Different Parts Of Rat Brain Research Articles

Toxicity of multi-wall carbon nanotubes inhalation on the brain of rats.

This study was designed to investigate the brain toxicity following the respiratory contact with multi-wall carbon nanotubes (MWCNTs) in male Wistar rats. Rats were exposed to 5mg/m3 MWCNT aerosol in different sizes and purities for 5h/day, 5days/week for 2weeks in a whole-body exposure chamber. After 2-week exposure, mitochondrial isolation was performed from different parts of rat brain (hippocampus, frontal cortex, and cerebellum) and parameters of mitochondrial toxicity including mitochondrial succinate dehydrogenase (SDH) activity, generation of reactive oxygen species (ROS), mitochondrial membrane potential (MMP) collapse, mitochondrial swelling, and cytochrome c release, ATP level, mitochondrial GSH, and lipid peroxidation were evaluated. Our results demonstrated that MWCNTs with different characteristics, in size and purity, significantly (P < 0.05) decreased SDH activity, GSH, and ATP level, and increased mitochondrial ROS production, lipid peroxidation, mitochondrial swelling, MMP collapse, and cytochrome c release in the brain mitochondria. In conclusion, we suggested that MWCNTs with different characteristics, in size and purity, induce damage in varying degrees on the mitochondrial respiratory chain and increase mitochondrial ROS formation in different parts of rat brain (hippocampus, frontal cortex, and cerebellum).

Inhibition of Acetyl Cholinesterase Extracted from Five Parts of the Brain by 5,6 Dihydroxytryptamine

5,6 dihydroxytryptamine (DHT) is a neurogenic analogue of serotonin and physostigmine (eserine), both containing tertiary nitrogen group which is lipid soluble. The addition of 5,6 DHT to cholinesterase (ChE) extracted from whole and five different parts of rat brain namely: basal ganglia, cerebellum, frontal cortex, medulla oblongata, and pons in vitro was studied. The inhibition of ChE in the different parts of the brain was of the competitive type. The highest values of the enzyme‐inhibitor dissociation constant (Ki) were obtained with the extracts of medulla oblongata and pons. Those are the parts responsible for the vital centres. The inhibition of the extracts by DHT was reversible and the enzymes restored their whole activities by dialysis. The difference in the inhibition between the extracts of the parts was due to the difference in the gray and white matter content in these parts which was proved experimentally in this work. The inhibition was higher in the extracts obtained from the parts containing white matter than those containing gray matter. Erythrocyte and plasma ChEs were also inhibited by DHT. The inhibition of erythrocyte ChE was higher than plasma ChE and lower than the inhibition of the extracts of the brain parts. The inhibition of ChE by 5,6 DHT saves acetylcholine which helps in certain diseases like myasthenia gravis, Alzheimer's disease and Parkinsonism.Support or Funding InformationDepartment of Biochemistry, Medical Research Institute, Alexandria University,165 Horria Avenue Elhadarah, Alexandria, EGYPT

Regulation of Intermittent Hypoxia on Brain Dopamine in Amphetaminized Rats.

We investigated intermittent hypoxia (IH) on dopamine (DA) release in rat brain treated with or without amphetamine (AMPH). Rats were divided into four groups including normoxia, IH, AMPH, and AMPH + IH treatments. The cerebrospinal fluid (CSF) was collected and the DA levels were detected by high performance liquid chromatography (HPLC). The plasma prolactin (PRL) concentration was measured by radioimmunoassay (RIA). We found that IH reduced basal DA concentration in media prefrontal cortex (mPFC), but increased that in striatum, where DA level was also increased in rats treated with AMPH or AMPH + IH. Angiotensin II (Ang II) increased the DA release in mPFC and striatum and this effect was enhanced in AMPH + IH group. The stimulatory effect of IH on plasma PRL was attenuated in presence of AMPH. Tyrosine hydroxylase (TH) expression was decreased by IH, but increased by AMPH + IH in mPFC. IH or AMPH treatment decreased the expression of vesicular monoamine transporter-2 (VMAT-2) in rat brain. These data suggested that IH altered the DA release and changed the protein expression levels in different parts of rat brain treated with AMPH. IH may play a role in regulating DA metabolism in AMPH addiction.

