Tehran University Medical Journal

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This cross-sectional descriptive study was undertaken to know the rate of intestinal parasites infestations in our school children population. A sum of 1155 fecal samples were analyzed from an equal number of children whose age were between 6-11 years old. The percentage of infestations were: Giardia lamblia (14.11%), hymenolepis nana (1.21%), ascaris lumbricoides (0.08%) and enterobius vermicularis (0.08%). We found no differences with regard to sex, age, father and mother levels of education, family size, body mass index (BMI) and the erythrocyte sedimentation rate (ER) between the stools positive and the stools negative cases. Nearly all cases of giardiasis (99.4%) were symptomatic. Eosinophilia was seen in (5.5%) of the infested children with giardiasis and in (0.5%) of the non-infested children, the difference was statistically non-significant (P=0.056). All cases of giardiasis (N=163) were treated with metronidazole 15 mg/kg/day in 3 divided doses for 7 days. Metronidazole was effective in (92.2%) of the treated children.

 

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The phenomenon of sleep is an active nervous and biologic rhythm, which is under influence of neurotransmitters of central nervous system. In this study, the influence of serotonergic system on sleeping time have been assessed by agonist-antagonist drugs using two methods of induction and non-induction behavioral and electrophysiology. The method used for measurement of total sleeing time was Angle method. For assessment of drugs impact on brain waves, after opening two holes in frontal and temporal regions, two non-polarized silvery electrodes were fixed in above regions and was connected to physiograph and computer by linkers for waves analysis. Injection intra-ventriculary is done by stereotax apparatus. Results indicate that diazepam (2.5 mg/kg) increases sleeping time in two stages of induction and non-induction (P<0.01). 5-HTP (15, 45 mg/kg) increases dose-dependence sleeping time. p-CPA (150, 300 mg/kg) shows biphasic influence on sleeping time. The 300 mg/kg dose of p-CPA reduces sleeping time while 150 mg/kg dose inverts sleeping time (P<0.05). Interferential affects of drugs with (5-HTP) 45 mg/kg and p-CPA (300 mg/kg) doses are similar to control groups. Injection of 5-HTP inverts p-CPA affect. Intra-ventriculary Injection of 5-HTP in 150 µg/kg and 300 µg/kg doses, decreases frequency of delta waves and significantly increases the frequencies of other waves but conversely, 500 µg/kg decreases it. Due to findings of this study, interferential affects of agonist-antagonist of 5-HTP, can not invert p-CPA affect. Supported by GABA affects, diazepam induces its inhibitory affect in per-synaptic and post-synaptic membrane through ascending reticular both systems and blocking stimulation of brain cortical and limbic system. Affects of two other drugs on sleeping time and brain waves are probably caused by increment of released serotonin in pre-synaptic neurons. Although their interferential affects with other neurotransmitter system should be considered as well.

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The phenomenon of sleep is an active nervous and biologic rhythm, which is under influence of neurotransmitters of central nervous system. In this study, the influence of serotonergic system on sleeping time have been assessed by agonist-antagonist drugs using two methods of induction and non-induction behavioral and electrophysiology. The method used for measurement of total sleeing time was Angle method. For assessment of drugs impact on brain waves, after opening two holes in frontal and temporal regions, two non-polarized silvery electrodes were fixed in above regions and was connected to physiograph and computer by linkers for waves analysis. Injection intra-ventriculary is done by stereotax apparatus. Results indicate that diazepam (2.5 mg/kg) increases sleeping time in two stages of induction and non-induction (P<0.01). 5-HTP (15, 45 mg/kg) increases dose-dependence sleeping time. p-CPA (150, 300 mg/kg) shows biphasic influence on sleeping time. The 300 mg/kg dose of p-CPA reduces sleeping time while 150 mg/kg dose inverts sleeping time (P<0.05). Interferential affects of drugs with (5-HTP) 45 mg/kg and p-CPA (300 mg/kg) doses are similar to control groups. Injection of 5-HTP inverts p-CPA affect. Intra-ventriculary Injection of 5-HTP in 150 µg/kg and 300 µg/kg doses, decreases frequency of delta waves and significantly increases the frequencies of other waves but conversely, 500 µg/kg decreases it. Due to findings of this study, interferential affects of agonist-antagonist of 5-HTP, can not invert p-CPA affect. Supported by GABA affects, diazepam induces its inhibitory affect in per-synaptic and post-synaptic membrane through ascending reticular both systems and blocking stimulation of brain cortical and limbic system. Affects of two other drugs on sleeping time and brain waves are probably caused by increment of released serotonin in pre-synaptic neurons. Although their interferential affects with other neurotransmitter system should be considered as well.

