Evan Rats Research Articles

Evaluation of antidiabetic activities of linseed (linum usitatissimum l.) Sprout extracts in adult Streptozotocin-induced (a-stz) long-evan rats

The study investigates the anti-diabetic properties of linsseed (Linum usitatissimum L.) sprout extracts in adult streptozotocin (STZ)-induced Long-Evan rats, addressing the limitations of existing treatment strategies in Bangladesh. The diabetic rats were administered orally with 400 mg/kg body weight of methanolic extracts of linseed sprout with a lab diet and glibenclamide as a positive control. Blood sugar levels were measured before, after, and after STZ injection in Long- Evan rats. The lipid profiles and liver function tests were performed. Administration of extracts of linseed sprouts and a standard anti-diabetic drug reduced the glucose level from 9.1 mmol/l to 6.0 mmol/l and 10.5 mmol/l to 6.6 mmol/l , respectively. The study also showed a healthy level of liver function tests and lipid profiles. The in vivo analysis of the potential antidiabetic activity of linseed sprouts in the STZ-induced diabetic mouse model might be used to treat and manage diabetes. Bangladesh J. Bot. 53(3): 503-510, 2024 (September)

Memory protective effect of Phyllanthus emblica against scopolamine induced spatial memory loss in male Long Evan Rats tested by Radial Arm Maze

Background: Dementia is the commonest problem of middle aged and elderly subjects due to age related changes and oxidative stress. Many traditional herbal agents including Emblica Officinalis (Phyllantus Emblica) demonstrated its benefit against memory loss. Objective: To investigate the protective effect of Ethanolic extract of Phyllantus Emblica (EEPE) or Emblica Officinalis in scopolamine induced memory impaired male Long Evan rats. Methods: This animal behavioral study was carried out on total 18 male long Evan rats weighing 300-400gm. According to treatment they were divided into NS (control) group (n=6, normal saline 5ml/kg) Sco(n=6; Scopolamine 2mg/kg) and PE(n=6; EEPE 400mg/kg+ Scopolamine 2mg/kg).This experiment was conducted for total 33 days. After 7 days acclimatization NS group and PE rats were treated with normal saline and EEPE respectively for consecutive 26 days. Scopolamine was given to sco group and PE group from day 22 to 26 (5 days during acquisition phase. Spatial memory (working and reference memory error) was assessed by 8 arm radial arm maze (RAM). Statistical analysis was done by ANOVA followed by Bonferroni’s post hoc test. Result: Working memory error (WME) as well as reference memory error (RME) was found significantly higher in scopolamine treated rats compared to normal memory as well as PE pretreated rats whereas no significant difference was found in WME and RME between normal memory rats and PE pre- treated rats. Conclusion: Phyllanthus Emblica can prevent memory impairment in scopolamine induced memory loss in Long Evan rats. J Bangladesh Soc Physiol 2022;17(2): 101-110

Exposure to dithiocarbamate fungicide Ziram results in hepatic and renal toxicity in Long Evan rats

Ziram is a dimethyldithiocarbamate fungicide that is complexed to the metal zinc. The focus of this study is to examine the effects of dimethyldithiocarbamate exposure on metal homeostasis, glutathione levels, and the physiological parameters of the kidney and liver in Long-Evan rats. Our results indicate significant accumulation of copper or zinc, and changes in total GSH or GSH/GSSG ratio in the liver and kidneys of animals treated with Ziram only. Histopathological examination of liver and kidney sections indicate the presence of infiltrates in the liver of animals treated with Ziram only, whereas protein aggregates, sloughing of cells and increased KIM-1 positive cells, an indicator of tubule deterioration, are seen in the kidneys of animals treated with Ziram and sodium-dimethyldithiocarbamate, the salt form of the dimethyldithiocarbmate backbone. These findings suggest that the overall toxicological effect of Ziram is mediated by an intrinsic property rather than to dimethyldithiocarbamate backbone or metal moiety.

Liposomal Drug Delivery of Blumea lacera Leaf Extract: In-Vivo Hepatoprotective Effects.