Expression of vascular endothelial growth factor and microvessel density in different brain regions in aged rats

To observe the distribution of vascular endothelial growth factor (VEGF) and microvessel density (MVD) in different brain regions in aged rats and determine the role of VEGF and MVD in the aging process of the nervous system. We observed the expression of VEGF and MVD in different parts of rat brain in the 3- month group and 30-month group with immunohistochemical technique. Compared with the 3-month group, the 30-month group showed fewer VEGF-positive cells and MVD in the brain (P<0.01), and the number varied significantly in different brain regions (P<0.01). The motor cortex region contained more VEGF-positive cells and MVD than the hippocampus and cerebellum. VEGF-positive cells and MVD are decreased in every brain region of aged rats, and the motor cortex region contains more positive cells, suggesting exogenous VEGF may enhance the formation of microvessels and delay the aging of the nervous system.

Entry of oxime K027 into the different parts of rat brain: Comparison with obidoxime and oxime HI-6

Acetylcholinesterase reactivators (oximes) are highly hydrophilic compounds. This factor is considered to limit their distribution through the human body, especially into the central nervous system. However, some results contradict this hypothesis and confirm low concentrations of oximes inside the CNS. This study aims to verify oxime penetration through the blood–brain barrier, and into different brain regions.It has been confirmed that oximes can penetrate the BBB after therapeutic dose administration (0.73%, 0.69%, and 0.52% corresponding to obidoxime, HI-6, and new oxime K027). Although the whole brain level of K027 seems to be lower compared with other oximes we have to keep in mind that these numbers represent only a percentage of the concentration found in plasma. So, for more adequate comparison it is essential to have a look at the actual concentration of oximes in the wet brain tissue: 106.6±19.87ng/g (K027), 49.88±10.21ng/g (obidoxime) and 86.51±42.37ng/g (HI-6), where concentration of K027 was one order of magnitude higher than obidoxime and HI-6.In spite of the fact that the distribution of oximes into the CNS is minimal and concentrations differ from section to section, reasonable reactivation should still occur.

Effect of Carbamyl (Sevin) on the Activities of Acetyl Cholinesterase and Nitric Acid Synthase in Different Parts of Rat Brain

Carbamyl (sevin) is a wide spectrum carbamate insecticide. Its chemical structure is 1‐naphthalenyl methyl carbamate (C2 H11 NO2), m.w.201. The effect of sevin on both acetyl cholinesterase (AChE) and nitric oxide synthase (NOS) obtained from whole and five different parts of male albino rats namely: frontal cortex, basal ganglia, cerebellum, pons and medulla oblongata were studied. This work was carried out by two experiments: Exp. A: depending on the dose of intraperitoneal infusion of sevin, (0, 20, 30, 40 and 50 mg/kg BW) and decapitated after contstant time 10 min postinfusion, where signs of tremors, shivering, and craving for air. Exp. B:depending on the time course post infusion of a constant dose of sevin 40 mg/kg BW (dose causing 50% inhibition in vivo) The results indicated that sevin inhibited both AChE and NOS in the whole and different parts of the brain, and the degree of the inhibition differs from one part to another. AChE obtained from the pons and the cerebellum were highly inhibited than the other parts. Meanwhile NOS obtained from the pons and frontal cortex were highly inhibited than the other parts. The inhibition of both AChE and NOS was dose and time dependent. The parts which were the most affected by sevin are those responsible for the vital centers and coordination of movement. Medical Research Institute, Alexandria University, EGYPT

Inhibitory Effect of Acetylcholine on Monoamine Oxidase A and B Activity in Different Parts of Rat Brain

Acetylcholine (CAS 60-31-1, ACh), which is similar in its chemical structure to the carbamate aldicarb, was found to inhibit brain monoamine oxidase isoenzymes, namely MAO-A and B. The effect of ACh on both isoenzymes extracted from the whole brain of male albino rats and its different parts (frontal cortex, basal ganglia, cerebellum, pons and medulla oblongata) was studied. The results indicated that ACh inhibited MAO-A from the cerebellum and MAO-B from the basal ganglia more than MAO iso-enzymes from other brain parts. The inhibition was of the competitive type. It was also found that the enzyme inhibitor dissociation constants (Ki) and the affinity constants (Ki/Km) of MAO-A were higher than those of MAO-B.

Kindling epilepsy models with kainic acid in different parts of rat brain

Objective To discussion the methods of simpler production and better effect in the kainic acid induced epilepsy model. Methods By stereotactic operation,injection the kainic acid 1.0 μl to the insular, the amygdala and the lateral ventricle of the rats, observing the changes of the behavior, the EEG and the pathology and comparing the ignition characteristic in epileptic rats. Results The change of the behavior, the EEG and the pathology in epileptic rats confirmed that the rats of injection the kainic acid to insular can be successfully established experimental animal models. Compared to the traditional position (injection the kainic acid to amygdala and lateral ventricle) ,the insular ignite group primary seizure time is (59. 96 ±4. 36) min,static duration is(11. 90 ±0. 54) d,significantly faster than the amygdala group and the lateral ventricle group ( P ＜ 0. 05 ). Conclusion The insular has the seizure potency, the kainic acid injection the rat' s insular has the advantages in shortened test cycle and reduced the cost of experiments. Key words: Kainic acid; Epilepsy ; Insular; Amygdala

