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Background: Spinal cord injury (SCI) causes infertility in male patients through erectile dysfunction, ejaculatory dysfunction, semen and hormone abnormalities. Oxidative stress (OS) is involved in poor semen quality and subsequent infertility in males with SCI. The aim of this study is to examine the effects of SCI on the level of testosterone hormone. Materials and Methods: In this experimental study, we evaluated the effects of exogenous testosterone on the activity of the antioxidant enzymes superoxide dismutase (SOD) and glutathione peroxidase (GPx) as well as the levels of malondialdehyde (MDA) and protein carbonylation (PCO), as markers of OS, in 10 groups of SCI mice. Total antioxidant capacity (TAC) was determined using the 2,29-azinobis-(3-ethylbenzothiazoline- 6-sulfonic acid) (ABTS) radical cation assay. Results: Exogenous testosterone administration in mice with SCI significantly reduced SOD and GPx enzyme activities and MDA level. There was no significant decrease in PCO content. In addition, TAC remarkably increased in the sham and SCI groups not treated with testosterone but remained unchanged in all other experimental groups. Exogenous testosterone also reduced serum testosterone levels in all groups except the positive control group. Conclusion: Our cumulative data indicated that SCI could cause sterility by disturbing the plasmatic testosterone balance. The normal level of endogenous testosterone was not completely restored by exogenous testosterone administration.

Background: Seladin-1 protein protects the neural cells against amyloid beta toxicity and its expression decreased in vulnerable regions of Alzheimer's disease (AD) brains. On the other hand, changes in serum levels of S100 have been considered as a marker of brain damage in neurodegenerative diseases. Furthermore, this study was carried out to determine the relation between the change profile of serum S100β protein levels and hippocampal Seladin-1 gene expression in a rat model of sporadic AD. Methods: In this experimental study that established in Department of Neuroscience, School of Advanced Technologies in Medicine, Tehran University of Medical Science, from March 2011 to April 2013, 72 animals were randomly divided into control, 4, 7, 14, and 21days ICV-STZ/Saline administrated rats. Alzheimer's model was induced by intracerebroventricular (ICV) injections of streptozotocin (STZ) [3 mg/kg] on days 1 and 3. Serum levels of S100β and hippocampal Seladin-1 gene expression were evalu-ated in experimental groups. The initial and step-through latencies (STL) were deter-mined using passive avoidance test. Results: Serum levels of S100β were significantly different between the STZ-7 day and STZ-14 day groups in comparison with the control, saline and STZ-4 day groups. As well as, there was a significant difference between the STZ-7 day group in comparison with the STZ-14 day and STZ-21 day groups (P=0.0001). Hippocampal Seladin-1 gene expression in STZ-14 day and STZ-21 day groups significantly decreased as compared to the control, saline and STZ-4 day groups (P=0.0001). However, significant correla-tion was detected between serum S100β protein decrement and Seladin-1 down regula-tion (P=0.001). Also, the STL was significantly decreased in 21 days ICV-STZ adminis-trated rats as compared to the control or saline groups (P=0.001). Conclusion: Monitoring the changes of serum S100β protein levels by relationship with changes in hippocampal Seladin-1 gene expression can be a useful indicator of neu-ronal damage in patients with Alzheimer's disease.

Ischemic stroke is an important cause of death and disability in the world. Brain ischemia causes damage to brain cell, and among brain neurons, pyramidal neurons of the hippocampal CA1 region are more susceptive to ischemic injury. Recent findings suggest that neurotrophic factors protect against ischemic cell death. A dietary component of Rosa damascene extract possibly is associated with expression of neurotrophic factors mRNA following ischemia, so it can have therapeutic effect on cerebral ischemia. The present study attempts to evaluate the neuroprotective effect of Rosa damascene extract on adult rat hippocampal neurons following ischemic brain injury. Forty-eight adult male Wistar rats (weighing 250±20 gr and ages 10-12 weeks) used in this study, animals randomly were divided into 6 groups including Control, ischemia/ reperfusion (IR), vehicle and three treated groups (IR+0.5, 1, 2 mg/ml extract). Global ischemia was induced by bilateral common carotid arteries occlusion for 20 minutes. The treatment was done by different doses of Rosa damascena extract for 30 days. After 30 days cell death and gene expression in neurons of the CA1 region of the hippocampus were evaluated by Nissl staining and real time PCR assay. We found a significant decrease in NGF, BDNF and NT3 mRNA expression in neurons of CA1 region of the hippocampus in ischemia group compared to control group (P

