Nassar C A, Nassar P O, Andia D C, Guimarães M R, Spolidorio L C
Department of Periodontology Araraquara Dental School, University of State of São Paulo, Araraquara, São Paulo, Brazil.
Oral Dis. 2008 Jan;14(1):67-72. doi: 10.1111/j.1601-0825.2006.01354.x.
Tacrolimus, an immunosuppressive drug used in organ transplantation, has been reported not to induce gingival overgrowth. However, prevalence studies are limited, and the methods used for assessing gingival overgrowth varies among studies.
The purpose of this study was to evaluate the effects of up to 240 days of tacrolimus therapy on gingival tissues of rats.
Rats were treated for 60, 120, 180 and 240 days with daily subcutaneous injections of 1 mg/kg body weight of tacrolimus. After histological processing, the oral and connective tissue, volume densities of fibroblasts (Vf), collagen fibers (Vcf) and other structures (Vo) were assessed in the region of the lower first molar.
After 60 and 120 days of treatment with tacrolimus, gingival overgrowth was not observed. The gingival epithelium, connective tissue, as well as the values for Vf, Vcf, and Vo were similar to those of the control rats (P>0.05). After 180 and 240 days of the treatment, gingival overgrowth was associated with a significant increase in the gingival epithelium and connective tissue as well as an increase in the Vf and Vcf (P<0.05).
Within the limits of the experimental study, it may be concluded that the deleterious side effects of tacrolimus on the gingival tissues of rats may be time-related.
他克莫司是一种用于器官移植的免疫抑制药物，据报道不会引起牙龈增生。然而，患病率研究有限，且不同研究中评估牙龈增生的方法各异。
本研究旨在评估长达240天的他克莫司治疗对大鼠牙龈组织的影响。
大鼠每日皮下注射1mg/kg体重的他克莫司，分别治疗60、120、180和240天。经过组织学处理后，在右下第一磨牙区域评估口腔和结缔组织、成纤维细胞体积密度（Vf）、胶原纤维（Vcf）和其他结构（Vo）。
他克莫司治疗60天和120天后，未观察到牙龈增生。牙龈上皮、结缔组织以及Vf、Vcf和Vo的值与对照大鼠相似（P>0.05）。治疗180天和240天后，牙龈增生与牙龈上皮和结缔组织的显著增加以及Vf和Vcf的增加相关（P<0.05）。
在本实验研究的范围内，可以得出结论，他克莫司对大鼠牙龈组织的有害副作用可能与时间有关。
