Immunohistochemical localization of epidermal growth factor receptors in the liver of normal and streptozotocin-induced diabetic rats

Background: Diabetes mellitus is a metabolic disease characterized by hyperglycemia, which affects different tissues including the liver. Epidermal growth factor receptor [EGFR] family is one of the tyrosine kinase receptor families that regulate liver pathophysiology

Aim of the work: This study aimed to demonstrate the histological and EGFR immunohistochemical changes that occur in the liver of streptozotocin [STZ]-induced diabetic rat

Materials and methods: Twenty male albino rats divided into two groups, group I [control] and group II [diabetic], were used. Diabetes was induced in the animals in group II by a single intraperitoneal injection of STZ [40 mg/kg]. Five rats from each group were sacrificed 2 and 4 weeks after the STZ injection. Blood samples were collected for detection of serum glucose and insulin levels. Paraffin sections of the liver were prepared and stained with H and E, periodic acid Schiff, Masson's trichrome stains, and immunohistochemical stain using anti-EGFR antibody

Results: Diabetes mellitus was associated with marked congestion of central veins, blood sinusoids, and hepatic veins. Hepatocytes showed degenerative and fatty changes, especially in the periportal regions. Four weeks after induction of diabetes, signs of hepatic regeneration such as large binucleated hepatocytes were observed in the pericentral regions. Control livers showed strong positive EGFR immunoreactivity in hepatocytes, mainly in the periportal and pericentral regions, and in the bile duct epithelium. A marked decrease in EGFR immunoreactivity was observed in the livers of diabetic rats

Conclusion: Diabetes mellitus is associated with marked hepatic congestion, degenerative and fatty changes in the hepatocytes, and decreased hepatic EGFR immunoreactivity

Effect of ageing on albino rat female prostate [paraurethral glands]: a histological, immunohistochemical and morphometric study

Introduction: The prostate is not a gland exclusive to males, also being an organ of the female genital system

Aim of the work: The aim of this study was to detect histological, immunohistochemical and morphometric changes associated with ageing in female paraurethral glands [PUGs]

Materials and methods: Forty female rats were divided into two groups: adult group and aged group; each group comprised 20 rats. PUGs of both groups were removed, paraffin sections were obtained and stained with H and E, Mallory trichrome, periodic acid schiff, anti-alpha smooth muscle actin and anti-Ki67 immunostains, and then studied morphometrically

Results: The adult gland was formed of two lobes located on both sides of the urethra and showed large and small acini with wide lumens that contained periodic acid schiff-positive secretions. The acini were lined by cubical and/or columnar epithelium of two types: secretory and basal cells. Also, a few collagen fibres, thick periacinar smooth muscle layers and a few Ki67-positive cells were observed. Aged gland showed disarrangement of acinar epithelium, with formation of alveolus-like structures. Stroma was more vascular, with the appearance of newly developed acini and inflammatory infiltrate. Statistically, aged gland showed a highly significant increase in the number of acini, height of acinar epithelium, area% of collagen and Ki67 immunoexpression. In addition, a highly significant decrease in the area of acini, and a significant decrease in the acinar nuclear area and thickness of periacinar smooth muscle layers were detected

Conclusion and recommendation: Ageing of female prostate [PUG] was associated with abnormal histological and morphometric changes similar to those occurring in male prostate and this could adversely affect the health and quality of women's life. Therefore, further studies are needed to elucidate processes that maintain homeostasis of this gland

Effect of Nigella sativa on pancreatic beta-cell damage in streptozotocin-induced diabetic rats: histological and immunohistochemical study

