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The learning of a conditioned avoidance response, the catecholamine levels in some cerebral structures, and the evolution of the cortical PO2, were studied under hypobaric hypoxia (300 torr) and under normoxia, in rats treated or not with apomorphine, at the dose of 1 or 10 mg/kg i.p. Apomorphine at
We have analyzed a conditioned avoidance response (CAR) in rats, under both normoxia and hypobaric hypoxia (300 torr), to try to elucidate the mechanism of apomorphine's protective effect against hypoxia. The resistance to hypoxia is markedly increased by apomorphine (1 mg/kg i.p.) and, to a lesser
The effects of apomorphine on survival time of mice during lethal anoxic hypoxia were studied. Apomorphine induced hypothermia and an increase in survival time. Both these effects were mediated by cerebral dopamine receptors, however with different affinity for the neuroleptics haloperidol and
Injections of 100 micrograms apomorphine (I.A.) in intact unanaesthetized fetal lambs resulted in the onset of low-voltage electrocortical activity if not already present, onset or an increase in amplitude of fetal breathing movements, and in about 50% of experiments, onset or an increase in
Several evidences suggest that transient global anoxia after Caeraean section birth in rats produces behavioral changes related to dopaminergic transmission. However, all of the reports tested the behavioral changes in adult rats. Here we investigated the role of perinatal anoxia on behavioral
The effectiveness of drugs affecting aminergic triggered motor behaviour was investigated in adult rats oxygen deprived in the early postnatal life. Offsprings were exposed to hypobaric hypoxia (pO2 = 11.6 kPa) from the 2nd till the 10th postnatal day (10 h per day). Hypoxia exposed animals
Brain injury as a result of hypoxia-ischemia remains a common cause of morbidity and mortality in neonates. No effective therapy is currently available. The hematopoietic cytokine erythropoietin (Epo) provides neuroprotection in many adult models of brain injury and is currently being investigated
We studied the effect of apomorphine on the performance of rats, maintained on a free-operant shock-avoidance schedule under normoxic and hypoxic (12, 10, and 8% O2) environments. In a normoxic environment, apomorphine (1, 2, 4, and 8 mg/kg, i.p.) produced stereotyped behaviors and dose-dependent
BACKGROUND
Exposure to hypoxia and isoflurane (Iso) before hypoxia-ischemia has been found to be neuroprotective in neonatal rats. We investigated the long-term effects of delayed preconditioning with Iso, hypoxia, or room air on motor and cognitive function in mice that had 65 min of
Hypothermia may be an ideal neuroprotective intervention in hypoxic-ischemic encephalopathy after perinatal asphyxia. The present study describes the long-term effects of prolonged resuscitative whole-body hypothermia initiated 2 h after hypoxic-ischemic injury on brain morphology and
Survival of 4 days old rats exposed to 6% O2-94% N2 was studied. Administration of L-DOPA (100 mg/kg) or L-5-HTP (100 mg/kg) reduced survival during hypoxia to about 30% of controls. A further reduction of survival time was noted after combined administration of L-DOPA and L-5-HTP. Administration of
Unilateral administration of 6-hydroxydopamine (6-OHDA) into the rat nigrostriatal system provokes circling behavior in response to apomorphine and L-dopa. This behavior appears to be mediated by the development in the lesioned side of a postsynaptic dopamine receptors supersensitivity. Acute
Animals exposed to 6% oxygen showed a partial inhibition of the rate of tyrosine hydroxylation and a blockade of the conditioned avoidance response. The behavioral disruption was suggested to result, at least in part, from a dopaminergic disturbance, since the behavior was restored by the
Transient global anoxia after Cesarean birth in rats may produce alterations in the subcortical DA function and related behaviors. The reports only tested the behavioral changes induced by a general DA agonist, such as amphetamine or apomorphine, in adult rats. Here we investigated the role of
The effects of intravenous administration of agonists and antagonists of dopamine (DA) and norepinephrine (NE) on the central ventilatory response to hypoxia were studied in unanesthetized cats. The experiments were performed in intact animals exposed to CO-hypoxia and in carotid-body denervated