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Introduction: Inter-hospital transport constitutes one of the important parts of the emergency system in every country.

Materials and methods: To determine the outcome of requested CCU beds from the medical emergency headquarters in year 2000 by the hospitals affiliated to Tehran university of medical sciences, we have reviewed retrospectively 2688 clinical files of patients for whom a request for an empty CCU bed in other hospitals had been sent to the medical emergency headquarters. The main measure was the success rate of being admitted to CCU in other hospitals.

Results: On the whole 68.5 percent of requests were followed by a CCU admission to other hospitals. Using logistic regression method, variables including season of the year, shift diagnosis of the patient and the original hospital were shown to be related with the success rate. Conclusion: Increasing the number of available CCU beds and providing the centers with the necessary equipment is of high priority in hospitals located in city of Tehran.

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Background: One of the most important concerns in orthopedic medicine is the low back. Considering the importance of muscle function in preventing LBT by controlling too much load and stress applied on the spinal joints and ligaments.

Materials and Methods: The aim of this research was to determine the timing and level of activities of lumbopelvic muscles in response to postural perturbations caused by unexpected loading of the upper limbs in standing on three different supporting surfaces (neutral, positive slope, negative slope) in 20 healthy females 18 to 30 years old ( = 23.20 SD = 2.55 ). The electromyographic signals were recorded from the deltoid, gluteus maximus, internal oblique abdominis and lumbar paraspinal muscles of the dominant side of the body to evaluate the onset time, end time, level of muscle activity (RMS) and duration of different muscles in one task and one muscle in different tasks.

Results: The results showed that the agonists (posterior muscles) activated at first to compensate the flexor torque caused by loading and then the antagonists (anterior muscles) switched-on to compensate the reaction forces caused by agonist activities. With regards to continuous activity of internal oblique and its attachments via thoracalumbar fascia to the transverse processes of the lumbar vertebrae, it can be considered as one of the major stabilizer muscles of the trunk .

Conclusion: Finally the results indicated that supporting surface type didn’t have any effect on timing and scaling of muscle activities in different tasks suggesting that probably spinal and trunk priprioceptors are just responsible for triggering postural responses and they don’t have any role in determining timing and scaling.

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Background: Fumes generated during electric welding are one of air pollutants of working place in industrial companies, which can cause some clinical signs and diseases in worker, including mucosal irritation, changing of semen quality and cancer. Chronic exposure of workers with these fumes can cause reduce sperm motility and forward penetration and decrease in normal sperm count. Although a lot of researches were done in this field up to now, there is little information about histopathological effects of these fumes on germinal epithelium. The aim of this study was to identify structural changes of germinal epithelium in Rat as an experimental model after exposure to fumes of electric welding in exposure chamber.
Material and Methods: A total number of 60 Sprague Dawley Rats were chosen and divided into experimental (40) and control (20) groups. Each of groups was subdivided into 2, 4, 6 and 8-week subgroups. The number of Rat in each subgroup of experimental and control group was 10 and 5 respectively. Animals were housed in standard situation. After adaptation experimental group were exposed to fumes of electric welding (AMA 2000 electrode, 100 Ampere, 0.1 cm/s speed of electrode welding) for 2 hour/day and 5 day/week. The rate of air turn over in exposure chamber was fixed to 12-15/hour. The amount of O3, CO, CO2, NO + NO2 and particulate matter were measured by Galtec detectors and Cellulose acetate filter respectively. According to time table animals were killed and specimens from testis were taken and fixed in formaline buffer solution and processed routinely. Sections with 5-7 micrometer in thickness were stained by H-E, PAS, PNA and Alcian blue pH=2.5. The thickness of germinal epithelium was measured and data were analyzed by Kruskall Wallis test.
Results: The results of this study showed a few quantitative and qualitative changes in germinal epithelium. Vasodilatation of vessels in tunica albuginea and interstitial tissue, decreasing of eosinophilia in myoid cells, increase in size of spermatogonia especially dark type, disorganization of association between sertoli and spermatogenic cell lineage and spermatogenic arrests in spermatocyte I period. There were significant difference between experimental and control group for thickness of germinal epithelium (p<0.001).
Conclusion: It seems that although some adaptation response was appeared in experimental group, a lot of structural changes also appeared in germinal epithelium. The amount and severity of these changes were dependent to 3 factors include the amount of fumes, the variety of it and the duration of exposure.