Cerebral ischemic stroke is a common leading cause of disability. Flaxseed is a richest plant-based source of antioxidants. In this study, the effects of flaxseed oil (FSO) pretreatment on functional motor recovery and gene expression and protein content of neurotrophic factors in motor cortex area in rat model of brain ischemia/reperfusion (I/R) were assessed. Transient middle cerebral artery occlusion (tMCAo) in rats was used as model brain I/R. Rats (6 in each group) were randomly divided into four groups of Control (Co+normal saline [NS]), Sham (Sh+NS), tMCAo+NS and tMCAo+FSO. After three weeks of pretreatment with vehicle or FSO (0.2 ml~800 mg/kg body weight), the rats were operated in sham and ischemic groups. Ischemia was induced for 1 h and then reperfused. After 24 h of reperfusion, neurological examination was performed, and animals were sacrificed, and their brains were used for molecular and histopathological studies. FSO significantly improved the functional motor recovery compared with tMCAo+NS group (P

Introduction: Recent studies have shown that astrocytes play major roles in normal and disease condition of the central nervous system including multiple sclerosis (MS). Molecular target therapy studies in MS have revealed that connexin-43 (Cx43) and Aquaporin-4 (AQP4) contents of astrocytes undergo expression alteration. Fluoxetine had some effects in MS patients unrelated to its known antidepressant effects. Some of fluoxetine effects were attributed to its capability of cAMP signaling pathway stimulation. This study aimed to investigate possible acute effects of fluoxetine on Cx43 and AQP4 expression in astrocyte. Methods: Astrocytoma cells were treated for 24 hours with fluoxetine (10 and 20 &mug/ml) with or without adenyl cyclase (AC) and protein kinase A (PKA) inhibition. Cx43 expression at both mRNA and protein levels and AQP4 expression at mRNA level were evaluated. Results: Acquired results showed that fluoxetine with and without AC and PKA inhibition resulted in Cx43 up-regulation both in mRNA and protein levels, whereas AQP4 expression have not changed. Discussion: In conclusion, data showed that fluoxetine alone and in the absence of serotonin acutely up-regulated Cx43 expression in astrocytes that can be assumed in molecular target therapy of MS patients. It seems that cAMP involvement in fluoxetine effects need more researches.

Spinal cord injury (SCI) is a crucial complication that results in neurons degeneration. The SCI lead to triggering of secondary complications such as inflammation that in turn has a key role in neurodegeneration development. The previous studies showed that TNF-α and iNOS genes expression increased significantly after SCI. As a consequence, these genes overexpression intensify the inflammation and neuron degeneration process. In the present study, 32 male Wistar rats were chased and divided into four groups of eight. The SCI were induced in three groups and another group used as a sham. The estrogen hormone used as a therapeutic agent in rats with SCI. The results showed that injection of 10 μg/kg/12h estrogen hormone reduced the TNF-α and iNOS genes expression significantly and confirmed the role of progesterone in the reduction of inflammation reduce the inflammation. The numbers of intact neurons in Estrogen group were higher than other groups and showed that progesterone has protective effects on neuron death. The BBB test was performed and demonstrated that estrogen is an effective factor in the improvement of locomotor response. Our results suggested that estrogen hormone with anti-inflammatory activity can be an efficient agent for SCI complications therapy.

Improve in Neurogenesis with Socialization can Reduce Behaviors that are Related to Poor Prognosis in Withdrawal Period in Male Rats Morphine withdrawal period is associated with a wide variety of problems. Neurogenesis seems necessary for brain functions. Socialization is a lifelong process that helps getting behavioural norms from society. The aim of this study is to investigate if better neurogenesis in socialization can alleviate problems encountered during withdrawal period.