Background: Blumea lacera (B. lacera) is a herbaceous plant commonly found in south-east Asia. It shows significant therapeutic activities against various diseases. The objectives of this study were to evaluate hepatoprotective effects of Blumea lacera leaf extract and also to investigate the comparative effectiveness between a liposomal preparation and a suspension of B. lacera leaf extract against carbon tetrachloride (CCl4)-induced liver damage. Methods: B. lacera leaf extract was characterized using a GC-MS method. A liposomal preparation of B. lacera leaf extract was developed using an ethanol injection method and characterized using dynamic light scattering (DLS) and electronic microscopic systems. The hepatoprotective effects of B. lacera leaf extracts and its liposomal preparation were investigated using CCl4-induced liver damage in Long Evan rats. Results: GC-MS data showed the presence of different components (e.g., phytol) in the B. lacera leaf extract. DLS and microscopic data showed that a liposomal preparation of B. lacera leaf extracts was in the nano size range. In vivo study results showed that liposomal preparation and a suspension of B. lacera leaf extract normalized liver biochemical parameters, enzymes and oxidative stress markers which were elevated due to CCl4 administration. However, a liposomal formulation of B. lacera leaf extract showed significantly better hepatoprotective effects compared to a suspension of leaf extract. In addition, histopathological evaluation showed that B. lacera leaf extract and its liposomal preparation treatments decreased the extent of CCl4-induced liver inflammations. Conclusion: Results demonstrated that B. lacera leaf extract was effective against CCl4-induced liver injury possibly due to the presence of components such as phytol. A liposomal preparation exhibited significantly better activity compared to a B. lacera suspension, probably due to improved bioavailability and stability of the leaf extract.

Chronic traumatic stress impairs memory in mice: Potential roles of acetylcholine, neuroinflammation and corticotropin releasing factor expression in the hippocampus

Chronic stress in humans can result in multiple adverse psychiatric and neurobiological outcomes, including memory deficits. These adverse outcomes can be more severe if each episode of stress is very traumatic. When compared to acute or short term stress relatively little is known about the effects of chronic traumatic stress on memory and molecular changes in hippocampus, a brain area involved in memory processing. Here we studied the effects of chronic traumatic stress in mice by exposing them to adult Long Evan rats for 28 consecutive days and subsequently analyzing behavioral outcomes and the changes in the hippocampus. Results show that stressed mice developed memory deficits when assayed with radial arm maze tasks. However, chronic traumatic stress did not induce anxiety, locomotor hyperactivity or anhedonia. In the hippocampus of stressed mice interleukin-1β protein expression was increased along with decreased corticotropin releasing hormone (CRH) gene expression. Furthermore, there was a reduction in acetylcholine levels in the hippocampus of stressed mice. There were no changes in brain derived neurotrophic factor (BDNF) or nerve growth factor (NGF) levels in the hippocampus of stressed mice. Gene expression of immediate early genes (Zif268, Arc, C-Fos) as well as glucocorticoid and mineralocorticoid receptors were also not affected by chronic stress. These data demonstrate that chronic traumatic stress followed by a recovery period might lead to development of resilience resulting in the development of selected, most vulnerable behavioral alterations and molecular changes in the hippocampus.

Effects of Dietary Isoflavones, Age, and Stroke on Estrogen Pathway Activation in Male Rats

The effects of stroke can cause long lasting impairment on not only one's physical health but their quality of life and everyday function. Dietary modifications provide a potential solution to aid in neuroprotection and allow enhanced functional recovery post‐stroke. Previous investigation tested this, and found the addition of dietary soy compounds does show significantly improved functional recovery through behavioral tests in our rat models. Further studies aimed to identify specific effects on gene expression on the dietary inclusion of isoflavones alone, using Daidzein and Genistein, known neuroprotective estrogenic receptor activators. We not only examined the effect of isoflavone content on altered gene expression, but also age as another potential mediating factor either promoting or inhibiting anti‐inflammatory and neuroprotective pathways. In doing so, both adult and aged male Hooded Long Evan rats were separated into distinct dietary protein groups containing either Sodium Caseinate (CAS), or Sodium Caseinate with the isoflavones daidzein and genistein (CAS+ISO) two weeks before a permanent unilateral middle cerebral artery occlusion (MCAO). Tissue samples were collected from the injured hemisphere on Day +3 (n=6) and Day +0 (n=4; received no MCAO). Data were collected via a qPCR array after RNA extraction and cDNA synthesis, following the manufacturer's protocol guidelines (Qiagen). Expression of mRNA was compared between treatment groups based on age, isoflavone content, and stroke. Changes in mRNA expression greater than 2‐fold were considered significant. Detailed results will be presented on the poster.Support or Funding InformationNIH NCCAM (1R15AT006593; JLC) and DuPont Nutrition and Health

