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Frieder B, Grimm VE. Prenatal Monosodium Glutamate (MSG) Treatment Given Through the Mother's Diet Causes Behavioral Deficits in Rat Offspring. Int J Neurosci 2009; 23:117-26. [PMID: 6541212 DOI: 10.3109/00207458408985353] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
The present study reports various developmental and behavioral changes in the offspring of rat dams that received monosodium glutamate (MSG) in the drinking water all through the second and third trimesters of pregnancy. Three main effects were observed in the MSG exposed offspring: (1) juvenile obesity; (2) reduced general activity levels; (3) a specific type of learning disability in discrimination learning involving choice between simultaneously present positive and negative stimuli.
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2
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Gonzalez FF, Miller SP. Does perinatal asphyxia impair cognitive function without cerebral palsy? Arch Dis Child Fetal Neonatal Ed 2006; 91:F454-9. [PMID: 17056843 PMCID: PMC2672766 DOI: 10.1136/adc.2005.092445] [Citation(s) in RCA: 100] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Some studies on neurodevelopmental outcomes after neonatal encephalopathy have suggested that cognitive deficits do not occur in the absence of cerebral palsy. It is increasingly apparent that childhood survivors of overt neonatal encephalopathy may have cognitive impairments, even in the absence of functional motor deficits. The risk of cognitive deficits is related to the severity of neonatal encephalopathy and the pattern of brain injury on neuroimaging, particularly the watershed pattern of injury. A better understanding of the risk factors for cognitive abnormalities after neonatal encephalopathy will ultimately lead to interventions to prevent these deficits. Identifying the full spectrum of neurodevelopmental outcomes after neonatal encephalopathy will also allow care givers to identify children requiring early intervention to maximise their potential for independent function throughout development.
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Affiliation(s)
- F F Gonzalez
- Department of Pediatrics, University of California, San Francisco, California, USA
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Hoeger H, Engidawork E, Stolzlechner D, Bubna-Littitz H, Lubec B. Long-term effect of moderate and profound hypothermia on morphology, neurological, cognitive and behavioural functions in a rat model of perinatal asphyxia. Amino Acids 2006; 31:385-96. [PMID: 16944046 DOI: 10.1007/s00726-006-0393-z] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2005] [Accepted: 01/26/2006] [Indexed: 11/29/2022]
Abstract
BACKGROUND Perinatal asphyxia is a frequent cause of neurological handicap with no known therapy. However, hypothermic therapy has recently attracted attention owing to its neuroprotective property in brain of immature organisms. OBJECTIVES Hypothermia appears to be promising in reversing the immediate effect of perinatal asphyxia, but data on long-term neuroprotection is still lacking. We therefore intended to test the long-term effect of moderate and profound hypothermia on brain morphology and functions using a well established rat model of perinatal asphyxia. METHODS Rat pups delivered by caesarean section were placed into a water bath, still in patent membranes, at 37 degrees C and variable hypothermic conditions to induce asphyxia and thereafter given to surrogate mothers. Examinations were performed at the age of three months, consisting of a battery of motor, behavioural, cognition and reflex tests including rota-rod, Morris water maze, multiple T-maze, elevated plus maze and open field studies. Morphological alterations were evaluated by Nissl staining of brain areas known to be hypoxia sensitive. Neurotransmission system markers, including tyrosine hydroxylase, vesicular monoamine transporter, vesicular acetylcholine transporter and excitatory amino acid carrier1 were analyzed by immunohistochemistry. RESULTS Survival increased with hypothermia. The Nissl stain revealed neuronal loss in hippocampus and hypothalamus of normothermic asphyxiated group (20/37) compared to controls (0/37), but no neuroprotective patterns emerged from hypothermia. An overall inconsistent protection of the neural systems was noted by variable periods of hypothermia. Motor function was significantly impaired in 20/37 as compared to 0/37. In the Morris water maze and multiple T-maze, results were comparable between the groups. In the elevated plus maze, time spent in the closed arm was reduced and in the open field, vertical behaviour was altered in the 20/37 group with horizontal motor behaviour being unaffected. Hypothermia reversed all abnormalities seen in 20/37, with short-term moderate and profound hypothermia being superior to long-term hypothermia. CONCLUSION Hypothermia not only significantly increased survival, but also resulted in unimpaired motor as well as improved cognitive functions. Those findings are in contrast to altered brain morphology. As neuronal loss was present in various brain regions, we conclude that deficits may be compensated in the maturing animal. Intrahypoxic hypothermia was able to protect the rat from the devastating effect of perinatal asphyxia not in morphological, but in functional terms.
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Affiliation(s)
- H Hoeger
- Institute for Animal Breeding, Medical University of Vienna, Vienna, Austria
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4
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Strata F, Coq JO, Byl N, Merzenich MM. Effects of sensorimotor restriction and anoxia on gait and motor cortex organization: implications for a rodent model of cerebral palsy. Neuroscience 2005; 129:141-56. [PMID: 15489037 DOI: 10.1016/j.neuroscience.2004.07.024] [Citation(s) in RCA: 55] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 07/08/2004] [Indexed: 10/26/2022]
Abstract
Chronic or acute perinatal asphyxia (PA) has been correlated with the subsequent development of cerebral palsy (CP), a developmental neurological disorder characterized by spasticity and motor abnormalities often associated with cognitive deficits. Despite the prevalence of CP, an animal model that mimics the lifetime hypertonic motor deficits is still not available. In the present study, the consequences of PA on motor behavior, gait and organization of the primary motor cortex were examined in rats, and compared with the behavioral and neurological consequences of early postnatal movement-restriction with or without oxygen deprivation. Rats subjected to PA had mild increases in muscular tone accompanied by subtle differences in walking patterns, paralleled by significantly altered but relatively modest disorganization of their primary motor cortices. Movement-restricted rats, suffering PA or not, had reduced body growth rate, markedly increased muscular tone at rest and with active flexion and extension around movement-restricted joints that resulted in abnormal walking patterns and in a profoundly distorted representation of the hind limbs in the primary motor cortex. Within the sensorimotor-restricted groups, non-anoxic rats presented the most abnormal pattern and the greatest cortical representational degradation. This outcome further supports the argument that PA per se may represent a substrate for subtle altered motor behaviors, and that PA alone is sufficient to alter the organization of the primary motor cortex. At the same time, they also show that early experience-dependent movements play a crucial role in shaping normal behavioral motor abilities, and can make a powerful contribution to the genesis of aberrant movement abilities.
