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Abstract-We investigated the role of angiotensin II (Ang II) and endothelin-1 (ET-1) in transgenic (mREN2)27 rats, a model of the monogenic renin-dependent form of severe hypertension and cardiovascular disease. Four-week-old heterozygous male transgenic (mREN2)27 rats (nϭ24) were matched according to body weight (BW) and blood pressure (BP) and randomly allocated to receive a placebo (group P), the mixed endothelin type A and B receptor antagonist bosentan (100 mg/kg BW PO, group B), the Ang II type 1-specific receptor antagonist irbesartan (50 mg/kg BW PO, group I), or the endothelin type A-selective antagonist BMS-182874 (52 mg/kg BW PO, group BMS). After 4 weeks of treatment, during which BW and BP were measured weekly, animals were euthanized, and the heart, left ventricle, right ventricle, adrenal gland, brain, and kidney were weighed. The plasma levels of adrenocortical steroids were measured by high-performance liquid chromatography. The tension responses of ET-free segments of the thoracic aorta to 5ϫ10 Ϫ6 mmol/L phenylephrine, 60 mmol/L KCl, and cumulative doses of ET-1 were assessed. The density of ET-1 receptor subtypes in the aorta and vascular structural changes in the mesenteric arterioles (100 to 200 m ID) were also measured with autoradiography and myography, respectively. Compared with all other groups, group I rats showed significantly (PϽ0.001) lower systolic BP (group I, 161Ϯ8 mm Hg; group P, 269Ϯ23 mm Hg; group B, 275Ϯ17 mm Hg; and group BMS, 254Ϯ21 mm Hg), left ventricular weight (2.28Ϯ0.15 versus 3.71Ϯ0.26, 3.38Ϯ0.27, and 3.96Ϯ0.51 mg/g BW, respectively), tension responses to vasoconstrictors, and normalized media thickness of the mesenteric arterioles (22.3Ϯ0.6 versus 25.3Ϯ0.5, 25.5Ϯ0.7, and 24.1Ϯ1.5 m, respectively). Compared with levels in group P (78Ϯ25 pmol/mL), plasma aldosterone levels were significantly decreased in group B (51Ϯ11 pmol/mL) and group I (40Ϯ16 pmol/mL). Thus, endogenous ET-1 and Ang II contribute to the regulation of aldosterone, but only Ang II is crucial for the development of hypertension and related target organ damage via the Ang II type 1 receptor. Endogenous Ang II does not appear to enhance cardiovascular production of ET-1 in this model of hypertension within the time span of our experiment. 8 by acting on Ang II type 1 (AT 1 ) receptors linked to activation of transcription via activator protein-1/ protein kinase C-mediated mechanisms. 7-11 ET-1 might be involved in mediating renin-dependent hypertension and also cardiovascular damage (CVD), because it was found to contribute to the hypertrophic response to Ang II. 10 -14 However, data concerning the interactions between Ang II and ET-1 in hypertension are conflicting (see Reference 4 for a review). Studies in rats with Ang II infusion and administration of bosentan suggested that ET-1 could importantly contribute to renal and systemic vasoconstriction and thus to arterial hypertension. 15,16 Bosentan was also reported to prevent the increase in heart weight, albuminuria, and carotid medial thickness (MT)...