Effects of genetic strain on stress‐induced weight and body fat loss in rats: application to air pollution research (703.3)

Exposure to some air pollutants is suspected of contributing to obesity. Hazelton chambers are commonly used in air pollution studies but we found unexpected reductions in body weight and body fat of rats housed in Hazelton chambers under control conditions. We suspect that stress from housing in Hazelton chambers could compromise data from a study on air pollutant‐induced obesity. Male Long Evan (LE), Sprague Dawley (SD), Brown Norway (BN) and Fisher (F344) rats were housed individually in Hazelton chambers for 6 h, 1 day/wk for 3 wks. Using a Bruker NMR system, % body fat was measured before and after exposure and compared to cage controls. Housing in the chambers led to strain‐dependent decreases in %body weight and body fat. Weight loss was greatest in LE and SD (4.4+0.3% and 4.0+0.2%, respectively, on wk 1). BN and F344 were less affected (3.2+0.2% and 3.8+0.3%, respectively, on wk 1). Body fat was reduced by 0.6% in BN and LE rats at 5 d after exposure in the Hazelton Chambers. Overall, housing in Hazelton chambers appears to be a stressor leading to significant weight loss and lipolysis that is strain‐dependent. BN and LE rats may not be the best model to use to study possible links of air pollutants to obesity. This abstract does not necessarily reflect US EPA policy.

Abstract B47: Neural cells labeling with intracerebral ferumoxytol iron oxide nanoparticles in a rat model.

Abstract Purpose: To investigate uptake of ferumoxytol iron oxide nanoparticles into rat neural cells for a clinically applicable magnetic resonance (MR) imaging technique. Materials and Methods: Long Evan rats were injected with intracerebral ferumoxytol (360 μg) iron oxide nanoparticles into the right hemisphere. A needle track in the left hemisphere was used as a sham control. Animals underwent T2-weighted fast spin-echo MRI sequences at 12T 48 h after nanoparticle inoculation. Immediately after MRI, single brain cell suspensions were produced from the right and left hemispheres, and neurospheres were stained for iron using Prussian blue histochemstry. Results: The ferumoxytol-injected right hemisphere showed decreased T2 signal compared to the sham injected left hemisphere. Positive iron staining was found in neural cells from the right cerebral hemisphere, although <5% of total cell number, while no positive iron staining cells were found in the left hemisphere. The decreasing T2 signal does not correlate the percentage of neural cells labeled with ferumoxytol iron oxide nanoparticles, indicating most of the nanoparticles were not cell-associated. The phenotypes of ferumoxytol-labeled neural cells will be characterized by immunohistochemistry for neural markers. No neural cell in vitro labeling was detected using ferumoxytol in combination with protamine sulfate and heparin. Conclusion: Iron oxide loading of neural cells in the brain parenchyma can be achieved with the clinically approved agent ferumoxytol. Iron labeling may be utilized to monitor neuro-inflammation and brain tumors after chemotherapy for non-invasive MRI. Citation Format: Yingjen Jeffrey Wu, Leslie L. Muldoon, Edward A. Neuwelt. Neural cells labeling with intracerebral ferumoxytol iron oxide nanoparticles in a rat model. [abstract]. In: Proceedings of the AACR Special Conference on Tumor Immunology: Multidisciplinary Science Driving Basic and Clinical Advances; Dec 2-5, 2012; Miami, FL. Philadelphia (PA): AACR; Cancer Res 2013;73(1 Suppl):Abstract nr B47.

Forskolin induced increase in spontaneous activity of auditory brainstem neurons is comparable to acoustic stimulus evoked responses

Contemporary proposals for the pathophysiology of tinnitus due to cochlear damage underscore increased spontaneous activity of auditory brainstem neurons. One of the several consequences of the cochlear injury is the activation of the ERK pathway, suppression of phosphodiestase E activity, and putatively setting a long-term increase in intracellular levels of cyclic AMP at central auditory neurons. Local application of forskolin also increases intracellular cyclic AMP and spontaneous neural activity. We measured the effects of locally applied forskolin on spontaneous firing rate of isolated neurons in the peri-olivary region of the superior olive complex in anesthetized adult Long Evan rats. Forskolin induced increase in spontaneous neural activity was comparable to supra-threshold tone evoke neural responses. These results are viewed in context of hyperexcitability as a correlate of tinnitus.

