogastric gavage, 1 hr after nicotine injection (for 4 weeks).
• Electronic cigarette and vitamins (EC plus V) group: 8 rats injected daily 0.75 mg/kg
nicotine of electronic cigarette liquid for 1 week. On day 8, they were supplied with the
combination of vitamin C 300 mg/kg and vitamin E 60 mg/kg by orogastric gavage, 1 hr
after electronic cigarette liquid injection (for 4 weeks).
The results obtained from this study were divided into:
1. Light microscopic examination of dorsal surface of the tongue
The control group showed normal organization of filiform, fungiform and circumvallate
papillae. Normal configuration of taste buds was seen as well. Both N and ECs groups showed
obvious disorganization in the cellular structures of the dorsal lingual papillae. Taste buds lost
147
their structural characteristics. On the other hand, both groups treated with vitamins showed
promising results and revealed maintenance of histological features of both the papillae and the
taste buds.
2. Light microscopic examination of ventral surface of the tongue
Control group showed normal epithelial organization and thickness. Meanwhile,
deleterious effects were observed in EC and N groups, where both showed loss of normal
epithelial stratification. Moreover, in some areas, atypical epithelial nodular budding and
invasion into lamina propria were seen. On the other hand, both vitamins-treated groups showed
preservation of epithelial thickness, no detachment of the overlying keratin layer along with
maintenance of its regular thickness all over the epithelial surface.
3. Histomorphometry results
• The mean epithelial surface area of the dorsal surface:
The results showed significant increase in epithelial SA in nicotine plus vitamin group and
electronic cigarettes plus vitamins group groups when compared with nicotine group and
electronic cigarette groups respectively.
• The ratio between surface area of taste buds and surface area of epithelium:
There was no significant difference in this ratio between the control group and nicotine plus
vitamins group. However, there was significant difference between control and electronic
cigarette group, nicotine group along with electronic cigarette plus vitamins group.
• The mean epithelial surface area of the ventral surface:
The results showed significant decrease in N group and EC group when compared to control
group. No significant difference was found between control, (N plus V) or (EC plus V)
groups.