Medicine and Health Sciences Commons^™

Improved Social Interaction, Recognition And Working Memory With Cannabidiol Treatment In A Prenatal Infection (Poly I:C) Rat Model, Ashleigh L. Osborne, Nadia Solowij, Ilijana Babic, Xu-Feng Huang, Katrina Weston-Green

Illawarra Health and Medical Research Institute

Neuropsychiatric disorders such as schizophrenia are associated with cognitive impairment, including learning, memory and attention deficits. Antipsychotic drugs are limited in their efficacy to improve cognition; therefore, new therapeutic agents are required. Cannabidiol (CBD), the non-intoxicating component of cannabis, has anti-inflammatory, neuroprotective and antipsychotic-like properties; however, its ability to improve the cognitive deficits of schizophrenia remains unclear. Using a prenatal infection model, we examined the effect of chronic CBD treatment on cognition and social interaction. Time-mated pregnant Sprague-Dawley rats (n=16) were administered polyinosinic-polycytidilic acid (poly I:C) (POLY; 4 mg/kg) or saline (CONT) at gestation day 15. Male offspring …

Heme Consumption Reduces Hepatic Triglyceride And Fatty Acid Accumulation In A Rat Model Of Nafld Fed Westernized Diet, Soon Yew Tang, Irwin Kee M. Cheah, Pei Ern Ng, Aina Hoi, Andrew M. Jenner

Illawarra Health and Medical Research Institute

Studies have identified that serum-free hemoglobin subunits correlate positively with the severity of nonalcoholic fatty liver disease (NAFLD). However, the role of hemoglobin in the development of NAFLD remains unclear. In the present study, a rat model of NAFLD was developed, using a westernized diet high in saturated fat and refined sugar. Since a "westernized" diet is also high in red meat, we tested the effect of hemoglobin as a dietary source of heme in our model. Sprague-Dawley rats were fed ad libitum for 4 weeks either control diet (7% fat), westernized diet (WD, 18% fat + 1% cholesterol), hemoglobin …

Extracellular Chaperones Prevent Aβ42-Induced Toxicity In Rat Brains, Roberta Cascella, Simona Conti, Francesca Tatini, Elisa Evangelisti, Tania Scartabelli, Fiorella Casamenti, Mark R. Wilson, Fabrizio Chiti, Cristina Cecchi

Faculty of Science, Medicine and Health - Papers: part A

Alzheimer's disease (AD) is a progressive neurodegenerative disorder characterised by cognitive decline, formation of the extracellular amyloid β (Aβ42) plaques, neuronal and synapse loss, and activated microglia and astrocytes. Extracellular chaperones, which are known to inhibit amyloid fibril formation and promote clearance of misfolded aggregates, have recently been shown to reduce efficiently the toxicity of HypF-N misfolded oligomers to immortalised cell lines, by binding and clustering them into large species. However, the role of extracellular chaperones on Aβ oligomer toxicity remains unclear, with reports often appearing contradictory. In this study we microinjected into the hippocampus of rat brains Aβ42 oligomers …

Genomic Homeostasis Is Dysregulated In Favour Of Apoptosis In The Colonic Epithelium Of The Azoxymethane Treated Rat, Caroline A. Kerr, Barney M. Hines, Janet M. Shaw, Robert Dunne, Lauren M. Bragg, Julie Clarke, Trevor Lockett, Richard Head

Faculty of Science, Medicine and Health - Papers: part A

Background The acute response to genotoxic carcinogens in rats is an important model for researching cancer initiation events. In this report we define the normal rat colonic epithelium by describing transcriptional events along the anterior-posterior axis and then investigate the acute effects of azoxymethane (AOM) on gene expression, with a particular emphasis on pathways associated with the maintenance of genomic integrity in the proximal and distal compartments using whole genome expression microarrays. Results There are large transcriptional changes that occur in epithelial gene expression along the anterior-posterior axis of the normal healthy rat colon. AOM administration superimposes substantial changes on …

The Effects Of Insufflation Conditions On Rat Mesothelium, Andrew K. Davey, Jessica Hayward, Jean K. Marshall, Anthony E. Woods