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Background and Aim: Auditory and visual stimuli are the most important factors in communication. It seems during the brain maturation, decrease of visual inputs causes enhancement of somatosensory and auditory cortical responses. In this research latency and amplitude of auditory middle latency responses (AMLR) are studied in blinds and normally sighted subjects.

Materials and Methods: This descriptive-analytical study was performed on 40 congenitally blinds and 40 normally sighted subjects in the range of 14-20 years. All of cases had normal hearing sensitivity and acoustic reflexes without any middle ear disorders. The reason of this age range is the maturation of auditory middle latency responses. Sampling was randomized.

Results: There was significant difference between amplitude of Na, Pa & Nb waves and latency of Na while no significant difference between latency of Pa & Nb in blinds and normally sighted subjects.

Conclusion: Increase of amplitude and decrease of latency of AMLR in blind subjects were due to sensory compensation phenomenon, probably. It seems rate of processing and auditory perception in blinds is better than normally sighted subjects.

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Background and Aim: Pancytopenia is the reduction of all 3 series of blood cells e.g. Erythroids, leukocytes, and platelets. The causes of pancytopenia are diverse. Some are related to bone marrow failure caused by toxins (Bone Marrow with no cells or low cells). Bone marrow may be infiltrated by malignant and foreign cells or bone marrow fibrosis. Genetics factor and geographical disease could be also a factor in different distribution of pancytopenic etiology.

Materials and Methods: All patients with pancytopenia from 1373 to 1381 who were admitted to Army 501 hospital were evaluated. All hospital documents were evaluated. 188 patients had pancytopenia were diagnosed.

Results: 1. The commonest cause of pancytopenia was leukemia 2. Most cases of leukemia were acute myelogenous leukemia 3. Most leukemia cases were in 2nd decade of life in this group 4. Most of the patient had Anemia, weakness and fatigue

Conclusion: Pancytopenia should be regarded as a serious finding and evaluated thoroughly.

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Background and Aim: Spasticity is a velocity-dependent increase in tonic stretch reflexes (muscle tone) with exaggerated tendon jerks, resulting from hyperexcitability of the stretch reflex. The measurement of spasticity is necessary to determine the effect of treatments. The Modified Ashworth Scale is the most widely used method for assessing muscle spasticity in clinical practice and research. The purpose of this study was to investigate the interrater reliability of Modified Ashworth Scale in hemiplegic patients.

Materials and Methods: Thirty subjects (16 males, 14 females) with a mean age of 59.40 (SD =14.013) recruited. Shoulder adductor , elbow flexor , wrist dorsiflexor , hip adductor , knee extensor and ankle plantarflexor on the hemiplegic side were tested by two physiotherapists.

Results: In the upper limb, the interrater reliability for shoulder adductor and elbow flexor muscles was fair (0.372 and 0.369, respectively). The reliability for the wrist flexors was good (0.612). The difference in Kappa value for the proximal muscle (shoulder adductor 0.372) and the distal muscle (wrist flexor 0.612) was significant (²X=33.87, df=1, p<0.05). In the lower limb, the reliability for the hip adductor was fair (0.350), but for the knee extensor and ankle plantar flexor was moderate (0.518 and 0.542, respectively). The Kappa value for the proximal muscle (hip adductor: 0.350) and distal muscle (ankle plantar flexor0.542) had no significant difference (²X =1.35, df=1, p >0.05). The mean value for the upper limb (0.505) and the lower limb (0,.516) was not significantly different (²X=0.1407, df=1, p>0.05).

Conclusion: The interrater reliability of Modified Ashworth Scale was not good . The limb, upper or lower, had no significant effect on the reliability. In the upper limb, the reliability for the proximal and distal muscle was significantly different. However. The difference in the lower limb was not significant.When using the scale, one should consider it&aposs limitation.

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Background and Aim: With daily improvement of diagnostic modalities, accurate knowledge of anatomy and microanatomy is necessary and important, for better diagnosis of pathologic problems from normal variations. One of this very important anatomical sites is sella and suprasellar zones, where sensitive elements is noted. CT and MRI is very helpful in diagnosis and management of diseases as well as for differentiating of pathology from normal variation. A study was designed for evaluation of normal variation of this zones in normal men achieved.