The anti-ulcerogenic effect of an alkaloidal fraction from Mikania cordata on diclofenac sodium-induced gastrointestinal lesions in rats.

A decoction of Mikania cordata (Compositae) is commonly used for the treatment of gastric ulcer in the Rajbari district of Bangladesh. We have evaluated the anti-ulcerogenic effect of the alkaloidal fraction from the whole plant of M. cordata on diclofenac sodium-induced gastrointestinal lesion in rats. Long Evan's rats were divided into five groups. The control group was kept undisturbed. The vehicle group received vehicle after a 48-h fast. The diclofenac group received diclofenac sodium suspension (80 mg kg(-1)) after a 48-h fast. The diclofenac-ranitidine group (anti-ulcer drug used as a standard) received 35 mg kg(-1) ranitidine hydrochloride suspension 1 h after diclofenac sodium administration, after a 48-h fast. The diclofenac-extract group received alkaloidal fraction (50 mg kg(-1)) 1 h after diclofenac administration, after a 48-h fast. The biochemical, morphological and histological changes were studied. The data showed that the pH values of the stomach and duodenum were increased significantly (P < 0.001) in the alkaloidal-administered group compared with the control group (3.09 +/- 0.0429 vs 2.07 +/- 0.0339 and 6.79 +/- 0.1162 vs 6.19 +/- 0.1273, respectively). There were significant changes (P < 0.001) detected in the morphological study. The ulcer index of the stomach (0.268 +/- 0.0346) and of the duodenum (0.050 +/- 0.0129) in the alkaloidal-administered group were significantly lower than the diclofenac-only administered group (0.691 +/- 0.0184 and 0.0933 +/- 0.0138, respectively). According to the grading of tissue damage in the histological study, there were less or no lesions on the gastrointestinal mucosa of the alkaloidal-administered group compared with the diclofenac-only group (0 vs 5, respectively). When the results of the alkaloid extract group where compared with the ranitidine hydrochloride group a similar or more potent effect was observed with the alkaloidal extract group. The results of this study revealed that the bioactive principles of M. cordata have anti-ulcerogenic effects. The results validate the traditional use of this plant for the treatment of gastric ulcer in Bangladesh.

Roles of corticosterone in formalin-induced conditioned place aversion in rats

Glucocorticoid hormones have been shown to contribute to many cognitive functions, such as depressions, learning and memory, and abnormal glucocorticoid secretion results in functional changes in prefrontal cortex and amygdala. In the present study, we used the conditioned place aversion (CPA) paradigm to investigate the role of corticosterone (CORT) in the negative affective component of chemical somatic pain induced by intraplantar injection of formalin into male adult Long–Evan rats. Five percent of formalin produced acute biphasic nociceptive behaviors, including flinching and licking of hindpaw, and CPA. Intraplantar formalin induced CPA was abolished by bilateral adrenalectomy and the impairment of CPA can be restored by the CORT treatment. However, the adrenalectomy failed to affect the formalin-produced acute nociceptive behaviors. Therefore, data from the present study suggest that CORT secretion by the adrenal cortex may play a role in chemical somatic noxious stimuli-induced avoidance learning and aversive memory, but not sensory discrimination of noxious stimulation.

Toxicological Studies of Two Compounds Isolated from Loranthus globosus Roxb

The sub-acute toxicities of two compounds 3,4-dimethoxycinnamyl alcohol (1) and 3,4,5-trimethoxycinnamyl alcohol (2) isolated from the plant Loranthus globosus Roxb were studied on long Evan's rats. The studies included the gross general observation such as changes in body weight, haematological profiles [total count of Red Blood Cells (RBC) and White Blood Cells (WBC), differential count of WBC, platelet count and Haemoglobin (Hb)%], biochemical parameters of blood [Serum Glutamate Oxaloacetate Transaminase (SGOT), Serum Glutamate Pyruvate Transaminase (SGPT), Serum Alkaline Phosphatase (SALP), urea and creatinine) and histopathology of the liver, kidney, heart and lung of both control and experimental groups of rats. The changes in haematological and biochemical parameters were statistically not significant after the administration of compounds 1 and 2 in a dose of 300 microg/rat/day for consecutive 14 days. No abnormality was found in the histopathology of the liver, kidney, heart and lung in the experimental groups of rats following same dose when compared with control group. This preliminary study suggests that the isolated compounds may be used safely for clinical trial.