Faculty of Science, Medicine and Health - Papers: part A

Aim. The aim of this investigation was to examine the alterations in the peritoneum after cold dry CO2, heated dry CO2, and humidified heated CO2 at pressures equivalent to intraperitoneal pressures used in human laparoscopy. Methods. Eighteen rats were divided into 4 treatment groups—group 1: untreated control; group 2: insufflation with cold dry CO2; group 3: insufflation with heated, dry CO2; group 4: insufflation with heated and humidified CO2. The abdomen was insufflated to 5 mm/Hg (flow rate 50 mL/min) for 2 h. Twelve hours later, tissue samples were collected for analysis by light microscopy (LM) and scanning electron microscopy …

Reducing Olanzapine-Induced Weight Gain Side-Effect By Using Betahistine: A Study In The Rat Model, Chao Deng, Jiamei Lian, Nagesh Brahmavar Pai, Xu-Feng Huang

Graduate School of Medicine - Papers (Archive)

Olanzapine is effective at treating multiple domains of schizophrenia symptoms. However, it induces serious metabolic side effects. Antipsychotic drug’s antagonistic affinity to histamine H1 receptors has been identified as a main contributor for weight gain/obesity side effects. This study therefore investigated whether a combined treatment of betahistine (a H1 receptor agonist and H3 receptor antagonist) could reduce the body weight/obesity induced by olanzapine. Female Sprague Dawley rats were treated orally with olanzapine (1 mg/kg, t.i.d.) and/or betahistine (2.67 mg/kg, t.i.d.), or vehicle for two weeks. Rats treated with olanzapine exhibited significant body weight gain and increased food intake. Co-treatment of …

Dietary Fish Oil Preserves Cardiac Function In The Hypertrophied Rat Heart, Peter L. Mclennan, Mahainda Y. Abeywardena, Julie A. Dallimore, Daniel Raederstorff

Graduate School of Medicine - Papers (Archive)

Regular fish or fish oil intake is associated with a low incidence of heart failure clinically, and fish oil-induced reduction in cardiac remodelling seen in hypertrophy models may contribute. We investigated whether improved cardiac energy efficiency in non-hypertrophied hearts translates into attenuation of cardiac dysfunction in hypertrophied hearts. Male Wistar rats (n 33) at 8 weeks of age were sham- operated or subjected to abdominal aortic stenosis to produce pressure-overload cardiac hypertrophy. Starting 3 weeks post-operatively to follow initiation of hypertrophy, rats were fed a diet containing 10% olive oil (control) or 5% fish oil (ROPUFA30 (17% EPA, 10% DHA)) …

Dietary Fish Oil Reduces Skeletal Muscle Oxygen Consumption, Provides Fatigue Resistance And Improves Contractile Recovery In The Rat In Vivo Hindlimb, Gregory E. Peoples, Peter L. Mclennan

Faculty of Health and Behavioural Sciences - Papers (Archive)

Dietary fish oil modulates skeletal muscle membrane fatty acid composition. Similar changes in heart membrane composition modulate myocardial oxygen consumption and enhance mechanical performance. The rat in vivo autologous perfused hindlimb was used to investigate the influence of membrane composition on skeletal muscle function. Male Wistar rats were fed either saturated fat (SF), n-6 PUFA (linoleic acid rich) or n-3 PUFA (fish oil) diets for 8 weeks. Hindlimb skeletal muscle perfused using the animal’s own blood was stimulated via the sciatic nerve (1 Hz, 6-12 V, 0·05 ms) to contract in repeated 10 min bouts. The n-3 PUFA diet markedly …

Effects Of Simvastatin And 6-Hydroxydopamine Lesion On Histaminergic H1 Receptor Binding In Rat Brains, C H. Hu, C Deng, Xu-Feng Huang, J Chen, Q Wang

Faculty of Health and Behavioural Sciences - Papers (Archive)

No abstract provided.

The Effect Of Vasoconstrictors On Oxygen Consumption In Resting And Contracting Skeletal Muscle Of The Autologous Pump-Perfused Rat Hindlimb, Andrew Hoy, Peter L. Mclennan, Gregory E. Peoples

Graduate School of Medicine - Papers (Archive)

No abstract provided.