Purpose: To evaluate the antiulcer activities of the methanol extract of pomegranate (Punica granatum L) fruit peel using 80 % ethanol-induced gastric ulcer model in rats.Methods: Male Wistar rats, 175 - 220 g, were fasted for 48 h, but had free access to water. They were randomly divided into nine experimental groups. Ulcer was induced in the rats with 80 % ethanol. The control group animals received the same treatment as those in the test groups except that the extract treatment was replaced by administration of appropriate volume of the dosing vehicle. Histaminereceptor type-2 (H2) blocker, cimetidine (100 mg/kg, i.p.) was used as the reference drug. Oral pretreatment with three different extract doses (25, 50 and 100 mg/kg) was for 15 days, thereafter, ulcer index (UI) and inhibition were calculated.Results: The extract, at 50 mg/kg, of black fruit peel extract produced significant (p < 0.05) protective effect in rats with a preventive index of 65.87 %. Other doses were significantly protective against ethanol-induced gastric ulcer in the rats. On the other hand, north white peel was not effective (50 mg/kg) showed an ulcer index of 49.52 ± 1.99. Histopathological examination of the stomach of the ulcerated animals treated with white peel (50 mg/kg) showed severe erosion of gastric mucosa, submucosal edema and neutrophil infiltration.Conclusion: The study shows indicates the antiulcer properties of the methanol extracts of north white peel, sour summer and black peel (25, 50, 100 mg/kg) of pomegranate. Their antiulcer activity is exerted, possibly, via its high antioxidant activity.Keywords: Anti-inflammatory, Pomegranate, Punica granatum, Peel extract

Diabetes Mellitus (DM) is one of the most important metabolic disease causes in many side effects. The decrease of mental abilities and even some form of dementia followed prolonged diabetes has been reported. There are evidences that show hippocampus might be the site of neural involvement in patients with dementia followed diabetes. As hippocampus received main serotonergic efferents from brain stem raphe nuclei include dorsal raphe nucleus (DRN) and median raphe nucleus (MRN), it is possible that these efferent affected by diabetes. We used adult male Wistar rat in this study. Diabetes was induced by IP injection of streptozotocin (STZ). After 2,4 and 6 months, HRP tracing were done for the efferent from DRN & MRN to CA3 of hippocampus.HRP Positive neuron of DRN & MRN and also the distribution of these cells were study by light microscopy. Statistical analysis was done by SPSS software. Microscopic study clearly showed significant decrease in HRP positive cells population in DRN & MRN after prolonged diabetes. Based on our finding ,the changes in the neural connection between serotonergic nuclei and hippocampus followed diabetes might be one of the reasons for dementia in these patients.

The ascending serotonergic projections are derived mainly from mesencephalic raphe nuclei. Topographical projections from mesencephalic raphe nuclei to the striatum were examined in the rat by the retrograde transport technique of HRP (horseradish peroxidase). In 29 rats stereotaxically injection of HRP enzyme were performed in dorsal and ventral parts of striatum separately. The extent of the injection sites and distribution of retrogradely labeled neuronal cell bodies were drawed on representative sections using a projection microscope. Following ipsilateral injection of HRP into the dorsal striatum, numerous labeled neurons were seen in rostral portion of dorsal raphe (DR) nucleus. In the same level the cluster of labeled neurons were hevier through caudal parts of DR. A few neurons were also located in lateral wing of DR. More caudally some labeled neurons were found in lateral, medial line of DR. In median raphe nucleus (MnR) the labeled neurons were scattered only in median portion of this nucleus. The ipsilateral injection of HRP into the ventral region of striatum resulted on labeling of numerous neurons in rostral, caudal and lateral portions of DR. Through the caudal extension of DR on 4th ventricle level, a large number of labeled neurons were distributed along the ventrocaudal parts of DR. In MnR, labeled neurons were observed only in median part of this nucleus. These findings suggest the mesencephalic raphe nuclei projections to caudo-putamen are topographically organized. In addition dorsal and median raphe nuclei have a stronger projection to the ventral striatum.

Herbal therapy was the common treatment prescribed by Iranian physicians for wound healing. “Zemad” was the most ancient pharmaceutical dosage form used in Iranian Traditional Medicine (ITM) for skin diseases. In the present research, formulation of a traditionally used Poly Herbal Paste (PHP) for wound healing was performed. Moreover, the fingerprint of the product was prepared by HPTLC method for identification and quality assessment of the formulation. 3.33 % of each plant materials containing Aloe vera, Boswellia carteri and Commiphora myrrha were used in a hydrophilic base. The physical stability and rheological behavior of the formulation was evaluated. Moreover, microbiological tests was performed. Methanol fraction of A. vera, C. myrrha and B. carterri were used as standard materials in HPTLC method. Stability and rheological behavior evaluations as well as microbiological tests showed that the prepared formulation was stable towards physical changes with no growth of pathogenic microorganisms and suitable for topical application. HPTLC fingerprinting of PHP confirmed the presence of compounds corresponding to the plants used in the formula. Regarding to the antioxidant, anti-inflammatory and antimicrobial effects of the constituents of PHP, the product could be an appropriate candidate for wound healing with respect to its traditional use in ITM. In addition, HPTLC fingerprinting could be used as an applicable method for quality control assessment of the prepared formulation.