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Affiliation(s)
- F Strata
- Keck Center for Integrative Neuroscience, Coleman Laboratory and Department of Otolaryngology-Head and Neck Surgery, University of California at San Francisco, 513 Parnassus Avenue HSE-832, San Francisco, CA 94143-0732, USA.
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Weitzdoerfer R, Pollak A, Lubec B. Perinatal asphyxia in the rat has lifelong effects on morphology, cognitive functions, and behavior. Semin Perinatol 2004; 28:249-56. [PMID: 15565784 DOI: 10.1053/j.semperi.2004.08.001] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Perinatal asphyxia (PA) is a major determinant of neurological morbidity and mortality in the neonatal period. Many studies have been investigating neurological deficits following PA, including seizures, cerebral palsy, mental retardation, as well as psychiatric deficits. Most research performed so far has been focusing on acute or subacute sequelae and has uncovered a variety of morphological, neurochemical, behavioral, and cognitive changes following PA. However, information on long-term sequelae of animals that underwent a period of PA is scanty. Perinatally asphyxiated rats at the end of their life span present with immunohistochemical and synaptic changes as well as changes in brain protein expression. Furthermore, deficits in cognitive function tested in the Morris water maze and changes in social behavior were described. In this review, we are summarizing and discussing reported effects of global PA on morphology, cognitive functions, and behavior in rats at the end of their life span.
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Van de Berg WDJ, Kwaijtaal M, de Louw AJA, Lissone NPA, Schmitz C, Faull RLM, Blokland A, Blanco CE, Steinbusch HWM. Impact of perinatal asphyxia on the GABAergic and locomotor system. Neuroscience 2003; 117:83-96. [PMID: 12605895 DOI: 10.1016/s0306-4522(02)00787-x] [Citation(s) in RCA: 50] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Perinatal asphyxia can cause neuronal loss and depletion of neurotransmitters within the striatum. The striatum plays an important role in motor control, sensorimotor integration and learning. In the present study we investigated whether perinatal asphyxia leads to motor deficits related to striatal damage, and in particular to the loss of GABAergic neurons. Perinatal asphyxia was induced in time-pregnant Wistar rats on the day of delivery by placing the uterus horns, containing the pups, in a 37 degrees C water bath for 20 min. Three motor performance tasks (open field, grip test and walking pattern) were performed at 3 and 6 weeks of age. Antibodies against calbindin and parvalbumin were used to stain GABAergic striatal projection neurons and interneurons, respectively. The motor tests revealed subtle effects of perinatal asphyxia, i.e. small decrease in motor activity. Analysis of the walking pattern revealed an increase in stride width at 6 weeks of age after perinatal asphyxia. Furthermore, a substantial loss of calbindin-immunoreactive (-22%) and parvalbumin-immunoreactive (-43%) cells was found in the striatum following perinatal asphyxia at two months of age. GABA(A) receptor autoradiography revealed no changes in GABA binding activity within the striatum, globus pallidus or substantia nigra. We conclude that perinatal asphyxia resulted in a loss of GABAergic projection neurons and interneurons in the striatum without alteration of GABA(A) receptor affinity. Despite a considerable loss of striatal neurons, only minor deficits in motor performance were found after perinatal asphyxia.
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Affiliation(s)
- W D J Van de Berg
- Department of Pediatrics, Research Institute Growth and Development (GROW), University of Maastricht, The Netherlands.
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7
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Nyakas C, Markel E, Schuurman T, Luiten PGM. Impaired Learning and Abnormal Open-field Behaviours of Rats After Early Postnatal Anoxia and the Beneficial Effect of the Calcium Antagonist Nimodipine. Eur J Neurosci 2002; 3:168-174. [PMID: 12106215 DOI: 10.1111/j.1460-9568.1991.tb00077.x] [Citation(s) in RCA: 41] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
Perinatal anoxia/hypoxia is considered a serious risk factor for normal brain development. Anoxia induced by repeated asphyxia at 2 and 4 days after birth resulted in a transient hyperactivity in the small open-field, and a behavioural depression in adult open-field activity of male Wistar rats. The same treatment impaired adult learning behaviour in pole-jumping conditioned avoidance and appetitively motivated hole-board test situations. The calcium entry blocker nimodipine (in doses of 3 and 10 mg/kg) prevented the anoxia-induced changes in orientation motility in the open-field tests and almost fully antagonized the learning deficit in the hole-board test. The behavioural deficit seen during acquisition of the pole-jumping conditioned avoidance response was ameliorated to a lesser degree. The results indicate that the maintenance of calcium homeostasis during the early postnatal phase of brain development is crucial to prevent anoxia-induced behavioural abnormalities.
