الفهرس 
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Abstract
Summary
Aflatoxins are a group of mycotoxins produced by a large number of Aspergillus species. It is a naturally occurring toxic metabolite produced by the fungi (Aspergillus flavus), a mold that can be found on several food products. These molds are able to colonize a wide range of crops both in the field and during long-term storage. The type called Aflatoxin B1 is the most toxic and the most prevalent in food. chronic exposure to AFB1 was found to induce pathological and oxidative damage in body tissues. The oxidative stress caused by AFB1 is one of the underlining mechanisms for AFB1-induced cell injury.
Rosemary is a medicinal edible plant that is full of phenolic compounds that possess potent antioxidant activity. Thus is able to protect the cell components against oxidative damage by neutralizing the damaging effects of free oxygen radicals.
So the present study was conducted to investigate the effect of AFB1 on the submandibular salivary gland of Albino rats. In addition, to examine the possible therapeutic effect of Rosemary extract. Structural and ultrastructural investigations were performed on the examined groups.
Materials and methods:
Thirty-five healthy adult male Albino rats, three months old and weighing 200-220 gm were used in this study. They were divided into three groups:
group A ( Control group): consisted of 14 rats that were subjected to intraperitoneal injection of 9% saline and were equally subdivided into 2 subgroups:
• group A1: served as a control for 4 weeks.
• group A2: served as a control for 6 weeks.
group B: consisted of 14 rats that were equally subdivided into 2 subgroups:
• group B1: subjected to intraperitoneal injection of AFB1 (2 mg/kg) once daily for 4 weeks.
• group B2: subjected to intraperitoneal injection of AFB1 (2 mg/kg) once daily for 4 weeks and then stopped for the following 2 weeks.
group C: consisted of 7 healthy adult Albino rats that were subjected to intraperitoneal injection of AFB1 (2 mg/kg) once daily for 4 weeks followed by intraperitoneal injection of Rosmarinus Officinalis extract (400mg/kg) for 2 weeks.
At the end of the experimental periods, the rats’ submandibular salivary glands of the right and left sides were dissected out. Those of the right side were fixed in 10% neutral buffered formalin, washed, processed, embedded in paraffin, then sectioned. Six microns thick sections were stained with Hematoxylin and eosin stain for structural examination to find out any possible microscopic changes. The specimens of the left sides were used for ultrastructural examination with TEM.
Results:
a) Histological results:
Histological sections of submandibular salivary glands of rats injected with AFB1 lacked the normal architecture. The acini appeared to be shrunken with an apparent decrease in size and were filled with many cytoplasmic vacuoles. Ducts lost their normal histological features and showed many degenerative changes with many cytoplasmic vacuolations and crescent-shaped nuclei. The connective tissue surrounding the ducts showed areas of destruction with dilated and congested blood vessels. Moreover, the group that received AFB1 followed by two weeks of recovery period showed no signs of improvement. However, the group that received AFB1 followed by Rosemary extract showed that the glands almost regained their normal appearance with a minimum degree of atrophic and degenerative changes among the acini and the ducts.
b) Ultrastructural results:
AFB1 group ultrastructural results revealed that the gland suffered from degeneration in its acinar and ductal cells. Nuclei of both acinar and ductal cells were pyknotic, darkly stained with loss of continuity of the nuclear membrane which was often irregular. Some nuclei of the intercalated duct exhibited a crescent-shaped appearance. The cytoplasm of the serous acinar cells, GCTs, striated and excretory duct cells revealed numerous large vacuolations. rER were dilated and mitochondria showed signs of degeneration manifested as loss of their cristae and some vacuolations. A decrease in desmosomal junctions between cells was encountered in some areas. Ultrastructure examination of submandibular glands of rats treated with both AFB1 followed by Rosemary extract revealed that the glands almost regained its normal architecture. Nearly normal rER and mitochondria were observed. Very few, cytoplasmic vacuolations were found. Normal desmosomal junctions between ductal cells were present.
Conclusions
• Submandibular salivary glands of rats subjected t