Materials and Methods: 200 referral patients to CT center with headache and 200 referral patients to MRI center with headache which had normal imaging findings were chosen. We grouped the sella and suprasellar cistern on the basis of shapes, dimensions and normal variation.

Results: Different normal variations of soft tissues and bony elements in sella and suprasellar zones noted. Different shapes of sella turcica and suprasellar cistern and optic chiasma is noted.

Conclusion: Advanced imaging systems allows us to diagnosis of different formal sella and suprasellar cistern, so that accurate anatomic patterns were diagnosed for better evaluation of pathology and differentiation from normal variations. different CT patterns of sella and suprasellar regions are due to anatomic and technical variations. CT scaning with thin slices is necessary. Both CT and MRI are highly reliable in diagnosis of sella and suprasellar cistern lesions.

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Background: Cerebral palsy is the term used to describe a movement disorder though to be the result of nonprogressive brain damage. Due to damage to CNS, it is associated with articulation disorder and abnormal feeding reflex. Lack of oral function control and coordination following feeding reflex disorders. Articulation disorders are seen in most of the cerebral palsied patients.This research aimed to determine the relationship between feeding reflexes and articulation in cerebral palsy (spasticchildren).

Methods: This study was cross sectionally carried out on 52 children with cerebral palsy, 5 to 10 yrs old, in rehabilitation centers and private clinics. The information related to feeding reflexes was collected through direct observation of patient and evaluation of sound articulation through phonetic information test.

Results: Statistical analysis carried out by SPSS and chi-square and fisher exact tests. Abnomal chewing and tongue reflex are more prevalent than other feeding reflexes.The relationship between lip reflex and articulation of p/m/r/y/f/č and chewing reflex with articulation of/z/š/ is meaningful. The relationship between biting reflex with articulation of /z/j/l/š/ is meaningful. The relationship between tongue reflex and rooting reflex with articulation of sound is not meaningful.

Conclusion: With regard to the result of this research, it can be suggested that in children with cerebral palsy following feeding reflex disorders, abnormal posture during speech occurs that could have effect on articulation.

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Background: Some pregnant women are exposed to occupational noise, a risk factor for the development of the auditory system. The auditory system is one of the areas in embryonic development in which noise might induce aberrant development. Noise can change the gene expression pattern of an embryo and thereby modify the physiology of the auditory system. Therefore, noise can change the molecular structure of the developing ear. One of the critical molecules involved in development of auditory system is glycoconjugate. The aim of this study was to investigate the molecular changes of the developing spiral ganglion after exposure to industrial levels of noise.

Methods: A total of 42 pregnant mice were divided into control and experimental groups. Each group was further divided into three subgroups. The three experimental subgroups were exposed to daily noise with an intensity of 100 db for 2.5 hours until sacrifice (for the first group to be sacrificed) or day seven of postnatal life (for the other two groups). The mice offspring were sacrificed at the first, seventh and 14^th days of postnatal life. The inner ears were prepared histologically. The specimens were stained with the lectins wheat germ antigen (WGA), peanut agglutinin (PNA), Dolichos biflorus agglutinin (DBA) and BSAI-B4.

Results: The results indicated that, although there were no histological changes at the light-microscopic level in the ear development, statistical analysis showed that there was a significant decrease in the uptake of the BSA1-B4 lectin by neurons of spiral ganglion in 14th day of postnatal life in the experimental group compared to  that of the control group (p<0.05).

Conclusions: After noise exposure, in spite of normal neuronal structure, these cells were modified at the molecular level, especially in glycoconjugate expression, influencing the normal physiology of neurons and causing auditory disorders.