Development of multiorgan pathology in the wpk rat model of polycystic kidney disease.

Rodent models of polycystic kidney disease (PKD) have provided valuable insight into the cellular changes associated with cystogenesis in humans. The present study characterizes the morphology of renal and extrarenal pathology of autosomal recessive PKD induced by the wpk gene in Wistar rats. In wpk(-/-) rats, proximal tubule and collecting duct cysts develop in utero and eventually consume the kidney. Increased apoptosis, mitosis, and extracellular tenascin deposition parallel cyst development. Extrarenal pathology occurs in the immune system (thymic and splenic hypoplasia) and central nervous system (CNS; hypoplasia to agenesis of the corpus callosum with severe hydrocephalus). Severity of hydrocephalus varied inversely with size of the corpus callosum. In wpk(-/-) rats, the corpus callosum exhibits relatively few axons that cross the midline. This CNS pathology is similar to that described in three human renal cystic syndromes: orofaciodigital, genitopatellar, and cerebrorenal-digital syndromes. Collecting duct and ventricular ependymal cilia appear morphologically normal. To determine if rodent background strain and the presence of modifier genes affect severity of the disease, we crossed the Wistar-wpk rat with Brown Norway (BN) and Long Evan (LE) rats and found the degree of renal and cerebral pathology was diminished as evidenced by lower kidney weight as a percent of body weight and serum urea nitrogen concentration in cystic rats on LE or BN strains as well as less prominent cranial enlargement. Crosses with BN rats allowed us to localize the wpk gene on chromosome 5 very close to the D5Rat73 marker. The wpk gene lies within a chromosomal region known to harbor a PKD modifier locus. In summary, the types of renal and cerebral pathology seen in the Wistar wpk rat are a unique combination seen only in this rodent model.

Comparison of the Relative Inhibition of Acetylcholinesterase and Neuropathy Target Esterase in Rats and Hens Given Cholinesterase Inhibitors

Comparison of the Relative Inhibition of Acetylcholinesterase and Neuropathy Target Esterase in Rats and Hens Given Cholinesterase Inhibitors. Ehrich, M., Jortner, B. S., and Padilla, S. (1995). Fundam. Appl. Toxicol.24, 94-101.Inhibition of neuropathy target esterase (NTE, neurotoxic esterase) and acetylcholinesterase (AChE) activities was compared in brain and spinal cords of adult White Leghorn hens and adult male Long Evan rats 4-48 hr after administration of tri-ortho-tolyl phosphate (TOTP po. 50-500 mg/kg to hens: 300-1000 mg/kg to rats), phenyl saligenin phosphate (PSP im 0.1-2.5 mg/kg to hens; 5-24 mg/kg to rats), mipafox (3-30 mg/kg ip to hens and rats), diisopropyl phosphorofluoridate (DFP sc, 0.25-1.0 mg/kg to hens; 1-3 mg/kg to rats), dichlorvos (5-60 mg/kg ip to hens; 5-30 mg/kg to rats), malathion (75-300 mg/kg po to hens; 600-2000 mg/kg to rats), and carbaryl (300-560 mg/kg ip to hens; 30-170 mg/kg to rats). Inhibitions of NTE and AChE were dose-related after administration of all compounds to both species. Hens and rats given TOTP, PSP, mipafox, and DFP demonstrated delayed neuropathy 3 weeks later, with spinal cord lesions and clinical signs more notable in hens. Ratios of NTE/AChE inhibition in hen spinal cord, averaged over the doses used, were 2.6 after TOTP. 5.2 after PSP, 1.3 after mipafox, and 0.9 after DFP, which contrast with 0.53 after dichlorvos, 1.0 after malathion, and 0.46 after carbaryl. Rat NTE/AChE inhibition ratios were 0.9 after TOTP, 2.6 after PSP, 1.0 after mipafox, 0.62 after DFP, 1.3 after dichlorvos, 2.2 after malathion, and 1.1 after carbaryl. The lower NTE, AChE ratios in rats given dosages of the four organophosphorus compounds that caused delayed neuropathy interferred with survival, an effect that was not a problem in hens. This observation, along with the absence of overt and specific clinical signs and the restricted presence of neuropathological lesions in rats, suggests that the hen remains the animal of choice for testing for organophosphorus-induced delayed neuropathy.

