Effects of early or late prenatal immune activation in mice on behavioral and neuroanatomical abnormalities relevant to schizophrenia in the adulthood.

Maternal immune activation (MIA) during pregnancy in rodents increases the risk of the offspring to develop schizophrenia-related behaviors, suggesting a relationship between the immune system and the brain development. Here we tested the hypothesis that MIA induced by the viral mimetic polyinosinic-polycytidylic acid (poly I:C) in early or late gestation of mice leads to behavioral and neuroanatomical disorders in the adulthood. On gestational days (GDs) 9 or 17 pregnant dams were treated with poly I:C or saline via intravenous route and the offspring behaviors were measured during adulthood.

Protein-caloric dietary restriction inhibits mossy fiber sprouting in the pilocarpine model of TLE without significantly altering seizure phenotype.

Given the known effects of undernutrition over protein synthesis, we promoted neonatal undernutrition to evaluate its effect over the neuroplasticity induced by the pilocarpine model of epilepsy and also over spontaneous seizure expression. A well-nourished group (WN), fed ad libitum rat chow diet, and an undernourished group (UN), fed 60% of the amount of diet consumed by a WN group, were submitted to status epilepticus (SE) through pilocarpine injection at 45 days of age. Thereafter, animals were behaviorally monitored for 6h daily to quantify seizures.

The role of dorsomedial hypotalamus ionotropic glutamate receptors in the hypertensive and tachycardic responses evoked by Tityustoxin intracerebroventricular injection.

The scorpion envenoming syndrome is an important worldwide public health problem due to its high incidence and potential severity of symptoms. Some studies address the high sensitivity of the central nervous system to this toxin action. It is known that cardiorespiratory manifestations involve the activation of the autonomic nervous system.

Effects of tityustoxin on cerebral inflammatory response in young rats.

Accidents caused by scorpion stings, mainly affecting children, are considered an important cause of morbidity and mortality in tropical countries. Clinical studies demonstrate the relevant role of systemic inflammatory events in scorpion envenoming. However, remains poorly understood whether the major lethal component in Tityus serrulatus venom, tityustoxin (TsTX), is able to induce inflammatory responses in the cerebral microcirculation.

Murine model to study brain, behavior and immunity during hepatic encephalopathy.

Aim: To propose an alternative model of hepatic encephalopathy (HE) in mice, resembling the human features of the disease.

Methods: Mice received two consecutive intraperitoneal injections of thioacetamide (TAA) at low dosage (300 mg/kg). Liver injury was assessed by serum transaminase levels (ALT) and liver histology (hematoxylin and eosin).

Brainstem structures are primarily affected in an experimental model of severe scorpion envenomation.

Severe scorpion envenoming (SSE) is more frequent in children and is characterized by systemic dysfunctions with a mortality rate of up to 9%. Recent evidence shows that the central nervous system (CNS) plays a key role in triggering the cascade of symptoms present in SSE. The age-dependent role of the CNS in SSE lethality may be summarized in 3 hypotheses: (1) the shown increased blood brain barrier permeability of infants to the toxins would especially and primarily compromise neurovegetative control areas, (2) the neurons within these areas have high affinity to the toxins, and (3) the neurovascular interaction is such that SSE metabolically compromises proper function of toxin-targeted areas.

Malnutrition alters the cardiovascular responses induced by central injection of tityustoxin in Fischer rats.

Scorpion envenoming and malnutrition are considered two important public health problems in Brazil, involving mainly children. Both these conditions are more common among the economically stratified lower income portion of the population, thus suggesting that these factors should be analyzed concomitantly. It is known that cardiorespiratory manifestations, as cardiac arrhythmias, arterial hypertension and hypotension, pulmonary edema and circulatory failure are the main "causa mortis" of scorpion envenomation.

Malnutrition during central nervous system growth and development impairs permanently the subcortical auditory pathway.

The brain that grows and develops under the continued influence of malnutrition presents permanent impairment on functioning and neurotransmitter release. The aim of this study was to investigate the chronic effects of neonatal food restriction on neurochemical and neurodynamical aspects within the primary auditory sensory pathway. Our working hypothesis is that neonatal malnutrition may affect the flow of primary sensory information both at a neurochemical and neurodynamical level.

Simultaneous quantitation of nicorandil and its denitrated metabolite in plasma by LC-MS/MS: application for a pharmacokinetic study.

A liquid chromatography-electrospray ionization tandem mass spectrometry method was developed and validated for the simultaneous quantitation of nicorandil and its denitrated metabolite, N-(2-hydroxyethyl)-nicotinamide, in rat plasma. After a liquid-liquid extraction step, chromatographic separation was performed on a ShinPack C(18) column with an isocratic mobile phase composed of methanol and 2 mM aqueous ammonium acetate containing 0.03% (v/v) formic acid (33:67 v/v).

Electroencephalographic evidence of brainstem recruitment during scorpion envenomation.

Scorpion envenomation is a public health problem in Brazil, with most severe cases occuring in children under the age of 5 years (0.6% lethality). In fact, the toxic fractions of the Tityus serrulatus scorpion venom (TSSV) have greater permeability across the BBB of weanling rats when compared to adults.

Carbamazepine is effective in the treatment of 21-day-old Wistar rats injected with Tityus serrulatus crude venom.

The scorpion-envenoming syndrome has an incidence of approximately 8000 accidents/year in Brazil; with most severe cases occurring during childhood and elderly. Previous results from our laboratory suggest that the effects of scorpion toxins on the central nervous system play a major role on the lethality induced by scorpion envenoming. Our group has shown that the pre-treatment with carbamazepine (CBZ) is able to increase the latency-to-death in developing animals inoculated with tityustoxin, a toxic fraction of the Tityus serrulatus crude venom.

Vesicular acetylcholine transporter knock-down mice are more susceptible to pilocarpine induced status epilepticus.

The pilocarpine (PILO) animal model of Temporal Lobe Epilepsy (TLE) portrays the most common changes in hippocampal circuitry found in human TLE. The acute cholinergic insult induces status epilepticus (SE), which triggers an overwhelming set of plastic events that result on late spontaneous recurrent limbic seizures. It has been suggested that the cholinergic system plays an important role in the synchronization required for ictogenesis.

Dose-dependent effect of carbamazepine on weanling rats submitted to subcutaneous injection of tityustoxin.

The scorpion envenoming syndrome is a serious public health matter in Brazil. The most severe cases occur during childhood and elderly. Previous results from our laboratory suggest that the effects of scorpion toxins on the central nervous system play a major role on the lethality induced by scorpion envenoming.

Carbamazepine protects the CNS of Wistar rats against the central effects of scorpion envenomation.

The scorpion envenoming syndrome is a serious public health matter in Brazil. Previous results from our laboratory suggest that the effects of scorpion toxins on the central nervous system play a major role on the lethality induced by scorpion envenoming. The objective of this work is to evaluate carbamazepine (CBZ) as a potential therapeutic agent against tityustoxin (TsTX) envenomation.