possible correlation between the testicular structure and short photoperiod exposure in young albino rats: light and electron microscopic study

Light is considered as the first ecological factor affecting primary productivity. Several studies have attempted to relate between seasonal changed environmental light factors and the reproductive system. The influence of environmental light on the anatomy and physiology of different organs has been investigated intensely in a different species. Therefore, this research was designed to examine the effects of a short duration of light exposure on the histological structures of rat testes. Eighteen young male albino rats were divided into control [I] and experimental [II] groups. They were kept for 8 weeks in separate cages. The rats in group I were exposed daily to a normal lighting cycle of 12 h light and 12 h darkness. Light was provided by a 20-W 4-ft fluorescent lamp. Group II was exposed daily to 4 h of light and 20 h of darkness. They were housed in a small room. Its windows were covered with a black cotton material. At the end of the experiment, all rats were anaesthetized with ether, and their testes were dissected out and processed for light and electron microscopic examination. In group II, spermatogenic cells of some seminiferous tubules appeared separated and exfoliated. The other tubules were destroyed, with acidophilic hyaline material. Loss of germ cells was confirmed by a significantly low sperm count. Some germ cells showed a vacuolated cytoplasm and disrupted intercellular bridges with the formation of giant cells. Sertoli cells showed active phagocytic capacity with the appearance of multivesicular bodies. Hormonal assay showed a low significant testosterone level; this was supported by the presence of inactive spindle-shaped Leydig cells. The present study confirmed that rats were structurally and functionally photosensitive. Therefore, the changes in the normal photoperiod could influence their reproductive functions

Effect of streptozotocin-induced diabetes mellitus on the cerebellar cortex of adult male albino rats: histological and immunohistochemical study

Diabetes mellitus is a common metabolic disorder with well-known serious secondary complications. It is also associated with central nervous system damage. This damage is characterized by impairment in brain functions, with neurochemical and structural abnormalities. To clarify the effects of streptozotocin-induced diabetes on the histological structure of the cerebellar cortex of adult rats. Twenty adult male albino rats were used in this study, randomly divided into three groups. Group I was the control group; group II received a single intraperitoneal injection of 0.1 ml saline; and group III received a single intraperitoneal injection of streptozotocin at a dose of 60 mg/kg freshly dissolved in 0.1 ml saline. After 8 weeks, the cerebellum was dissected and processed for light and electron microscopic examinations and also for glial fibrillary acidic protein [GFAP] to demonstrate the astrocytes. Morphometrical and statistical analyses were carried out. In group III, degenerative changes were observed in neurons. Mitochondrial alterations and disarrangement of myelin sheaths with increased area of myelinated axons were observed. Dispersed presynaptic vesicles in swollen axonal terminals were also observed. However, there was good evidence of gliosis, which was supported by a significant increase in the number of GFAP astrocytes. The cerebellar cortex was particularly susceptible to hyperglycemia-induced oxidative stress and could have contributed toward the neuronal damage and increased astrocyte activity

Effects of perinatal nicotine exposure on the development of albino rat's alveoli with special reference to the role of the vascular endothelial growth factor

Nicotine is one of the most toxic and addictive agents in cigarette smoke. Maternal cigarette smoking may affect lung development and maturation of the fetus. Recently, it has been reported that blood vessels promote alveolar growth during development and contribute toward the maintenance of alveolar structures throughout postnatal life. The aims of this study were to determine the effects of perinatal nicotine exposure on the histological structures of the developing alveoli of offspring with special reference to the role of vascular endothelial growth factors [VEGF]. Ten healthy pregnant rats were divided equally into control [I] and treated [II] groups. Rats of group II were subjected to a daily subcutaneous injection of 1 mg/kg of nicotine from the seventh day of gestation until the end of the experiment. Their offspring were subdivided into two subgroups at 2 and 21 postnatal days. At the time of sacrifice, all rats were anesthetized with ether and lung samples were processed for light and electron microscopic examination. Also, an immunohistochemical study was carried out for VEGF. The alveolar diameter, thickening of interalveolar septa, number of vacuolated interstitial cells, and the surface area of VEGF immunoexpression were determined and analyzed statistically. In the nicotine-exposed groups, widening in alveoli and thinning of interalveolar septa in the offspring were observed. Also, the same offspring showed a reduction in VEGF immunoexpression. All these results were confirmed statistically especially at 3 weeks of age or at the time of weaning. Also, swelling in pneumocyte type I and deformed blood air barriers with a subsequent statistical increase in the number of vacuolated interstitial cells [pneumocyte type II] were observed. In the current work, it was found that perinatal exposure to nicotine altered lung development, an effect that may be mediated by decreased VEGF. Thus, avoidance of maternal smoking during pregnancy and lactation is highly recommended