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During ageing process, multiple changes occur on nervous tissue composed of cells and extracellular matrix. Changes on nervous tissues are usually known as degenerative changes on axon structure and connective tissue covering the nerve such as a decrease in the number of fibre or general structural changes. For this purpose, we have studied age-dependent ultrastructural changes in the rat oculomotor nerve with electron microscopy and also demonstrated collagen structure of the neural sheaths with immunohistochemical techniques. This study was conducted in Gazi University Faculty of Medicine, Department of Anatomy with a total of nine Wistar albino rats. We observed strong collagen type I immunoreactivity in endoneurium and slight to moderate reactivity in fibroblast cytoplasm in 3-month- and 12-month-old groups and mild reactivity in 24-month-old group. Collagen type IV immunoreactivity was stronger in endoneurium and perineurium in the 3-month- and 12-month-old groups compared with collagen type I and fibroblast cytoplasm showed a very strong reactivity. On the other hand, in the 24-month-old group, there was slight reactivity in endoneurium and a strong reactivity in perineurium. NGF staining showed moderate to strong reactivity on Schwann cells of the 3-month-old group. The immunoreactivity decreased in the 12-month- and 24-month-old groups. In the 3-month-old rat group, Schwann cell cytoplasm, mitochondrial structure and neurofilaments were normal. In the 12-month-old group, there were no changes in organelle distribution, mitochondrial structure and neurofilaments, but there was an increase in the connective tissue. An inconsiderable number of degenerated myelinated nerves were observed. We detected an important decrease in the collagen type I immunoreactivity, which could suggest that the endoneurium, perineurium and epineurium are less resistant to the age-related collagen loss and that the peripheral nerve is protected by a weaker barrier in the old group. The collagen type IV immunoreactivity was significantly decreased with age. NGF synthesis decreases with age because of Schwann cell structural degeneration or for different reasons. Thus, this could explain the diminished capacity of regeneration and damage of the myelination of the peripheral nerve.

The gluteal region is an important secondary sexual character itself and it has its place in the concept of the beauty in all communities. Interestingly, as far as we know, there is not any previous study addressing gluteal region morphology in an objective way in the aesthetic surgery literature. The aim of this study was to define the changes of the gluteal region morphology with aging and weight gain. Beside body weight, a total of five distances between predetermined anatomic points in gluteal region were measured on randomly selected 115 female volunteers, with their age ranging from 17 to 48 years (mean 22.7). All the records were analyzed by a correlation matrix using computer-based SPSS 7.5 program. As women grow older, the width of the gluteal region decreases and the gluteal sulcus elongates laterally and inferiorly. Contrary to aging, with weight gain the gluteal region becomes wider as the gluteal sulcus gets shorter. Although the subject does not sound new, our study is the first, documenting the changes in morphology of the gluteal region in relation to weight gain and aging in an objective way.

Objective: To describe a horseshoe kidney, a congenital anomaly of the upper urinary tract. Clinical Presentation: A case study of horseshoe kidney harvested from a 62-year-old cadaver at Gazi University Medical School is presented. Results: The right and left kidneys were fused at their lower poles by a parenchymal isthmus located ventral to the abdominal aorta and formed a U-shape with two unequal arms.The isthmus of the ectopic kidney was placed obliquely to the left at the level of the fourth and fifth lumbar vertebra. The left kidney was larger and longer than the right one. The kidneys were supplied by three renal arteries arising from the abdominal aorta. Two arteries on the right side supplied blood of the two kidneys, while the third artery that directly originated from the aorta, above the origin of inferior mesenteric artery, supplied the isthmus. Venous drainage of the both kidneys and the isthmus were drained by three veins that opened independently into the inferior vena cava. The right ureter was duplicated in origin. Conclusion: This report shows that knowledge of anomalies such as this is very important in planning and conducting surgical procedures.

Objective: The purpose of this study was to use the modified Sihler’s staining technique to demonstrate detailed distribution of the rat anterior abdominal wall nerves and test the value of Sihler’s technique in demonstrating such a complex muscle-nerve relationship. Materials and Methods: The anterior abdominal walls of 5 Wistar rats were isolated by making a deep incision from the costal arches on each side down to the inguinal region and processed using a modified Sihler’s stain technique. Results: This technique was successfully applied to visualize the innervation of the anterior abdominal wall muscles of the rat. The segmental nerves of T₆–L₁ and their terminal branches were shown and possible motor and sensory fibers identified. Conclusions: This technique is valuable in understanding the complex nature of final branching of the nerve endings, and it may be useful for studying experimental nerve models.