Comparative studies on chlorpyrifos and methyl parathion induced oxidative stress in different parts of rat brain: Attenuation by antioxidant vitamins

Organophosphate (OP) pesticides are among the most widely used synthetic chemicals for controlling a wide variety of pests. Chlorpyrifos ( o, o′-diethyl- o-3,5,6-trichloro-2-pyridyl phosphorothionate, CPF) is among the leading OP pesticides used extensively throughout the world including India while methyl parathion ( o, o-di methyl- o- p-nitrophenyl phosphorothioate, MPT) another OP compound, widely used as insecticide and acaricide to control many biting or sucking pests of agricultural crops. Present study was carried out to compare the chronic toxicity of CPF and MPT, their potential to generate oxidative stress and ameliorating effects of antioxidant vitamins in brain of rats. Results of the present study clearly demonstrated that the oral exposure of CPF or MPT, generated oxidative stress in different parts of rat brain consequently accumulating malondialdehyde (MDA) and 4-hydroxynonanal (4HNE), the two major end products of lipid peroxidation, in all the three brain regions i.e. fore-, mid- and hind-brain. The levels of hydrogen peroxide (H 2O 2) were also increased in all the three brain regions when compared with control. CPF and MPT exposure caused decrease in the levels of reduced glutathione (GSH) and increase in the levels of oxidized glutathione (GSSG) in all the three brain regions. The increase in the levels of MDA, 4HNE, H 2O 2 and GSSG was less pronounced when CPF or MPT was given to the rats fed with a mixture of vitamin A, E and C. The present findings clearly show that oral intake of a mixture of vitamin A, E and C protects the rats from MPT or CPF induced oxidative stress and suggest that this treatment alleviates the toxicity of these pesticides to a greater extent.

Chlorpyrifos induced alterations in the levels of hydrogen peroxide, nitrate and nitrite in rat brain and liver

Organophosphate pesticides are among the most widely used synthetic chemicals for controlling a wide variety of pests. Chlorpyrifos (CPF) is among the leading organophosphate (OP) pesticides used extensively throughout the world including India. Besides being potent anticholinesterase compounds, these OP pesticides are known to generate oxidative stress. Present study was carried out to see the level of reactive oxygen species (ROS), hydrogen peroxide (H 2O 2), nitrate (NO 3 −) and nitrite (NO 2 −) in different parts of rat brain and liver after giving different doses of CPF intramuscularly for 3 days or for 1 month. Results of the present study clearly revealed that levels of H 2O 2, NO 3 − and NO 2 − were increased significantly in all the three parts of rat brain i.e., fore-, mid- and hind-brain as well as in liver of rats given for 3 days or 1 month due to exposure of different doses of CPF. The study clearly demonstrated that CPF generated oxidative stress in all the three brain regions as well as liver of rats and the ROS were accumulated. Accumulation of ROS in all the regions of brain and other tissues may disturb the normal physiological functions aggravating the toxicity symptoms of CPF.

Dual effect of Alternariol on Acetylcholinestrase and Monoamine oxidase Extracted from Different Parts of Rat Brain

Alternariol is a metabolite product of different strains of alternaria tenuis. It's structure has a similarity to cannabinol derivatives .It has a chemical formula 3,4,5 trihydroxy 6‐ methyl dibenzox ‐pyrone.The effect of the alternariol on both acetylcholinestrase (AChE) and monoamineoxidase ( MAO) isozymes which were extracted from whole brain male albino rats and it's different five parts namely : frontal cortex, basal ganglia, cerebellum, pons , medulla oblongata was studied. Kinetic studies were done to determine the type of inhibition of AChE and MAO isozyme, and the enzyme ‐inhibitor dissociation constant (Ki) by alternariol.The results indicated that alternariol inhibited both AChE and MAO isozymes of the cortex and cerebellam more than the extracts of the other parts of the brain .These parts are responsible for perception , motor, sensony, psychic activities, coordination of movements and balance.The inhibition of these isozymes increased with increasing the amount of alternariol added to the assay mixture, i.e., the inhibition was dose dependent and of the competitive type. The values of Ki for alternariol ‐ AChE isozymesvaried from 12.0 to 15.0 mmol/L and for alternariol ‐ MAO isozymes varied from 28 to 30 mmol/L.The difference in the degree of inhibition of the extracts of these parts of the brain could be attributed to the slight difference in the structure ( arrangement of the amino acids) of these isozymes ( isozyme phenomenon) and to the distinct gene loci. The inhibition of AChE and MAO by alternariol may save ACh and biogenic amines which are ofgreat importance for the patients suffering from Alzheimer and dementia.