Role of hepatic stellate cells in fibrogenesis in a model of pomegranate-treated fatty liver induced by junk food in male albino rats immunohistochemical and electron microscopic study

Hepatic fibrogenesis is a common result of liver injury. It is believed to be a critical factor that leads to hepatic failure. A critical event in fibrogenesis is activation of hepatic stelate cells [HSCs]. The aim of this investigation was to study the role of HSCs in figrogenesis in a model of pomegranate juice [PJ]-treated fatty liver induced by junk food using immunohistochemical and electron microscopic study. Thirty young male albino rats were divided into control [1] and experimental [II] groups. Group II was further divided into two subgroups: II-a [junk food] and II-b [pomegranate juice + junk food]. After 8 weeks, blood samples were collected for detection of leptin and tumour necrosis factor alpha TNF-alpha. Then half of the liver samples were processed for light microscopic examination, whereas the other half were prepared for electron microscopic examination. Praffin sections were stained using H and E, glial ibrillary acid protein, alpha -smooth muscle actin, TNF- alpha, and transforming growth factor -beta-1 TGF-beta1. Morphometric and statistical studies for assessing immunoexpression were carried out. HSC's markers glial fibrilar acid protein and alpha -smooth muscle actin and cytokines TNF- alpha and TGF- beta1 in subgroup II-a showed strong positive immunoexpression. Electron microscopic study showed activated - HSCs containing granules and collagen fibrils. Proliferative and myofibroblast -HSCs were also seen in the same group. Subgroup II-b showed a nonsignificant increase in immunoexpression of HSC s markers and cytokines. However, only activated -HSCs were seen. Immunoexpression of HSC markers and cytokines may be used as an indicator for liver fibrosis. Presence of different types of HSCs in fatty liver explains their role in fibrosis. Further experimental and clinical studies directed toward inhibiting the activity of HSC may delay or prevent liver fibrosis occurs in many pathological conditions

Harmful effects of arsenic on the cerebral cortex of adult male albino rats: light and electron microscopic studies

Arsenic is a common environmental contaminant that is available worldwide. It has been reported that human arsenic exposure causes nervous system disturbances such as polyneuropathy and neurobehavioral deficits. The purpose of this work was to describe the histological changes induced by arsenic in the cerebral cortex of adult male albino rats and discuss its possible mechanisms of action. Twenty adult male albino rats were equally classified into control [I] and experimental [II] groups of 10 animals each. Rats of group II were intraperitoneally injected with 2mg/kg/day of sodium arsenite for 20 days. Samples from the temporal lobes of the cerebrum were taken and processed for light and electron microscopic examination. Features of neurodegeneration such as shrunken, irregular, and darkly stained nuclear and degenerating organelles were observed in arsenic-treated rats. Good evidence of gliosis and disrupted blood-brain barrier were also detected. The adult brain is particularly susceptible to arsenic-induced oxidative stress and contributes to the neurodegenerative lesions

Effect of titanium dioxide [TiO2] as a color additive on the testes, sperms and chromosomes of male albino rats