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Affiliation(s)
- C. Nyakas
- Central Research Division, University of Postgraduate Medicine, Budapest, Hungary
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8
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Abstract
Obstetric complications involving anoxia or prolonged hypoxia are suspected to increase the risk for such mental disorders as schizophrenia and attention deficit-hyperactivity disorder. In previous studies, we reported evidence of enhanced nucleus accumbens (NAcc) dopamine (DA) function in adult rats subjected to intrauterine anoxia during cesarean (C) section birth. In the present study, we used voltammetry and monoamine-sensitive electrodes to investigate the possibility that this functional hyperactivity of the meso-NAcc system is attributable to a loss of inhibitory control from the medial prefrontal cortex (PFC). We monitored the DA responses to repeated once-daily stress in the right or left PFC of adult male rats born vaginally (VAG) or by C-section, either with (C + 15) or without (C + 0) an additional 15 min of intrauterine anoxia. In C + 15 animals, we observed a pronounced and persistent blunting of stress-induced DA release in the right PFC but not in the left; with repeated testing, a similar pattern of dampened right PFC DA stress responses emerged in C + 0 animals. In addition, C + 15 animals were spontaneously more active than VAG and C + 0 animals and displayed an increase in PFC DA transporter density that was also lateralized to the right hemisphere. There was no evidence, however, that PFC D(1) and D(2) receptor levels differed between birth groups or hemisphere. These findings suggest a mechanism by which perinatal complications involving anoxia might contribute to the etiology of mental disorders that have been linked to disturbances in central DA transmission and lateralized PFC dysfunction.
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9
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Hoeger H, Engelmann M, Bernert G, Seidl R, Bubna-Littitz H, Mosgoeller W, Lubec B, Lubec G. Long term neurological and behavioral effects of graded perinatal asphyxia in the rat. Life Sci 2000; 66:947-62. [PMID: 10714895 DOI: 10.1016/s0024-3205(99)00678-5] [Citation(s) in RCA: 52] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Perinatal hypoxic-ischemic states can cause irreversible damage to the brain, ranging from minimal brain dysfunction to death. Only few studies have been reported describing neurological, cognitive and behavioral deficits following perinatal asphyxia. We therefore decided to study long term effects of perinatal asphyxia in a well-documented animal model resembling the clinical situation. Caeserean section in rats was performed and the pups, still in the uterus horns, were placed into a water bath at 37 degrees C for periods of 5-20 min; pups were then given to surrogate mothers and examined at three month of age. Examinations consisted of a battery of motor and reflex tests, Morris water maze, multiple T-maze, elevated plus maze and open field studies. No abnormalities were found in rats even with long periods of perinatal asphyxia by neurological examination, in the open field and in mazes. Interestingly, in the elevated plus maze rats with long lasting exposure to hypoxia (15 and 20 min of asphyxia) showed reduced anxiety-related behavior. This finding may be relevant for the explanation of anxiety related disorders in adulthood with a tentative history in the perinatal period.
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Affiliation(s)
- H Hoeger
- University of Vienna, Dpt. of Pediatrics, Austria
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Dell'Anna E, Iuvone L, Calzolari S, Geloso MC. Effect of acetyl-L-carnitine on hyperactivity and spatial memory deficits of rats exposed to neonatal anoxia. Neurosci Lett 1997; 223:201-5. [PMID: 9080467 DOI: 10.1016/s0304-3940(97)13411-5] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
The effect of acetyl-L-carnitine (ALC) on behavioral deficits following neonatal anoxia (N2 100% for 25 min at 30 h after birth) was studied in the rat. Transient hyperactivity at P20-P45 postnatal days and permanent spatial memory deficits were shown by anoxic rats. A chronic ALC treatment (50 mg/kg per die injected intraperitoneally from P2, after anoxia, to P60) significantly reduced the transient increase in sniffing, rearing and locomotory activity of anoxic rats, but, mostly, ameliorated the spatial memory performances in a maze at P30-P40 and in a water maze at P50-P60. No behavioral changes were seen in ALC-treated animals that received sham-exposure at birth. On the basis of these results, the use of ALC for the treatment of perinatal asphyctic insults in children is suggested.
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Affiliation(s)
- E Dell'Anna
- Department of Experimental and Clinical Pathology and Medicine, University of Udine, Italy.
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11
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Abstract
Hypoxia threatens brain function during the entire life-span starting from early fetal age up to senescence. This review compares the short-term, long-term and life-spanning effects of fetal chronic hypoxia and neonatal anoxia on several behavioural paradigms including novelty-induced spontaneous and learning behaviours. Furthermore, it reveals that perinatal hypoxia is an additional threat to neurodegeneration and decline of cognitive and other behaviours during the aging process. Prenatal hypoxia evokes a temporary delay of ingrowth of cholinergic and serotonergic fibres into the hippocampus and neocortex, and causes an enhanced neurodegeneration of 5-HT-ir axons during aging. Neonatal anoxia suppresses hippocampal ChAT activity and up-regulates muscarinic receptor sites for 3H-QNB and 3H-pirenzepine binding in the hippocampus in the early postnatal age. The altered development of axonal arborization and pre- and postsynaptic cholinergic functions may be an important underlying mechanism to explain the behavioural deficits. As far as the cellular mechanisms of perinatal hypoxia is concerned, our primary aim was to study the putative importance of Ca2+ homeostasis of developing neurons by means of pharmacological interventions and by measuring the development of immunoexpression of Ca(2+)-binding proteins. We assessed that nimodipine, an L-type calcium channel blocker, prevented or attenuated the adverse behavioural and neurochemical effects of perinatal hypoxias, while it enhanced the early postnatal development of ir-Ca(2+)-binding proteins. The results are discussed in the context of different related research areas on brain development and hypoxia and ischaemia.