Separation of Renin-Like Activity from Acid Protease Activity in Different Parts of Rat Brain

Separation of Renin-Like Activity from Acid Protease Activity in Different Parts of Rat Brain

Dual Effect of Alternariol on Acetyl Cholinesterase and Monoamineoxidase Extracted from Different Parts of Rat Brain

Dual Effect of Alternariol on Acetyl Cholinesterase and Monoamineoxidase Extracted from Different Parts of Rat Brain

Effect of the Carbamate (Physostigmine) on the Activity of Nitric Oxide Synthase in Different Parts of Rat Brain (In Vivo Studies)

Effect of the Carbamate (Physostigmine) on the Activity of Nitric Oxide Synthase in Different Parts of Rat Brain (In Vivo Studies)

Effect of the Organophosphate [Curacron] on Activity of Acetylcholinesterase in Different Parts of Rat Brain [in Vivo Studies

Curacron profenofos is 0-[4-Bromo-2 chlorophenyl]-O-ethyl-S-propyl phosphorothioate. Its chemical formula is C11H15BrCIO3PS. It is a broad-spectrum organophosphorous insecticide for control of pests in cotton growing areas. Inhibition of acetyl and pseudocholinesterase by this compound results in signs and symptoms of toxicity signs and symptoms [cholinergic syndrome]: bradycardia, respiratory-circulatory arrest, vomiting and diarrhea in a variety of animals including man. In this work experiments were carried out in vivo to study its effect on the activity of AChE enzyme obtained from whole and five different parts of rat brain, namely basal ganglia, frontal cortex, medulla oblongata, pons, and cerebellum. This work was carried out by 2 experiments: Exp. A: Depending on the dose of intraperitoneal infusion of curacon. Exp. B: Depending on the time course post infusion of a constant dose of curacron 100 mg/kg BW [dose causing 50% inhibition] in vivo. The results showed that the inhibition occurred in all brain parts, but it was highly marked in the enzyme obtained from the cerebellum [the part responsible for balance and coordination of movements]. The results also indicated that the inhibition of AChE produced by i.p. injection with curacon was dose and time dependent.

Nuclear magnetic resonance for studying recognition processes between anandamide and cannabinoid receptors

The understanding of the molecular basis of cannabinoid activity has greatly improved since the discovery of CB1 and CB2 receptors. In this paper, the ligand binding processes between the endogenous cannabimimetic ligand, anandamide (AEA), and the cannabinoid receptors from different parts of rat brain were studied by nuclear magnetic resonance spectroscopy. The NMR approach is based on the comparison of selective (R 1 SE) and non-selective (R 1 NS) proton spin-lattice relaxation rates of the ligand in the presence and absence of macromolecular receptors, as well as R 1 NS and R 1 SE temperature dependency analysis. From these studies, the ligand–receptor binding strength was evaluated on the basis of the calculation of the “ affinity index”. The derivation of the “ affinity index” from chemical equilibrium kinetics for all systems allowed the comparison of the ability of anandamide to interact with cannabinoid receptors present in different brain sectors.

Effect of styrene oxide on levels of biogenic amines and activity of monoamine oxidase in different parts of rat brain.

Effect of styrene oxide on levels of biogenic amines and activity of monoamine oxidase in different parts of rat brain.

The effect of propranolol on rat brain catecholamine biosynthesis

The effect of propranolol on the levels of catecholamine in different parts of rat brain has been studied. The catecholamine contents of different regions were lowered by the drug. Dopamine Β-hydroxylase activity was also reduced, bothin vivo andin vitro. Propranolol is taken up by the brain tissue and the uptake is time-dependent. These results suggests that reduction in brain catecholamine levels and dopamine Β-hydroxylase activity may be one of the possible ways through which the drug manifests its clinical effects.

Microinjection of chlorpromazine in different parts of rat brain.

Abstract In lightly anaesthetized rats, a microinjection of chlorpromazine into the anterior part of the hypothalamus or into the third ventricle, but not into other parts of the brain, caused a long lasting rise in body temperature. The effect was also obtained in reserpine treated rats. Chlorpromazine sulphoxide which does not show the usual pharmacological effects of phenothiazine derivatives, was only slightly active when injected in high doses into the anterior part of the hypothalamus.