Tehran University Medical Journal

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With the intention of research of various methods of epithelial tissue culture we've studied five French Albino rabbits with an average of 8 weeks. In order to evaluate and control growth and proliferation of autologus cultured tissue samples were obtained on 1st, 5th and 8th days. After fixation of these samples and passing them through various processes, histologic sections were prepared. These sections were stained with H-E and studied by light microscope, we succeeded in developing the original donor surface by 18 times.

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Background: Epidural fibrosis (EF) is a part of normal physiological tissue response to laminectomy and it may be an important cause of failed back surgery syndrome (FBSS). The objective of this study was to evaluate the effect of using gel foam after laminectomy on reduction of epidural fibrosis.

Methods: In this prospective study forty five rabbits were recruited. The cases undergone bilateral laminectomy at the L4 and L5 lumbar levels under an approved surgical protocol. After eight weeks the rabbits were sacrificed and the spinal segments from L3 to L6 were removed en bloc. The amount of scar tissue at the laminectomy defect was scored. The fibroblast and inflammatory cell counts were also compared between two groups.

Results: In this study 55% of group A rabbits were placed in grade 0 or I, grade II fibrosis could be detected in the remaining 45%. In group B these amounts were 73.7% and 26.3% respectively, which no significant statistical difference could be detected between two arms (p=0.189). Comparing the quantity of fibroblasts 40% of group A rabbits were recognized as grade I and the other 60% as grade II and grade I fibrosis was discovered in 42.1% of group B rabbits, while other 57.9% suffered from grade II fibrosis, again no significant statistical difference could be attributed between two arms (p=0.576). Also comparing inflammatory cell counts detected in the specimens no significant statistical difference could be detected either (p=0.465).

Conclusion: According to this study using gel foam during the laminectomy surgery in rabbits has no obvious effect in reducing post laminectomy epidural fibrosis after eight weeks of follow-up.

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Background: The effects of growth hormone (GH) on bone density in healthy adults is controversial. This study was performed to evaluate the effects of GH administration on bone density under controlled conditions in healthy adult rabbits.

Methods: Twenty healthy adult New Zealand white rabbits of both sexes were included in the study. The rabbits were divided into two groups. The experiment group received human GH and the controls placebo for three months. The density of femur and humerus were measured at proximal epiphysis, mid shaft and distal epiphysis by radiography, aluminum step-wedge and appropriate software. Measurements were performed in five stages, once before and four times after the administration of GH or placebo, with 3-week intervals.

Results: The mean concentration of serum insulin-like growth factor I (IGF-I) increased significantly after GH administration (P<0.05) in the experiment group. Bone density generally increased in all regions except the distal epiphysis of femur in the test group, but significant difference were only seen in the midshaft of femur in comparison to the controls (P<0.05). In the second stage, bone density decreased slightly in all regions except distal epiphysis of femur, but it increased in the next stages.

Conclusion: GH can increase bone density (mostly cortical bone) in adult rabbits. According to the similarities seen between growth hormone effects in rabbit and humans, this study suggests rabbits as a model for studying GH effects on bone density in acromegaly, growth hormone deficiency and even in healthy adult humans.

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Background: Propolis (bee glue) is a resinous substance obtained from bee hives living on various plant sources. The purpose of this study was to evaluate the effects of ethanol extract of propolis (EEP) on the experimentally induced Candidial keratitis in rabbits. Methods: The alcoholic extract of propolis was prepared by 80% ethyl alcohol. After suppressing the immune system of 24 male rabbits, experimental Candida albicans keratitis was induced in the animals under local anesthesia and sterile conditions. The animals were later divided into four groups including the control or glycerin group and a nystatin and two 500 and 1000µg/ml EEP groups. Treatment continued for 21 days and after sacrificing the animals by humane methods, histopathological samples of the rabbits’ eyes were prepared. Results: Keratitis was developed in the eyes of all rabbits a week after the yeast inoculation. In the control group in which animals received glycerin, keratitis persisted until day 21. Clinical signs of keratitis disappeared in the Nystatin and 1000µg/ml EEP groups after 14 and 21 days, respectively. The clinical signs of keratitis partially ameliorated in the animals receiving 500µg/ml EEP. Histopathological examination revealed no differences between groups receiving nystatin or 1000µg/ml EEP. Conclusion: It is concluded that, ethanol extract of propolis could completely treat Candida albicans keratitis in 1000µg/ml concentrations. This extract can be used as a safe antifungal agent against Candida albicans and it is a good substitute for synthetic antifungal agents like nystatin.