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Affiliation(s)
- C Nyakas
- Department of Animal Physiology, University of Groningen, Haren, The Netherlands
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12
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Buwalda B, Nyakas C, Vosselman HJ, Luiten PG. Effects of early postnatal anoxia on adult learning and emotion in rats. Behav Brain Res 1995; 67:85-90. [PMID: 7748505 DOI: 10.1016/0166-4328(94)00108-r] [Citation(s) in RCA: 45] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
Cognitive functioning, behavioural attention and anxiety were studied in adult male Wistar rats after early postnatal anoxia. Spatial memory performance in the hole board learning task was impaired in anoxic rats when compared with control animals. Attention assessed by the behavioural immobility response to a sudden reduction in background noise was tested in an open field. In anoxic rats this response was reduced compared to controls, which was further reflected in a higher ambulation score in anoxic animals. The emotional state in adult rats after postnatal anoxia was not affected as was demonstrated in the elevated plus-maze and in the shock probe/defensive burying task. The results indicate that adult cognitive deficits after neonatal anoxia are not related to changes in emotional behaviour. Disruption of behavioural attention or the capacity of concentration to task performance may, however, contribute to the observed cognitive impairment.
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Affiliation(s)
- B Buwalda
- Department of Animal Physiology, University of Groningen, The Netherlands
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13
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Jänicke B, Coper H. The effects of prenatal exposure to hypoxia on the behavior of rats during their life span. Pharmacol Biochem Behav 1994; 48:863-73. [PMID: 7972289 DOI: 10.1016/0091-3057(94)90193-7] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
The aim of this study was to investigate the influence of moderate prenatal damage on adaptability during the juvenile, adult, and senile phases. Pregnant rats were exposed to a 12% normobaric hypoxia from day 1 to 17 postconception. Pregnancy was normal in both the treated animals and the controls. Erythrocytes, hemoglobin, and hematocrit did not increase in the treated pregnant animals. During the first 3 weeks, the F1 generation showed developmental deviations in physiological characteristics. Throughout subsequent ontogeny, motor performance, cognitive ability, and adaptability to physical stress were determined with a test battery of varying demands. Some of the differences (e.g., locomotor activity, learning ability) between juvenile untreated and treated rats disappeared during the adult phase. Motor and coordinative abilities, however, remained partially impaired in the old rats, especially under high demands. This study, and previous findings with alcohol (37), indicate that prenatal exposure to a noxa may result in a highly differentiated brain injury pattern. Depending on the different functions, damage may intensify age-dependent adaptive disorders or provoke impairment without influencing the course of development.
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Affiliation(s)
- B Jänicke
- Free University of Berlin, Institute for Neuropsychopharmacology, Germany
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14
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Nyakas C, Buwalda B, Markel E, Korte SM, Luiten PG. Life-spanning behavioural and adrenal dysfunction induced by prenatal hypoxia in the rat is prevented by the calcium antagonist nimodipine. Eur J Neurosci 1994; 6:746-53. [PMID: 8075818 DOI: 10.1111/j.1460-9568.1994.tb00986.x] [Citation(s) in RCA: 27] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
The long-term behavioural effects of prenatal chronic anaemic hypoxia were investigated in young (5 months old), late adult (19 months) and aged Wistar rats (23-26 months). Sodium nitrite (2 g/l) offered in the drinking water during the second half of pregnancy served to evoke prenatal hypoxia. In parallel to nitrite treatment the Ca2+ channel blocker nimodipine (10 mg/kg) or vehicle alone was administered intragastrically once daily. Open-field activity, intermale social behaviour, learning ability in a black-white discrimination paradigm and fear-induced emotionality were assessed at different ages. Plasma corticosterone response to novelty stress was measured by blood sampling through chronic venous canulas at the age of 28 months. The nitrite-exposed 5-month-old offspring started exploration in a novel open-field with considerable delay. This delayed start-latency was augmented in 19- and 23-month-old rats, pointing to exaggerated suppression of behavioural arousal. Nitrite-induced hypoxia decreased the duration of social interactions during ageing. Aged rats exposed to nitrite were unable to learn a black-white discrimination but showed a normal generalized conditioned fear response (immobility) to the test situation as a whole. The conditioned fear-induced vocalization was more frequent among hypoxic aged animals. The aged hypoxic rats displayed a prolonged plasma corticosterone stress response and had higher adrenal weight than their controls. The abnormal open-field, social, learning and emotional behaviours, as well as the altered plasma corticosterone response, were prevented by prenatal nimodipine treatment.
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Affiliation(s)
- C Nyakas
- Central Research Laboratory, Postgraduate Medical University, Budapest, Hungary
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15
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Nyakas C, Buwalda B, Kramers RJ, Traber J, Luiten PG. Postnatal development of hippocampal and neocortical cholinergic and serotonergic innervation in rat: effects of nitrite-induced prenatal hypoxia and nimodipine treatment. Neuroscience 1994; 59:541-59. [PMID: 8008208 DOI: 10.1016/0306-4522(94)90176-7] [Citation(s) in RCA: 52] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
Postnatal development of ingrowing cholinergic and serotonergic fiber patterns were studied in the rat hippocampus and parietal cortex employing a histochemical procedure for acetylcholinesterase as a cholinergic fiber marker, and immunocytochemistry of serotonin for serotonergic fiber staining. The rat pups were killed at postnatal days 1, 3, 5, 7, 10, and 20. The development of cholinergic and serotonergic innervation was described and the fiber density quantified under normal conditions and after long-term prenatal anemic hypoxia induced by chronic exposure to sodium nitrite. Furthermore, a third group was studied in which the nitrite hypoxia was combined with a simultaneous treatment with the Ca(2+)-entry blocker nimodipine to test the neuroprotective potential of this drug. Quantitative measurement of fiber density from postnatal day 1 to day 20 yielded the following results: (i) both neurotransmitter systems revealed an age-dependent and an anatomically-organized developmental pattern; (ii) the serotonergic innervation of the dorsal hippocampus preceded that of cholinergic afferentation in postnatal days 1-3; (iii) prenatal hypoxia induced a transient delay in the innervation of parietal neocortex and dentate gyrus for both neurotransmitter systems, but left the innervation of the cornu ammonis unaffected; and (iv) the hypoxia-induced retardation of cholinergic and serotonergic fiber development was prevented by concomitant application of the Ca(2+)-antagonist nimodipine during the hypoxia. The results indicate that prenatal hypoxia evokes a temporary delay in the cholinergic and serotonergic fiber outgrowth in cortical target areas in a region-specific manner. The hypoxia-induced growth inhibition is prevented by the calcium antagonist nimodipine, which supports the importance of the intracellular Ca2+ homeostasis of cells and growth cones in regulating axonal proliferation.