Immune system of the spontaneously hypertensive rat I. Sympathetic innervation

Extensive bidirectional interactions are believed to exist between the sympathetic nervous system and the immune system. The spontaneously hypertensive rat (SHR) is known to possess both increased sympathetic nervous system activity with increased tissue catecholamine levels in several peripheral organs and a moderate T lymphocyte immune deficiency. We examined the development of innervation in both primary (thymus) and secondary (spleen) organs of the immune system of the SHR compared to immunocompetent Wistar-Kyoto (WKY), Fisher 344 (F-344), and Long Evan (LE) rats from birth through 24 weeks. Using glyoxylic acid-induced histofluorescence to visualize monoaminergic nerve fibers, coded specimens were examined and morphologically evaluated for the extent and distribution of innervation. The innervation of the SHR thymus was significantly increased at 2 and 12 weeks of age over the other strains. Unlike the control strains, splenic innervation in SHR was delayed until 2 weeks of age when it suddenly became exuberant. At 12 weeks, the innervation of the SHR spleen was increased over all control strains. By 24 weeks the innervation had regressed to a level comparable to the levels of the other rat strains in these tissues. During the suckling period, the size (weight) of the WKY spleen was larger and the level of innervation was decreased compared to the other strains. These strain-related differences in the development of sympathetic innervation of thymus and spleen likely reflect the complex, bidirectional interplay between the nervous and the immune systems. However, increased innervation of immune organs occurs at critical time points (2 weeks, beginning of, and 12 weeks maturation of immune function) in SHR, suggesting that sympathetic innervation may be contributing to the immune deficiency of the SHR.

Neuroleptic-induced vacuous chewing movements as an animal model of tardive dyskinesia: a study in three rat strains

Vacuous chewing movements (VCMs) in three different rat strains developed at considerably different rates after 19 weeks of continual haloperidol treatment at an average daily dose of 1.5 mg/kg. Sprague Dawley (SD) rats displayed relatively high rates of VCMs with low variability, compared to Wistar (W) and Long Evan (LE) rats. Atropine decreased but did not abolish VCMs in two of the three strains (LE greater than SD). After haloperidol withdrawal, VCMs remitted gradually in all strains, but least rapidly in the SD rats. In a separate group of SD rats. VCMs were rated weekly from the start of haloperidol treatment and showed considerable interindividual variability. Even after 24 weeks of continuous haloperidol, 12 out of 32 treated rats showed no VCMs at all, while 13 out of 32 had intense movements, analogous to the clinical situation in which only some patients treated with neuroleptics develop tardive dyskinesia. These results indicate that there are individual and strain differences in the development of VCMs, and suggest that there may also be genetically determined differences in the development of tardive dyskinesia.

Effects of preservation on the osteoinductive capacity of demineralized bone powder allografts.

Demineralized bone powder (DBP) has repeatedly been shown to serve as an osteoinductive material. The aim of this study was to investigate the effects of different methods of storage of DBP on its osteoinductive property. Forty-five Long Evan rats were used in this study. Twenty rats were used as donors; the diaphyses of their femoral bones were used for the preparation of DBP. The DBP was divided into four portions that were either lyophilized or frozen at -70 degrees C, -4 degrees C, or kept at room temperature (25 degrees C). All samples were stored under the specified condition for six months. At the time of implantation, fresh DBP was prepared and used as a control. Twenty-five rats were divided equally into five groups. Each group received an implant of either one of the differently preserved and stored samples of DBP or fresh DBP. The animals were killed 60 days following implantation. The implants were excised and processed to obtain 5 micron thick decalcified sections and 3 micron thick undecalcified sections. Semicomputerized histomorphometry was used for the quantification of the newly-formed bone in each implant. Newly-formed bone was detected in all experimental and control groups and there were no statistically significant differences between the various groups. It was concluded that DBP retains its osteoinductivity after lyophilization or preservation at -70 degrees C, -4 degrees C, and 25 degrees C for a period of up to six months, and that the different methods of preservation did not significantly affect the amount of the induced newly-formed bone.(ABSTRACT TRUNCATED AT 250 WORDS)

Effects of lithium on water intake and renal concentrating ability in rats with vasopressin-deficient diabetes insipidus (Brattleboro strain)

Male and female Long Evan rats and Brattleboro rats with ADH-deficient diabetes insipidus were treated with lithium administered in the diet for 12 weeks. The plasma lithium level was about 1 mmol/l in all groups. Lithium caused polydipsia and polyuria and lowering of renal concentrating ability in normal rats. In rats with ADH deficiency lithium tended to increase water intake, but did not influence spontaneous urine osmolality or maximal urine osmolality during water deprivation. The results indicate that the renal concentrating defect caused by lithium in rats can be explained by ADH-blockade as the only mechanism. However, there is circumstantial evidence that lithium in addition may stimulate thirst mechanisms by an ADH-independent action.