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Normal 0 false false false EN-US X-NONE AR-SA MicrosoftInternetExplorer4 Background: Hairy cell leukemia (HCL) is a rare B-cell neoplasm that comprise approximately 2% of all lymphoid leukemias. Over the past 20 years splenectomy was the only effective therapy but with the advent of purine analogues such as cladribine, splenectomy has been limited to certain situations. After cladribine therapy most patients achieve complete and durable remission. The aim of this study was to compare effectiveness of splenectomy and cladribine in Iranian patients with HCL and also to evaluate the clinical and laboratory features of patients at diagnosis.
Methods: 50 patients with the diagnosis of HCL enrolled to our study. The male to female ratio was 3:1, and the median age at diagnosis was 50 years. After diagnosis  20(40%) and 12(24%) of patients had splenectomy and cladribine therapy respectively. The reminder of patients were treated with both splenectomy and cladribine.
Results: The most common clinical findings were splenomegaly (98%) and fatigue (80%) respectively. Leucopenia and anemia was present in 96% and 80% patients in order. 88.6% and 55.5% of patients achieved complete remission after cladribine therapy and splenectomy respectively. After cladribine therapy and splenectomy relapse occurred in 10% and 74% of the patients.
Conclusions: Our finding are comparable with previous studies and show that Cladribine induces complete and durable remission in most hairy cell leukemia patients and should be considered as first line therapy. Splenectomy should be performed in certain cases such as spleen rupture.

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Background: Numerous evidences indicate that various environmental stresses during pregnancy affect physiological behavior of the offspring. This experimental study was designed to investigate the effect of noise stress during prenatal period of rats on spatial learning and memory and plasma corticostrone level in postnatal life.
Methods: Three groups of pregnant rats were given daily noise stress with durations of two and/ or four hours in last week of pregnancy period. The fourth group was left unstressed. The male offspring from the unstressed and different stressed groups were assigned as controls and stressed groups. The animals were introduced to a spatial task in Morris water maze 4 trials/day for five consecutive days. The probe test was performed on the 5^th day of the experiment. The delay in findings and the distance passed to locate the target platform were assessed as the spatial learning.
Results: Our results showed that prenatal exposure to noise stress for two and/ or four hours a day, leads to impaired acquisition of spatial learning in the postnatal animals. The plasma level of corticostrone in the two stressed groups of rats markedly matched with their behavioral function. Prenatal exposure to 1- hour noise stress revealed no effects on the offsprings' behavior and plasma corticostrone level.
Conclusion: Based on our study results, it seems that applied range of stress which is executed through the noise stress could increase the plasma corticostrone level and could decrease spatial learning and memory of adult male offspring.

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Background: Polycystic ovary syndrome (PCOS) is the most common cause of anovulatory infertility. Metformin which is effectively used for the treatment of anovulatory PCOS improves pregnancy rate and endometrial receptivity and reduces the risk of miscarriage. The aim of this study was to evaluate the effects of metformin on the endometrium, the number of fetuses and hormonal levels of PCOS rats. Methods: Forty female adult Sprague-Dawley rats were assigned randomly into four equal groups. Group I: control rats, group II: rats receiving metformin (150 mg/kg/day), group III: Estradiol Valerate-induced PCOS rats (4 mg/rat) and group IV: induced PCOS rats receiving metformin. Body weight and serum levels of glucose, LH, FSH, testosterone, progesterone and estradiol were measured. Following mating, each group was divided into two subgroups and the rats were sacrificed on the 5th and 15th day of gestation to evaluate endometrial reaction to implantation and fetus count, respectively. Results: Hormone assay showed a significant increase in testosterone, estradiol, LH, FSH and blood glucose levels in group III compared to the controls (P≤0.01) and a significant decrease in blood glucose in group IV versus group III (P≤0.01). Progesterone concentration had no significant differences between groups III and the controls. Weight was higher in group III than group I but it had no decrease after metformin administration. No significant differences were detected regarding implantation rate and number of fetuses in all rats. Conclusion: Metformin has significant effects on pregnancy rate and the hormonal and blood glucose levels of Estradiol Valerate-induced PCOS rats.