Background: One of the most important issues in medical sciences is wound healing and repair. Application of natural ingredients and herbs for treating ulcers has been in the history of human life. Nowadays, due to the lack of side effects of medicinal plants and a variety of effective compounds in plants, as well as numerous disadvantages of synthetic drugs there has been tendency to use medicinal plants in clinic. Aloe vera is an herbal drug used for treatment of dermal diseases. In this study we evaluated, effects of aloe vera on the wound healing through the microscopic techniques and cell counting. Methods: In this experimental study, sixty Wistar rats weighing 200-250 g were placed under general anesthesia and sterile conditions. Then a square shape wound with 1.5´1.5 mm dimension was made on the back of the neck. Rats were randomly divided to control and experimental group’s. Each group was divided to three subgroups with 4, 7, and 14 study days. In 1st experimental group aloe vera was used twice on the wound surface and in 2nd experimental group was used once daily and the positive control group were applied phenytoin cream 1% from the zero days of surgery. The control group did not get any treatment on the wound surface. For histological studies, during the fourth, seventh and fourteenth day’s rats were sacrificed and samples were taken from the wound area and adjacent skin. After histological staining with hematoxylin and eosin (H&E) and Masson's trichrome stains, the cells were counted, wound surface and wound healing were investigated. Results: The macroscopic and microscopic evaluation showed that wound healing increased because the fibroblast numbers in two experimental groups improved compared with control group. The percentage of wound healing on different days in the experimental and control groups were significant. Data were analyzed by using one-way ANOVA test and P< 0.05 was significant. Conclusion: Present study showed that the twice application of topical aloe vera mucilage can result in rapid wound healing in rats.

Integration is an important educational strategy in medical education. Considering this idea, the goal of the present study was to design and implementation of longitudinal and vertical integrated education of anatomy, physiology, pharmacology, neurology and neuropsychiatry subjects of brain's basal ganglia by a multidisciplinary team. Kern's approach to curriculum development was used. Participants were 20 medical students at basic science level who contribute in a 10 stations of pre-test exam at Medical School's Skill Lab. After the implementation of the module by a multidisciplinary team, post-test were done. A structured questionnaire was designed to assess student opinions about adequacy, usefulness of the module using a Likert scale with 5 categories ranging from "completely agreement" to "completely disagreement". The result of pre and post-test were also compared. Twenty questionnaires were completed, giving a 77.63% satisfaction rate. Seventy-five percent of students found it useful and appropriate at basic science level. About fifty percent of students suggested the implementation of this module for other medical students. The score of post-test was significantly (14.52 ± 0.47 vs 6.32 ± 0.62, P0.05) higher than pre-test results. The viewpoints of medical students were positive and they value the module highly. Since it is not easy to change the style we teach, these results suggest necessitate of supporting the faculty member's participation in these modules.

Vincristine (VCR) as a frequently used antimitotic agent which is commonly prescribed for wide spectrum of neoplasm, causes mixed sensorimotor neuropathy. Several evidences show lithium could be a neuroprotective agent, therefore to assess whether a pretreatment and at subtherapeutic dose it could prevent the peripheral neuropathy produced by VCR, rats were treated with VCR 0.1mg/kg i.p. for 3 alternative doses and / or lithium chloride (20mg/kg or 40 mg/kg i.p. daily from the first day to the day of sacrifice). Erythrocyte lithium concentration (ELC) and plasma lithium concentration (PLC) were measured at the seventh day of study and the day of scarification. After seventh day of lithium administration, PLC and ELC reached to a steady state at subtheraputic dose and they did not significantly change at normal housing situation. Hot plate, open field test and nerve conduction velocity were used to evaluate the sensory and motor neuropathy. Only VCR treated rats showed behavioral, electrophysiological and histological evidences of a mixed sensorimotor neuropathy by significant increase in hot plate latencies and a marked decrease in total distance moved and conduction velocities in both sensory and motor nerves. Lithium at the dose of 20mg/kg and specially 40mg/kg robustly reduced the rate of mortality, general toxicity and was able to ameliorate mixed sensorimotor neuropathy induced by VCR. These results suggest that lithium at dose of 20mg/kg and 40 mg/kg, potentially by its effects on cell survival pathways such as inhibition of glycogen synthase kinase-3 (GSK3β), can prevent both motor and sensory components of VCR neuropathy.