Diabetes mellitus is a metabolic disease characterized by chronic hyperglycemia. Nigella sativa [NS] is a medical plant used as a natural remedy for a variety of illness. The aim of this study was to determine the effect of NS on pancreatic beta-cell damage and serum levels of glucose and insulin in streptozotocin [STZ]-induced diabetic rats and to correlate these effects with the immunohistochemical changes. Forty-five male albino rats were used in this study. The animals were divided into three groups: group I [control], group II [diabetic], and group III [diabetic with NS]. Diabetes was induced in group II and III animals by a single intraperitoneal injection of STZ, 40mg/kg. Group III animals were given NS oil [0.2ml/kg/day]intraperitoneally for 4 weeks. Five rats from each group were sacrificed 2 days, and 2 and 4 weeks after STZ injection. Blood samples were collected for detection of serum glucose and insulin levels. Paraffin sections of the pancreas were prepared and stained with H and E stain and immunohistochemical stain using anti-insulin antibody. After STZ injection, the pancreatic islets appeared shrunden and showed degerative changes and negative or weak positive insulin immunoreactivity. The serum level of insulin was decreased with elevation in the serum glucose concentration. NS injection improved the morphology of the islets, which nearly reverted to their normal size and structure with increased insulin immunoreactivity. NS also increased the lowered insulin and decreased the elevated glucose concentrations. NS has a protective effect on pancreatic beta-cell damage and improves serum levels of insulin and glucose in STZ-induced diabetic rats

Age-related changes in the ocular lens of the albino rat: a light and scanning electron microscopic study

The eye lens is a minute organ with a complex structure that plays an indispensible role in the process of vision. The study was conducted to detect-age related structural changes that occur in the rat ocular lens and to correlate these changes with the development of senile cataract. Fifteen male albino rats were used in this study. They were divided into three groups: young, adult, and aged [1, 6 and 18 months, respectively]. The animals' lenses were removed, dissected, and processed for light and scanning electron microscopy. The width, thickness, and number of lens fibers were assessed using an image analyzer. Statistical analysis of data was carried out using analysis of variance and the Student t-test. In H and E stained sections, the lens of aged rats was seen to be covered by a thick capsule and had a double layer of epithelial cells. The aged lens showed marked disorganization and vacuolation of nuclear fibers. Scanning electron microscopic study revealed irregularities of the lateral borders of the cortical fibers, folding of their surfaces, and few ball and socket interlocking patterns. The nuclear fibers showed microplicae with a decrease in their cross-sectioned areas. Statistical analysis revealed a significant increase in the number and width of the aged nuclear lens fibers and as significant decrease in their thickness, compared with younger ones. Lens fibers undergo some structural changes as a result of aging in the form of irregularities in shape and arrangement, thinning and compaction. These changes could be correlated to age-related optical problems such as senile presbyopia and cataract

Pancreatic stellate cells and alcohol induced chronic pancreatitis in albino rats: histological and immunohistochemical study

Pancreatic stellate cells [PaSCs] are myofibroblast-like cells found in the areas of pancreas that have exocrine function. The aim of the present work was to study the pancreatic stellate cells in the exocrine pancreas and to explain their role in pancreatic fibrosis associated with chronic alcoholic pancreatitis. Forty adult male rats were used in this study. The animals were divided into two groups; control and experimental. The experimental group was given alcohol by intragastric tube daily for 8 weeks. At the end of the experiment the animals were sacrificed and the pancreatic tissue was taken, processed and semithin and paraffin sections were obtained. Paraffin sections were stained with H and E, Mallory trichrome and immunohistochemical stains for detection of alpha smooth muscle actin [alpha-SMA] in PaSCs. Eight weeks after alcohol administration, the pancreatic tissue was traversed by thick connective tissue septa. The interlobular ducts were thickened, distorted and dilated. Some pancreatic acini were distorted, dilated and showed vacuolation and degeneration of their acinar cells. PaSCs were detected in three main sites like in control pancreas; periacinar, periductal and perivascular, but they showed an apparent increase in their number, decrease in their lipid droplets and transformtion into myofibroblast like cells with marked expression of alpha-SMA especially in the fibrotic areas. From the present work it was concluded that the cells which were detected seem to be the pancreatic stellate cells which could play an important role in the development of pancreatic fibrosis associated with alcoholic chronic pancreatitis. Therefore, understanding the biology of PaSCs may offers potential therapeutic targets for the treatment and prevention of these diseases