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Affiliation(s)
- C Nyakas
- Department of Animal Physiology, University of Groningen, Haren, The Netherlands
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16
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Hermans RH, Longo LD. Altered catecholaminergic behavioral and hormonal responses in rats following early postnatal hypoxia. Physiol Behav 1994; 55:469-75. [PMID: 8190763 DOI: 10.1016/0031-9384(94)90102-3] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
We have previously reported alterations in a battery of behavioral functions in the rat following both intermittent and chronic prenatal hypoxia. In this species, the critical brain growth spurt for the catecholaminergic neurotransmitter system takes place in the late gestational and early postnatal period. In addition, postnatal stress can modify adult hypothalamic-pituitary-adrenal responsiveness. Following a given stress, administration of dopaminergic/adrenergic agonists/antagonists may elucidate subtle changes that are not apparent in routine behavioral and endocrine tests. To test the hypothesis that early postnatal hypoxia affects development of the catecholaminergic system and, thus, alters functional outcome, we performed the following study. We exposed 25 litters of Sprague-Dawley rats, each consisting of 10 male pups, to hypoxia (10.5% inspired O2) for 6 h/day (0900 to 1500 h) from postnatal day (P) 2 to 10. We also had 25 control (C) litters. We then performed a series of behavioral tests in immature and mature animals. Body weights were significantly decreased in hypoxic (H) animals from P10 to P100. At P21 we tested locomotor activity in an open-field paradigm with drug challenge (apomorphine, a dopamine receptor agonist, 0.025 and 0.1 mg/kg; or haloperidol, a dopamine receptor antagonist, 0.2 and 0.4 mg/kg). Grooming activity was significantly decreased in H animals at both apomorphine concentrations, compared to controls. Moreover, rearing activity was significantly increased in H animals under basal conditions and when challenged with 0.1 mg/kg apomorphine. Apomorphine (1.0 mg/kg)-induced stereotypy at P39 was significantly increased in H animals compared to controls. Open-field activity at 80 days revealed no significant differences in drug responsiveness between H and C animals.(ABSTRACT TRUNCATED AT 250 WORDS)
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Affiliation(s)
- R H Hermans
- Department of Physiology, School of Medicine, Loma Linda University, CA 92350
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17
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Dell'Anna ME, Luthman J, Lindqvist E, Olson L. Development of monoamine systems after neonatal anoxia in rats. Brain Res Bull 1993; 32:159-70. [PMID: 8348340 DOI: 10.1016/0361-9230(93)90070-r] [Citation(s) in RCA: 43] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
Neurochemical and morphological effects of neonatal anoxia on monoamine systems were studied after 100% N2 exposure for 25 min at 30 h postnatally (postnatal day 2-P2). At 20 min after anoxia, reductions of tissue levels of cerebellar noradrenaline (NA) and striatal dopamine (DA) and metabolites were seen, while 5-hydroxyindoleacetic acid (5-HIAA) was increased in cortex and cerebellum. At P7, NA increased in cerebellum, while serotonin (5-HT) and 5-HIAA decreased in cortex and cerebellum. At P21, increased hippocampal NA and striatal homovanillic acid (HVA) were found, while striatal 5-HT decreased and 5-HIAA increased in striatum and hippocampus. At P60, striatal 3,4-dihydroxyphenylacetic acid (DOPAC) and 5-HIAA levels were found to be enhanced. No effects were seen on 5-HT, tyrosine hydroxylase, or DARPP-32 immunostaining in cortex, hippocampus, and striatum. Thus, the neonatal anoxia induced both acute and persistent neurochemical abnormalities in monoamine systems that were not accompanied by morphological changes detectable with the methods used. The monoamine alterations found could be critically connected to the behavioral disturbances observed in rats after neonatal anoxia. The findings may also be of relevance to dysfunctions seen in humans after perinatal oxygen deficiency, e.g., the attention deficit hyperactivity disorder syndrome.
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Affiliation(s)
- M E Dell'Anna
- Experimental Neurology Laboratory-Institute of Neurology, Catholic University, Rome, Italy
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18
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Luiten PG, Van der Zee EA, Gáspár E, Buwalda B, Strosberg AD, Nyakas C. Long-term cholinergic denervation caused by early postnatal AF64A lesion prevents development of Muscarinic receptors in rat hippocampus. J Chem Neuroanat 1992; 5:131-41. [PMID: 1350200 DOI: 10.1016/0891-0618(92)90039-s] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The effect of early postnatal (day 8) intracerebroventricular injections of the putative cholinotoxin ethylcholine aziridinium mustard (AF64A) on development of cholinergic innervation and postsynaptic muscarinic acetylcholine receptors in the rat hippocampus was examined. The cholinotoxin applied at this stage of development leads to a permanent denervation of cholinergic fibres in the hippocampus in adulthood demonstrated by (immuno)histochemical methods and biochemical assays. Muscarinic receptor expression in the principal neurons of dentate gyrus and cornu ammonis was strongly reduced as studied by immunostaining with antibodies against muscarinic receptor proteins and binding assays with the muscarinic antagonist quinuclidinyl benzilate. Cholinoceptive interneurons and somatostatinergic interneurons are not affected by the developmental cholinergic lesion. Immunoreactivity to protein kinase C type I as a marker for inositolphosphate-related cellular activation systems slightly decreased in the apical dendrites of the hippocampal principal neurons. These findings indicate that damage to ingrowing cholinergic terminals in the hippocampus in the early postnatal period is a critical hazard for development of the muscarinic receptor system in the hippocampal principal neurons. These results are discussed for their significance to the neural mechanisms that underlie perinatal brain damage and associated cognitive dysfunction.
