Muhammed Eyüp Altunkaynak

Effects of diabetes and ovariectomy on rat hippocampus (A biochemical and stereological study)

Oxidative stress is one of the main reasons of both menopause and diabetes. So, it plays crucial role in the pathogeneses of that condition and disease. Therefore, the objective of the present study was to investigate the effects of menopause and diabetes upon the hippocampus using a rat model. Adult female Sprague Dawley rats (n = 24) were allocated randomly as follows; control (C group) ovariectomized (O group), diabetic (D group) and ovariectomy plus diabetic groups (DO group) (n = 6; in each group), respectively. For evaluating the results, tissue biochemistry and stereological analysis were made. Biochemistry results (lipid peroxidase (LPO); catalase (CAT); superoxide dismutase (SOD); total glutatyon (GSH); and myeloperoxidase (MPO) values) in Group C-DO were determined as 12.27, 21.88, 23.08 and 29.90 nmol/gr tissue; 59.3, 70.06, 69.7 and 78.1 mmol/min/mg tissue; 174.2, 156.4, 159.7 and 154.6 mmol/min/mg tissue; 3.63, 3.61, 4.21 and 3.97 nmol/mg tissue; and 5.05, 5.68, 5.58 and 6.19 µmol/min/mg tissue, respectively. Moreover, both menopause and diabetes led to change of lipid profiles. There were significant differences between the control and other groups (Group C and D-DO) (p < 0.01) and among experimental groups (p < 0.01) in terms of neuron number. When the volumes of the hippocampus were compared, there were no significant differences between the all groups (P > 0.05). At this point, we suggested that diabetes could aggravate deleterious effects of ovariectomy.

Inhalation of mercury vapor can cause the toxic effects on rat kidney

Dental amalgam has been used in dentistry as a filling material. The filler comprises mercury (Hg). It is considered one of the most important and widespread environmental pollutants, which poses a serious potential threat for the humans and animals. However, mercury deposition affects the nervous, cardiovascular, pulmonary, gastrointestinal, and especially renal systems. In most animals’ species and humans, the kidney is one of the main sites of deposition of mercury and target organ for its toxicity. In this study, the effects of mercury intake on kidney in rats were searched. For the this purpose; we used 24 adult female Wistar albino rats (200 g in weight) obtained from Experimental Research and Application Center of Atatürk University with ethical approval. Besides, they were placed into a specially designed glass cage. Along this experiment for 45 days, subjects were exposed to (1 mg/m3/day) mercury vapor. However, no application was used for the control subjects. At the end of the experiment, kidney samples were obtained from all subjects and processed for routine light microscopic level and stereological aspect were assessed. Finally, according to our results, mercury affects the histological features of the kidney. That means, the severe effects of mercury has been shown using stereological approach, which is one of the ideal quantitative methods in the current literature. In this study, it was detected that chronic exposure to mercury vapor may lead to renal damage and diseases in an experimental rat model.

Stereological and histological analysis of the developing rat heart.

With 9 figures and 1 table

Effect of prenatal exposure to diclofenac sodium on the male rat arteries: a stereological and histopathological study

In this study, we investigated the morphometric and histological alterations of the aorta, brachial, and femoral arteries in 4- and 20-week-old rats that were prenatally exposed to diclofenac sodium (DS). For this purpose, pregnant rats were divided into three groups: control, saline injected, and drug treated. Beginning from day 5 after mating through day 15 of pregnancy, saline or DS (1 mg/kg daily) was intraperitoneally injected into groups 2 and 3. No injection was given to the rats in the control group. After spontaneous delivery, male offspring were obtained. At the end of weeks 4 and 20, vessel samples were removed. After dissection and routine histological preparation, histopathological and stereological investigations were made. Our results indicate that both saline and DS application lead to a decrease in the mean volume fraction of tunica media in all vessel walls, but result in an increase of the same fraction of lumen to the whole vessel wall, especially in 4-week-old rats. Elastic fibers of the vessel wall were affected by DS treatment, because a decrease of the elastic fiber was observed in this group. Finally, in light of our findings, we suggest that DS or saline may lead to vascular changes (i.e., vasodilatation or vasoconstriction) in rats that are prenatally subjected to increased volume of maternal blood resulting from injection.

Effect of mercury vapor inhalation on rat ovary: Stereology and histopathology.

Mercury, an environmental contaminant, is a risk factor for health in whole living organisms. In this study, we investigated whether mercury vapor (HgO) inhalation has an effect on rat ovary.

A stereological and histopathological study of the effects of exposure of male rat testes to mercury vapor

Mercury is ubiquitous in the environment; it is an occupational pollutant and a potential toxicant. We investigated the effects of exposure of rat testes to mercury vapor (Hg0). Twelve male rats were divided into two groups of six: the rats of the Hg0 group were exposed to mercury (1 mg/m3/day) in a chamber for six weeks; the control group rats were housed under the same conditions without exposure to Hg0. After the experimental period, the testes were removed, sections of testis were evaluated histopathologically after hematoxylin and eosin staining, and stereologically using the Cavalieri principle and optical fractionator methods. We found significant decreases in the total volume of testis, diameters of seminiferous tubules and total volume of seminiferous tubules. Significant decreases were detected in the numbers of Sertoli cells, spermatogonia, spermatocytes and spermatids of the Hg0 group compared to the control group. In the Hg0 exposed group, spermatogenic cells were degenerated and seminiferous tubules were atrophied.

Stereological Evaluation of the Kidneys of Anencephalic and Normal Fetuses

The aim of this study is to test the glomerular and other quantitative parameters of kidneys of anencephalic fetuses and comparing those to “normal” fetuses. In this study, 20 kidneys of human fetuses (5 boys and 5 girls of anencephalic fetus, and 5 boys and 5 girls of normal fetus), at gestational ages of 25–30 weeks, were examined. This study is based on two basic research methods: one is a conventional anatomical measurement at the macroscopical level; the other is a design-biased stereological method at the microscopical level. Physical dissector and Cavalieri principle were used to estimate the total and numerical density of glomerulus and the volume of kidney, respectively. The results of the two types of investigation were compared based on anencephalic/normal and boy/girl kidneys at both the macroscopical and microscopical levels. There was no significant difference found between the quantitative features of kidneys (volume of kidneys and mean number and/or height of glomerulus) belonging to anencephalic and normal fetuses. The results of this study suggest that anencephalic fetuses did not differ from normal fetuses in respect of kidneys.

Development of the Cranial Nerves

Abstract The cranial nerves are 12 pairs of nerves that emerge from the brain stem to innervate the face, sensory organs, and some regions of the body. During development of the cranial nerves, a number of unique features including neural tube, neural crest and glial cells, specialized paired sense organs, thickenings of the head ectoderm known as cranial placodes, and also cranial sensory ganglia are needed. Moreover, many signaling molecules play important roles when cranial nerves are developing. Here we describe the development of the cranial nerves and their components and summarize development of the central nervous system, signaling molecules, and developmental abnormalities of the cranial nerves.