The biological effects of omega-3 and omega-6 fatty acids are determined by their mutual interactions. This interaction extremely affects various functions. Lower consumption of omega-3 during gestation leads to various disorders, even in hearing. We aimed to assess the effect of low omega-3/omega-6 ratios on auditory nerve conduction. In this experimental study, the auditory brainstem response test was performed on 24-day-old rat (n=14). The rats were divided into case (low omega-3/omega-6 ratio during gestation and lactation) and control groups. Variables such as P1, P3, and P4 absolute latency period, interpeaks (P3-P4, P1-P3, and P1-P4), and P4/P1 amplitude ratio were measured. We found an increased P4 omega-3/omega-6 ratio in the group with a low omega-3/omega-6 ratio (P0.05). Also, no significant difference was observed between the groups with respect to the P1-P3 interpeak latency (IPL) periods (P>0.05); while the P1-P4 and P3-P4 IPLs were significantly increased in the group with a low omega-3/omega-6 ratio (P

In Wistar rats, reproductive behavior is controlled in a neural circuit of ventral forebrain including the medial amygdala (Me), bed nucleus of the stria terminalis (BNST) and medial preoptic area (MPOA) via perception of social odors. Diabetes Mellitus (DM) is a widespread metabolic disease that affects many organs in a variety of levels. DM can cause central neuropathies such as neuronal apoptosis, dendritic atrophy, neurochemical alterations and also causes reproductive dysfunctions. So we hypothesized damage to the nuclei of this circuit can cause reproductive dysfunctions. Therefore in this project we assessed diabetic effect on these nuclei. For this purpose neuron tracing technique and TUNEL assay were used. We injected HRP in the MPOA and counted labeled cells in the Me and BNST to evaluate the reduction of neurons in diabetic animals. Also, coronal sections were analyzed with the TMB histochemistry method. Animals in this study were adult male Wistar rats (230 ± 8g) divided to control and 10-week streptozotocin-induced diabetic groups. After data analysis by SPSS 16 software, a significant reduction of HRP-labeled neurons was shown in both Me and BNST nuclei in the diabetic group. Moreover, apoptotic cells were significantly observed in diabetic animals in contrast to control the group. In conclusion, these alterations of the circuit as a result of diabetes might be one of the reasons for reproductive dysfunctions.

Background: Clinicians have been searching for ways to obtain "super normal" wound healing. Honey is a traditional remedy for the treatment of infected wounds. We aimed to evaluate the wound contraction and antibacterial properties of locally produced Thyme honey on managing full-thickness wounds in vivo. Methods: This experimental study was conducted in 2015, in Department of Pharmacology, School of Pharmacy, Tehran University of Medical Sciences, Tehran, Iran on 54 adult male Wistar rats weighing 200-250 gr, and ages of 3-4 months. A square 1.5*1.5 wound was made on the back of the neck. The rats were divided into control and two experimental groups. Additionally, the control and experimental groups were separated into three subgroups corresponding to 4, 7, and 14 d of study. The control group did not receive any treatment. For histological studies, samples were taken from the wound and adjacent skin. This tissue was examined using histological staining (H&E). Wound surface and wound healing were evaluated. Data were analyzed by using one-way ANOVA with post hoc Tukey test and (P

Cranial parameters and cephalic indices are used to evaluate the racial and gender differences. The aim of this study was to assess the cephalic indices, to classify the type of cranium and to determine the relationship between the horizontal cephalic index and cranial parameters among Iranian medical students. This study was done on 200 medical students (100 males and 100 females) with an age range of 18-30-year-old. Head length, head breadth, and auricular height were measured by using a standard spreading caliper. Then cephalic indices were calculated for the classification of cranial type. The linear regression was used for examining the relationship between the horizontal cephalic index and head length, head breadth and auricular height. The results of this study showed that the mean of the horizontal, vertical, and transverse cephalic index in total students were 83.51±6.85, 85.58±5.85 and 102.77±6.35 cm, respectively. According to this result, the predominant head shapes in total students were brachycephalic, hypsicephalic and acrocephalic types. In this study, there was a strongly negative correlation between horizontal cephalic index with head length (r=-0.744, P=0.000), moderate positive correlation between horizontal cephalic index with head breadth (r=0.512, P=0.000) and weakly negative correlation between horizontal cephalic index with auricular height (r=-0.205, P=0.004). The data of the present study can be beneficial in craniofacial reconstruction, clinical diagnosis, and forensic applications.