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Affiliation(s)
- P G Luiten
- Department of Animal Physiology, University of Groningen, Haren, The Netherlands
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19
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Gáspár E, Heeringa M, Markel E, Luiten PG, Nyakas C. Behavioral and biochemical effects of early postnatal cholinergic lesion in the hippocampus. Brain Res Bull 1992; 28:65-71. [PMID: 1540847 DOI: 10.1016/0361-9230(92)90232-m] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
The effects of early postnatal (PD 8) intracerebroventricular injection of ethylcholine mustard aziridinium ion (AF64A) on development of open-field and cognitive behaviors and cholinergic markers in several brain areas were examined in the rat. The cholinotoxin was bilaterally administered in a dose range of 0.25 to 2.0 nmol. In the open-field tests, the cholinergic lesion caused a dose-dependent increase in activity at 20 days of age, while it resulted in lengthened latency to initiate exploration and decreased rearing activity at adulthood. Hole-board spatial learning was severely inhibited in adult age. The biochemical activity of choline acetyltransferase (ChAT) and acetylcholinesterase (AChE) in the hippocampus was markedly decreased in a dose-dependent manner, but was unchanged in the neocortex and striatum. Histochemical staining of AChE-positive fibers revealed a severe cholinergic denervation of the granular and pyramidal cell layers of the hippocampus. The results showed that a selective cholinergic deafferentation of the hippocampus at a critical stage of development leads to long-lasting abnormal open-field and spatial learning behaviors.
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Affiliation(s)
- E Gáspár
- Central Research Division, University of Postgraduate Medicine, Budapest, Hungary
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20
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Dell'Anna ME, Calzolari S, Molinari M, Iuvone L, Calimici R. Neonatal anoxia induces transitory hyperactivity, permanent spatial memory deficits and CA1 cell density reduction in developing rats. Behav Brain Res 1991; 45:125-34. [PMID: 1789921 DOI: 10.1016/s0166-4328(05)80078-6] [Citation(s) in RCA: 90] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Physical and reflex development, spontaneous behavior in open field and spatial memory abilities have been studied in rats after neonatal anoxia. Histological analysis of the hippocampal fields have been carried out in selected animals at the end of the testing period. No differences between control and anoxic rats were recorded in the physical and reflex development. Hyperactivity in open field was present in anoxic animals only transiently between P20 and P45. Spatial memory abilities, tested at two developmental stages by means of a maze and a water maze, appeared to be defectual not only during the hyperactivity period but also in adulthood. The histological analysis of the different hippocampal fields demonstrated a significant difference between anoxic and control rats in the cell density of the CA1 field. The present data demonstrate that neonatal anoxia, besides determining only transitory defects in open field behavior, profoundly affects cognitive abilities and cell density in CA1 hippocampal field. These results might be of relevance in the interpretation of the substrate of the cognitive impairment seen in hyperactive children that are exposed to hypoxia at birth.
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Affiliation(s)
- M E Dell'Anna
- Institute of Neurology, Catholic University, Rome, Italy
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21
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Speiser Z, Gordon I, Rehavi M, Gitter S. Behavioral and biochemical studies in rats following prenatal treatment with beta-adrenoceptor antagonists. Eur J Pharmacol 1991; 195:75-83. [PMID: 1676680 DOI: 10.1016/0014-2999(91)90383-2] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Increased motor activity and poor performance in the active avoidance test were observed in the offspring of rats treated with dl-propranolol or sotalol during pregnancy, but not with atenolol and d-propranolol. All substances were administered in drinking water from days 8-22 of gestation. A significant increase in the density of muscarinic acetylcholine receptors in the hippocampus was found for dl-propranolol and sotalol, at 35 and 20 days of age, respectively. Twenty-day-old pups born to dl-propranolol-treated rats exhibited a non-significant decrease in the number of beta-adrenoceptors in the frontal cortex. Assuming that all the beta-adrenoceptor antagonists tested had access to the developing fetal brain, the effect of dl-propranolol and sotalol on behavior could stem from central beta 2-adrenoceptor blockade. In view of the lack of behavioral changes after atenolol, a beta 1-selective adrenoceptor antagonist, it is suggested that the clinical use of beta 1-selective adrenoceptor antagonists during pregnancy might be safer for the fetus than beta 2-adrenoceptor antagonists.
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Affiliation(s)
- Z Speiser
- Department of Physiology and Pharmacology, Sackler Faculty of Medicine, Tel-Aviv University, Ramat Aviv, Israel
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22
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Speiser Z, Uziel J, Defrin-Assa R, Gitter S, Urca G. Different behavioral deficits are induced by anoxia/hypoxia in neonatal and senescent rats: blockade by MK-801. Behav Brain Res 1991; 42:181-6. [PMID: 2059331 DOI: 10.1016/s0166-4328(05)80009-9] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Rats exposed on their first postnatal day to 100% nitrogen for 25 min developed hyperactivity and lower performance in passive avoidance task during development. Administration of MK-801 (0.5 mg/kg i.p.) 1 h before anoxia or (0.25 and 0.5 mg/kg) 1 h after completely reversed this behavioral impairment. Senescent rats (24-26 months) exposed to hypoxia (92% N2 + 8% O2) for 5 h failed in their performance in C.A.R., 30 days later. Pretreatment with MK-801 (1 mg/kg i.p.) completely reversed this impairment. These data suggest that activation of endogenous NMDA receptors produces different behavioral consequences in neonatal and senescent rats and that MK-801 administration close to exposure of animals to anoxia or hypoxia can prevent such damage, thus preventing behavioral impairments in postnatal as well as in senescent rats.