Effect of &lt;i&gt;Spirulina platensis&lt;/i&gt; on Lipid Profile of Long Evans Rats

To study the Effect of Spirulina platensis on lipid profile of Long Evan rats, an experiment was conducted by feeding the rats with diets supplemented with Spirulina platensis dry powder. Five different types of diets were included in the feeding. Group A containing high fat and high sugar considered as control-01. Group B with high fat, high sugar and 0.5% Spirulina. Group C with high fat, high sugar and 2.5% Spirulina. These three groups were included in Diet-1. Group D with laboratory diets considered as control-02 and Group E i.e., laboratory diet with Spirulina 150mg/kg/body weight. These two groups were included in Diet-2. This study describes the useful effect of Spirulina powder after administration in high fat and high sugar diet and in normal laboratory diet. Spirulina platensis powder showed an effective result in the lipid profile of Long Evan rats. Total cholesterol (TC) serum lipid significantly reduced in Group B than that of 2.5% of Spirulina powder in Group C rats. 0.5% and 2.5% Spirulina powder had the same effect in dropping low density lipoprotein (LDL) in both B and C Groups of rats. Conversely 2.5% Spirulina powder was found more effective in increasing high density lipoprotein (HDL) in Group C (50.54%) rats than the group B (24.18%) rats. On the other hand, the dose 150mg/kg b.w Spirulina powder mixed in laboratory diet showed an effective result in decreasing total cholesterol (TC) and low density lipoprotein (LDL) 19.21% and 46.06%, respectively. The findings clearly indicated that 150mg/kg b.w Spirulina powder had positive effect to increase the value of high density lipoprotein (HDL) in Group E (24.98%) rats compare to control group D rats. There were no significant differences in diet-1 groups' TC, TG and LDL-C of the groups of A (control- 01), B and C (p&lt;0.05), although they varies statistically for HDL among these groups (p&gt;0.05). On the other hand in diet-2 groups' TG, LDL and HDL of E groups of rats were significantly varies than control-2 groups of rats D ( p&gt;0.05), although TC was not significant statistically (p&lt;0.05). Keywords: High fat diet; Body weight (b.w); Hypercholesterolemia; Hypolipidaemic; Spirulina platensis. DOI: 10.3329/bjsir.v45i3.6533Bangladesh J. Sci. Ind. Res. 45(3), 249-254, 2010

Hepatoprotective and Antibacterial Activity of Ursolic Acid Extracted from &lt;i&gt;Hedyotis corymbos&lt;/i&gt;a L.

Hedyotis corymbosa (L) (Khetpapra in Bengali), a weedy herb of Rubiaceae family is used as a traditional medicine in Bangladesh for the treatment of Jaundice and other liver disorders. In the present study, hepatoprotective and anti-bacterial activity of ethanolic extract of the herb and ursolic acid isolated from it were investigated against paracetamol induced hepatotoxicity in Long Evan's rats and also against some selective gram positive and ten gram negative bacteria. The ethanolic extract of the plant showed significant hepatoprotective effect as evident by decreased serum enzyme levels, SGPT, SGOT, SAKP and SBIL, and also by normal histological architecture of the liver when compared to the paracetamol treated group. Moreover, ethanolic extract, n-hexane fraction and ursolic acid showed maximum activity of 18, 19, 21 mm against Sarcina lutea, Klebsiella pneumonia and Staphylococcus aureus respectively when compared with standard kanamycin disc (30 μgm/disc). These results thus support Hedyotis corymbosa and ursolic acid as hepatoprotective and antibacterial agent. Key Words: Hedyotis corymbosa; Ursolic acid; Hepatoprotective activity; Antibacterial activity. DOI: 10.3329/bjsir.v45i1.5174 Bangladesh J. Sci. Ind. Res. 45(1), 27-34, 2010