One of the most frequent complications of diabetes is diabetic peripheral neuropathy. Hyperglycemia would result in the advancement of this condition over a period of time. The most effective way in preventing diabetic neuropathy is regular control of glucose. In this study; we evaluated the effects of lithium onstreptozocin (STZ)-induced diabetic neuropathy in rats. Diabetic neuropathy was created 7 weeks after administration of STZ (45 mg/kg). Lithium was added to drinking water (450 mg/l) for 7 weeks and its plasma level after this period of time was 0.17±0.02 mmol/l. Levels of adenosine triphosphate (ATP) in dorsal root ganglion (DRG) neurons, oxidative stress parameters, open-field activity test and morphological analysis were assessed in this investigation. Currentresults showed significant elevation of oxidative stress biomarkers, reduction of ATP, abnormal morphology of DRG neurons and decrease of total distance moved in rats with STZ-induced diabetic neuropathy. The alterations in mentioned parameters were considerably restored by lithium treatment. These findings provide evidence for protective effects of lithium on STZ-induced diabetic neuropathy.

Oxidative stress plays a major role in the pathogenesis of Alzheimer's disease (AD) of sporadic origin. The expression of DHCR24 (Seladin-1), marker for neuronal oxidative stress and degeneration, has been reported to be altered in the brains of AD patients. In the present study, we investigated the effect of trimetazidine (TMZ) on the hippocampal oxidative parameters and the expression of DHCR24 (Seladin-1) in an animal model of sporadic AD. Male rats were pre-treated with TMZ (25 mg/kg) after which injected with intracerebroventricular-streptozotocin (ICV-STZ)/Saline. Following 2, 7 and 14 days, animals of different groups were sacrificed with their brain excised to detect the hippocampal lipid peroxidation, superoxide dismutase (SOD), catalase activity, DHCR24 (Seladin-1) expression and possible histopathological changes. ICV-STZ administration induced significant oxidative changes in the hippocampus. Meanwhile, TMZ pre-treatment showed to ameliorate the oxidative stress, which was demonstrated by a significant rise in the hippocampal SOD and catalase activity, as well as a significant decrease in the malondialdehyde (MDA) level. TMZ administration also increased the expression of DHCR24 (Seladin-1) gene in the hippocampus. In conclusion, our findings indicated a neuroprotective effect of TMZ possibly related to its antioxidant activity resulting in the up-regulation of DHCR24 (Seladin-1). Such TMZ effects may be beneficial in minimizing oxidative stress in sporadic Alzheimer's disease and possible prevention of disease progression.

BACKGROUND AND OBJECTIVE: Serum level of digitalis-like factors or sodium pump inhibitors increase under numerous pathogenic circumstances. Diminution of sodium pump activity was reported to be secondary to beta-amyloid oligomers, though the mechanism involved remains inconclusive. Therefore, this study was conducted to evaluate the alteration in serum levels of endogenous ouabain and cerebrospinal fluid (CSF) sodium in an animal model of Alzheimer’s disease, induced by intracerebroventricular injection of streptozotocin (ICV-STZ). METHODS: In this empirical study, 48 male rats were randomly divided into six groups of saline and STZ. Alzheimer’s model was induced by ICV injection of STZ (3 mg/kg) on the first and third days. CSF samples were drawn from cisterna magna, and blood samples were collected from caudal vein. Thereafter, serum levels of ouabain and CSF sodium were evaluated 2, 7, and 14 days after STZ/saline injection in the test groups. Cresyl violet and Congo red stains were applied to study neuronal morphology and presence of amyloid plaques. FINDINGS: The mean serum levels of ouabain in the STZ groups were 0.2±0.05 ng/mL vs. 0.54±0.04 ng/mL on the second day, 0.3±0.02 ng/mL vs. 0.59±0.06 ng/mL on the seventh day, and 0.2±0.07 ng/mL vs. 0.65±0.08 ng/mL on the fourteenth day. These results indicated a significant increase of endogenous ouabain in the experimental groups compared to the saline groups (p