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Affiliation(s)
- Z Speiser
- Department of Physiology and Pharmacology, Sackler School of Medicine, Tel-Aviv University, Israel
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23
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Wigal SB, Amsel A, Wilcox RE. Fetal ethanol exposure diminishes hippocampal beta-adrenergic receptor density while sparing muscarinic receptors during development. BRAIN RESEARCH. DEVELOPMENTAL BRAIN RESEARCH 1990; 55:161-9. [PMID: 2174750 DOI: 10.1016/0165-3806(90)90197-7] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Because of ostensible effects of fetal exposure to ethanol on cardiac and memory functions, beta-adrenergic and muscarinic receptor binding were surveyed in hippocampus and heart in 8- and 17-day-old rat pups. Pregnant, multiparous rats were intubated with either 6 g/kg ethanol or isocaloric dextrose twice daily from gestational days 10-16. At birth, offspring were fostered to untreated mothers. Pups exposed to ethanol had diminished birth weights, although there was no difference in the amount of weight gain by ethanol and control dams during gestation, nor in litter size. Ethanol pups remained smaller than control pups, but this difference was significant only until 8 days of age. At 17 days of age, ethanol pups had fewer hippocampal beta-adrenergic receptors than age-matched controls; muscarinic receptors and CA1 cell densities were not disparate. Parallel studies suggested that approximately 50% of the hippocampal beta-adrenergic receptors in 8-day-olds were of the beta 1 and beta 2 subtypes, while by 17 days of age approximately 70% of the receptors were beta 1. There was an ontogenetic increment in both beta-adrenergic and muscarinic binding from 8 to 17 days of age in hippocampus. No differences between age or drug groups were found in the binding measures in heart tissue. The present findings indicate that fetal ethanol treatment affects developmental measures and beta-adrenergic receptors in the hippocampus in a quasi-selective manner, but not hippocampal CA1-cell density.
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Affiliation(s)
- S B Wigal
- Department of Psychology, University of Texas, Austin 78712
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24
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Speiser Z, Amitzi-Zonder J, Ashkenazi R, Gitter S, Cohen S. Central catecholaminergic dysfunction and behavioural disorders following hypoxia in adult rats. Behav Brain Res 1990; 37:19-27. [PMID: 2310491 DOI: 10.1016/0166-4328(90)90068-p] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Wistar male rats, 3-4 months old, were made to breathe for 6 h a sub-lethal hypoxic atmosphere consisting of 8% oxygen and 92% nitrogen. Following this treatment, these rats were subjected to a series of behavioral and biochemical tests starting 30 days and ending at about 180 days after the hypoxic insult. an age-matched control group was subjected to the same series of tests. The following findings were made at the time interval indicated, relative to controls: (1) At 30-35 days, diurnal (3 h) and nocturnal (12 h) locomotor activities decreased by about 25%. (2) At 40-45 days, amphetamine in the dose range of 0.25-1 mg/kg proved less effective in eliciting an increase in motor activity and stereotypic behavior. (3) At about 50 days, apomorphine in the dose range 0.25-0.5 mg/kg caused an increase in stereotypic behavior. (4) At 60-65 days, alpha-methyl-p-tyrosine at the dose of 50 mg/kg caused a more pronounced hypoactive syndrome and a slower rate of recovery of motor activity. (5) At 75-90 days, performance in the active avoidance test was inferior to that of controls. (6) At 180 days, and one hour after a dose of 200 mg/kg alpha-methyl-p-tyrosine, the turnover rates of hippocampal norepinephrine and caudate-putamen dopamine were much below control. One may tentatively conclude that one of the effects of hypoxia in adult rats is a lesion producing long-term behavioral disorders which are partly ascribed to dopaminergic and, possibly noradrenergic, dysfunction.
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Affiliation(s)
- Z Speiser
- Department of Physiology and Pharmacology, Sackler Faculty of Medicine, Tel Aviv University, Israel
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25
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Represa A, Chanez C, Flexor MA, Ben-Ari Y. Development of the cholinergic system in control and intra-uterine growth retarded rat brain. BRAIN RESEARCH. DEVELOPMENTAL BRAIN RESEARCH 1989; 47:71-9. [PMID: 2736767 DOI: 10.1016/0165-3806(89)90109-0] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
The activity of choline acetyltransferase (ChAT), acetylcholinesterase (AChE), and muscarinic receptors was studied in control rats and in rats growth-retarded in utero because of reduction of the blood supply 5 days before birth. The different markers of the cholinergic system were estimated at P (postnatal day) 6, 9, 12, 15, 22 and 60 in cerebellum, hypothalamus, septum, striatum and CA1, CA3 and fascia dentata of the hippocampus. In control rats, there was a transient increase in ChAT activity in the septum during the second week of postnatal development. In the intrauterine growth retarded rats there was a marked delay in this developmental rise in CA1, CA3 at P6 and P9 and in the fascia dentata at P14 respectively. This delayed rise enzyme activity was associated with a significant reduction of muscarinic binding sites [( 3H]QNB) in the hippocampus. AChE staining showed a similar development in both groups. Therefore, the undernutrition produced by a reduction of the blood supply 5 days before birth is associated with a delayed maturation of cholinergic functions.