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Background: Diabetes mellitus affects numerous intracellular metabolic processes, which are reflected by changes in the concentration of some plasma constituents. Particularly, the disease may indirectly undermine some functions of the nervous system including learning and memory through altering oxidative stress status. On the other hand, probiotics can enhance the antioxidant capacity. This study was designed to evaluate the effects of probiotics on spatial memory, maze learning and indices of oxidative stress in diabetic rats.
Methods: In this experimental study, 40 male Wistar rats were randomly allocated to 4 groups (n=10 for each): Control (CO), Control probiotic (CP), Control diabetic (DC), and Diabetic probiotic (DP). The probiotic supplement, including Lactobacillus acidophilus, Lactobacillus fermentum, Bifidobacterium lactis (334 mg of each with a CFU of ~1010), was administered through drinking water every 12 hours for 8 weeks. Using morris water maze (MWM), spatial learning and memory were evaluated. Serum insulin and oxidative stress indices, including superoxide dismutase (SOD) and 8-hydroxy-2'-deoxyguanosine (8-OHdG), were measured by standard laboratory kits.
Results: Oral administration of probiotics improved impairment of spatial learning (P=0.008) and consolidated memory (P=0.01) in the rats. Moreover, probiotic treatment increased serum insulin (P<0.0001) and serum superoxide dismutase activity (P=0.007) while it decreased their blood glucose (P=0.006) and 8-OHdG (P<0.0001).
Conclusion: Probiotic supplementation reversed the serum concentrations of insulin and glucose along with an increase in antioxidant capacity in diabetic rats. It also improved spatial learning and memory in the animals. Relevancy of the metabolic changes and behavioral functions need to be further studied.

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Background: Respiratory distress syndrome is developmental immaturity of lungs, that is caused by lack of surfactant. Lack of surfactant lead to wide atelectasis and arterial hypoxemia which is a life-threatening lung disorder. The aim of this study was to compare the function of cochlear in infant who suffer respiratory distress syndrome with normal infants by transient evoked otoacoustic emission (TEOAE) test. Methods: This descriptive- analytic cross sectional study was carried out on 21 respiratory distress syndrome (RDS) infants (42 ear) that consists of 11 male and 10 female, 21 normal infants (42 ear) that consists of 10 male and 11 female in Mirza Koochakkhan Hospital, Tehran University of Medical Sciences, Tehran, Iran, which all of them were 3 to 6 month year old, to collect informations about the health of infants we used the files in hospital and to assess the cochlear function we used computerized recording by TEOAE instrument. Statistical analysis carried out by SPSS software version 17 and Chi-square test. Results: The results of TEOAE test demonstrated that in normal group there is no statistical differences between ears and gender, also there was no statistical differences between ears in respiratory distress syndrome group but there was statistical differences between gender in this group. The frequency of pass result (show normal function of outer hair cell in cochlea) was greater in male than female in male the frequency of pass result was 17 ear (77.3%) but in female was 8 ear (40%). In TEOAE test results there was statistical differences between two groups of study. The frequency of pass result in normal group was 34 ear (81%) and in respiratory distress syndrome group was 25 ear (59%) which was significantly more in normal group than in respiratory distress syndrome infants (P= 0.032). Conclusion: According to results, it seems that the respiratory distress syndrome could affects the cochlear and the function of outer hair cell in it so in infants who suffer respiratory distress syndrome we should use the test battery of hearing.

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Background: Environmental signals have an essential role in the maturation of neural circuits during critical period of brain development. It has been shown that, change in visual signals during critical period of brain development changes structure and function of glutamate receptors in the visual cortex. After processing in visual cortex, part of visual signals goes to the hippocampus and makes memories. The aim of this study was evaluating effects of visual deprivation during critical period of brain development on AMPA receptor subunits expression in rats’ hippocampus. Methods: This experimental study was done in Physiology Research Center, Kashan University of Medical Sciences at winter 2014 on male Wistar rats. Animals were divided to 2 groups (n= 36 for each) were kept in standard 12 hours light/12 hours dark condition (light reared, LR) or in complete darkness (dark reared, DR) from birth to the end of the experiments. Using reverse transcription polymerase chain reaction (RT-PCR) and Western blotting techniques respectively, expression of mRNA and protein of GluR1 and GluR2 subunits was evaluated in rats’ hippocampus at ages 2, 4 and 6 weeks in both groups. After quantification of the expressions, the data were compared by two way analysis of variance. Results: The relative expression of GluR1 subunit decreased about 24% (P=0.004) in the hippocampus of 6 WLR rats in comparison to 2 WLR ones. The relative expression of the other AMPA receptor subunit, GluR2, also increased about 190% in the hippocampus of the 6WLR animals when compared to the 2 WLR rats (P< 0.0001). Dark rearing increased the relative expression of both subunits of AMPA receptors, GluR1 and GluR2, about 20 percent (P= 0.01) in the hippocampus of 6 WDR rats in comparison to 2 WLR animals. Conclusion: Dark rearing of rats during critical period of brain development changes the relative expression and also arrangement of both AMPA receptor subunits, GluR1 and GluR2 in the hippocampus, age dependently.

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