Titanium dioxide [TiO2] is one of the top 50 produced substances for use around the world. 70% of all [TiO2] produced is used as pigment in consumer products such as plastics, health, beauty aids and other personal care product that we use. Toothpaste products use [TiO2] to get that desirable bright white color as do many other products such as lotions, creams, shave foam, cosmetics, sunscreen lotions and more. Food products such as sour cream, cottage cheese [via the cheese dressing] ice cream and other dairy products use a small quantity of the pigment to attain that familiar brightwhite coloration. The aim of this study was to evaluate the histopathological effect of 1/20 of LD50 of [Ti02] on the testes, sperms and chromosomes of albino rats and its relation to the duration of its adminstration. Forty male albino rats had been divided into four groups, ten rats for each. The first was served as a control group, the second was gavaged by [TiO2] 600mg/kg daily for 4weeks. The third was gavaged with same dose of [TiO2] for 8 weeks and the forth group was gavaged by same dose of [Ti02] for 12 weeks. Each rat's group were sacrificed after each duration, testes specimens were taken and stained with Haematoxylin and Eosin. The sperms were examined for number, viability, motility and shape abnormalities. For chromosomal study, rats from each group were anaesthetized and the bone marrow cells were obtained by Rabello-Gay and Ahmed method. Microscopic examination of the testicular specimens, revealed disorganized germinal epithelium with abnormal mitotic figures and apoptotic cells. Sperm analysis showed that sperm count, viability and motility were decreased and the sperm anomalies were increased. Chromosomal analysis of bone marrow cells showed many aberrations as, chromatid deletions, ring chromosomes, chromosomal gaps, dicentric chromosomes, clumping of the chromosomes and polyploidy. All the former revealed that the histopathological changes and abnormalities caused by [TiO2] had been aggravated by prolonged duration of administration

Evaluation of the hepatotoxic effects of polyethylene and butylated hydroxy toluene in adult male albino rats

Plastic is used in contact with nearly all packaged foods; plastic is made by combining many toxic synthetic man-made chemicals by a process called polymerization. FDA Office of Food Additive Safety assuming that all plastics migrate toxins into the food they contact. Butylated hydroxy toluene [BHT] is one of additives in LOPE [low-density polyethylene] and HOPE [high-density polyethylene]. Migration into water and food substances have been measured for this BHT antioxidant, generally at higher temperatures than experienced in normal use, there is considerable loss of antioxidants especially with fatty or oily foods so, study for biochemical and histopathological changes induced by Polyethylene and BHT on the liver of adult male albino rats using light and electron microscopes has done as following: Fifty albino rats were divided into five groups. 1[st] group rats served as control, 2[nd] group was gavaged daily with 0.5 ml of com oil [vehicle], 3rd group was administered with polyethylene pellets mixed to food by 1:20 daily, 4[th] group was gavaged with BHT by 1120 of LOSO equal 400 mg/kg/day in com oil, and the 5[th] group was gavaged by combination of polyethylene and BHT at same doses as 3[rd] and 4[th] groups. At the end of experiment which lasts for 12 weeks, all rats were anaesthetized and blood samples were collected for analysis of Alpha Feto Protein CAFP] serum level and liver function tests. Animals were sacrificed, specimens from liver were taken, and prepared for histopathological examination through light and electron microscopes. The study revealed that: There was significant increase of Alanine transaminase [ALT] and Aspartate transaminase CAST] with lowering in alkaline phosphatase level among Polyethylene, BHT and combination of BHT with Polyethylene administered groups compared to control group while AFP level showed significant elevation in both BHT and combined [polyethylene and BHT] group compared to control and polyethylene groups. These biochemical changes had been proved by histopathological examination, liver cells showed cellular infiltration around central vein with dilation and congestion of the vein and blood sinusoids, lobular necrosis with fatty infiltration. Ultrustructurally, liver cells showed muddy cytoplasm contained electro lucent vacuoles, electron dense mitochondria with loss of or few microvilli in bile canaliculi and sinusoids. This study concluded that, BHT gave the most significant toxic effect on liver of albino rats than ingestion of pure polyethylene while toxic effect was more prominent by using combination of both agents