Glutathione And Catalase Suppress Tgfß-Induced Cataract-Related Changes In Cultured Rat Lenses And Lens Epithelial Explants, Coral G. Chamberlain, Kylie J. Mansfield, Anna Cerra

Graduate School of Medicine - Papers (Archive)

Purpose: The damaging effects of oxidative stress and transforming growth factor-β (TGFβ)-induced transdifferentiation of lens epithelial cells have both been implicated independently in the etiology of cataract. The aim of this study was to investigate whether the presence of antioxidant systems in the lens influences the ability of lens epithelial cells to respond to TGFβ.

Methods: Whole lenses from young rats were cultured with or without TGFβ in the presence or absence of reduced glutathione (GSH). Lens epithelial explants from weanling rats were used to investigate the effects of GSH and catalase on TGFβ-induced cataract-related changes. Lenses were monitored for …

Primary Sensory Neuron Addition In The Adult Rat Trigeminal Ganglion: Evidence For Neural Crest Glio-Neuronal Precursor Maturation, Alfonso Lagares, Hong-Yun Li, Xin-Fu Zhou, Carlos Avendano

Illawarra Health and Medical Research Institute

It is debated whether primary sensory neurons of the dorsal root ganglia increase the number in adult animals and, if so, whether the increase is attributable to postnatal neurogenesis or maturation of dormant, postmitotic precursors. Similar studies are lacking in the trigeminal ganglion (TG). Here we demonstrate by stereological methods that the number of neurons in the TG of adult male rats nearly doubles between the third and eighth months of age. The increase is mainly attributable to the addition of small, B-type neurons, with a smaller contribution of large, A-neurons. We looked for possible proliferative or maturation mechanisms that …

Effects Of Dexamethasone On Posterior Capsule Opacification-Like Changes In A Rat Lens Explant Model, Kylie Mansfield, Anna Cerra, Coral Chamberlain

Faculty of Science, Medicine and Health - Papers: part A

Purpose: Many patients whose sight is initially restored by cataract surgery eventually suffer secondary loss of vision because of posterior capsule opacification (PCO; after-cataract), a condition in which lens epithelial cells left behind at surgery become aberrant and migrate into the light path. The aim of this study was to determine whether dexamethasone (DEX), an anti-inflammatory agent widely used before and after cataract surgery, influences the behavior of lens cells under conditions relevant to PCO development.

Methods: An established rat PCO model was used in which explanted epithelial cells attached to the lens capsule are exposed sequentially to TGFβ2 and …

Fgf-2 Counteracts Loss Of Tgfβ Affected Cells From Rat Lens Explants: Implications For Pco (After Cataract), Kylie Mansfield, Anna Cerra, Coral Chamberlain

Faculty of Science, Medicine and Health - Papers: part A

Purpose: While cataract surgery initially benefits most patients, many suffer secondary loss of vision because of posterior capsule opacification (PCO). Lens epithelial cells left behind at surgery become aberrant and migrate into the light path. TGF-beta (TGFβ) appears to play a key role in this process by inducing the cells to undergo an epithelial-mesenchymal transition. Paradoxically, it also typically induces them to undergo apoptotic death. The present study was undertaken to investigate the hypothesis that FGF plays a role in PCO formation by promoting the survival of abnormal cells with PCO-like characteristics.

Methods: Rat lens epithelial explants were cultured for …

The Reduced Effect Of Serotonin On Oxygen Consumption During Muscle Contraction In The Autoperfused Rat Hindlimb, Andrew Hoy, Gregory E. Peoples, Peter L. Mclennan

Faculty of Science, Medicine and Health - Papers: part A

Serotonin (5-HT) has been shown to reduce skeletal muscle oxygen consumption cY 02) during resting conditions in a variety of animal models. It is thought to act through redistribution of blood flow within skeletal muscle directing flow away from muscle tissue (nutritive bed) towards less metabolically active tissue, adipose and septum (non-nutritive bed) by selective vasoconstriction. The aim of this study was to test whether the effects of 5-HT (previously observed under resting conditions) are reproducible during the increased metabolic demand of muscle contraction.