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Affiliation(s)
- A Represa
- INSERM U29, Maternité de Port-Royal, Paris, France
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26
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Speiser Z, Amitzi-Sonder J, Gitter S, Cohen S. Behavioral differences in the developing rat following postnatal anoxia or postnatally injected AF-64A, a cholinergic neurotoxin. Behav Brain Res 1988; 30:89-94. [PMID: 3166708 DOI: 10.1016/0166-4328(88)90010-1] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
Rat pups were submitted postnatally to one of two procedures: a 25-min exposure to 100% nitrogen or an i.c.v. bilateral injection of AF-64A, 2 nmol contained in 1-microliter saline. Throughout further development of either group, their performance in passive and active avoidance tests and in amphetamine-induced stereotype behavior was followed and compared. Both groups exhibited hyperactivity which persisted until 42 days of age in the anoxia group and beyond 120 days in the AF-64A group. Both groups were equally inferior to controls in the passive avoidance test, but only the anoxia group was inferior to controls in the active avoidance test. Amphetamine-induced stereotype behavior was much less pronounced in the anoxia group relative to AF-64A-treated rats or to controls. The results suggest that the lesion induced by the neurotoxin is more specific and less widespread than the one caused by anoxia.
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Affiliation(s)
- Z Speiser
- Department of Physiology and Pharmacology, Tel Aviv University, Sackler Faculty of Medicine, Israel
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27
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Russell RW. Behavioral correlates of presynaptic events in the cholinergic neurotransmitter system. PROGRESS IN DRUG RESEARCH. FORTSCHRITTE DER ARZNEIMITTELFORSCHUNG. PROGRES DES RECHERCHES PHARMACEUTIQUES 1988; 32:43-130. [PMID: 2905821 DOI: 10.1007/978-3-0348-9154-7_3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
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Abstract
Wistar rat pups were exposed to 99.99%-nitrogen gas for 10 minutes at 4 days of age, and then their behavior and susceptibility to pentylentetrazol (PTZ) induced seizure were investigated at the ages of 28 and 56 days. Neonatal anoxic rats exhibited hyperactivity in the open field examination and motor coordination disturbance in the inclined screen test, hyperirritability to the startle response and high susceptibility to PTZ at the age of 28 days. However, these behavioral changes and high susceptibility to PTZ were improved with development and there were no longer significant difference from controls rats at 56 days of age except the wire maneuver test. These results suggested that neonatal total anoxia could produce transient dysfunction of the developing brain, including increased susceptibility to seizure and behavioral abnormalities.
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Affiliation(s)
- C Shimomura
- Department of Pharmacology 2, Nagasaki University School of Medicine, Japan
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29
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Grimm VE, Frieder B. The effects of mild maternal stress during pregnancy on the behavior of rat pups. Int J Neurosci 1987; 35:65-72. [PMID: 3623821 DOI: 10.3109/00207458708987111] [Citation(s) in RCA: 51] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
Mild maternal stress in the form of chronic daily subcutaneous injections of saline or the vehicle for diazepam to pregnant rats was shown to result in some long term, subtle but reliable, changes in the behavior of the offspring. The same vehicle given for the same period of time in the dam's drinking water, without injection had no effect on the development of later behavior of rat pups. Chronic prenatal injections of saline or vehicle for diazepam, used in many experiments as controls for the evaluation of drug effects were shown to have some long lasting behavioral effects in the offspring of the treated dams. The series of experiments reported here compared the offspring of saline or vehicle injected dams to those of uninjected dams on a variety of developmental measurements, an open field behaviour and on learning performance in a complex brightness discrimination maze.
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30
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Frieder B, Grimm VE. Prenatal monosodium glutamate causes long-lasting cholinergic and adrenergic changes in various brain regions. J Neurochem 1987; 48:1359-65. [PMID: 3559553 DOI: 10.1111/j.1471-4159.1987.tb05672.x] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
Prenatal monosodium glutamate (MSG) given through the mother's diet was found previously to cause behavioral changes in the offspring, including learning disabilities. In the present study, neurochemical parameters were measured in the brains of prenatally exposed rats at various ages throughout development up to adulthood. At 15 days of age, choline uptake and choline acetyltransferase (ChAT) activity in the frontal cortex were significantly reduced (by 80 and 25%, respectively) in MSG-exposed animals, whereas the same cholinergic parameters in hippocampus were not changed. During later development, choline uptake gradually increased, until in adulthood it became significantly higher in MSG-exposed animals than in the controls. This enhancement was found in both males and females. Our previous study showed that only the male offspring were learning disabled. Choline uptake and ChAT activity were enhanced in the hippocampus of adult male animals. Norepinephrine (NE) uptake was reduced (by 25%) in the frontal cortex of males only. There was no change in NE uptake in the hypothalamus.
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31
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Yamamoto H, Kato T. The effect of neonatal anoxia on brain cholecystokinin-8-like immunoreactivity and monoamine levels of mature rats. Brain Res 1986; 391:285-8. [PMID: 2421854 DOI: 10.1016/0165-3806(86)90294-4] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
The effect of neonatal anoxia upon cholecystokinin-8-like immunoreactivity (CCK-8-I) concentrations was investigated in different brain areas of mature rats. Anoxia within 24 h after birth resulted in significantly lower CCK-8-I levels in the cortex, nucleus accumbens, amygdala and hypothalamus of 10-week-old rats. In contrast, no change was observed in the monoamine levels of these brain areas. The data suggest that neonatal anoxia selectively affects CCK-containing neurons.
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32
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33
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Grimm VE, Frieder B. Differential vulnerability of male and female rats to the timing of various perinatal insults. Int J Neurosci 1985; 27:155-64. [PMID: 4044127 DOI: 10.3109/00207458509149763] [Citation(s) in RCA: 35] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
The results of five experiments showed that exposure to diazepam, hypoxia and monosodium glutamate during the prenatal or early postnatal period of rapid brain development may result in different behavioral consequences depending on the timing of the exposure rather than the nature of the agent. Moreover, male and female offspring may be affected differently by the same agent at different periods of development. Prenatal insults of various kinds impair the later performance of males but not the females in a complex learning task, while postnatal insults seem to affect detrimentally this same behavior in both males and females. The effects of perinatal insults on maze learning and open field activity do not lend themselves to explanation by "feminization" or "masculinization" of behavior caused by interference with prenatal gonadal hormones.
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