ABSTRACT We investigated whether oral lactate could prevent seizures and deaths in mice with severe hypoglycemia induced by a high dose of insulin. For this purpose, mice were fasted for 15 h and then given an intraperitoneal injection of regular insulin (5.0 U/kg or 10.0 U/kg). Immediately after insulin injection, the mice received an oral dose of saline (control), glucose (5.5 mmol/kg), or lactate (18.0 mmol/kg). Glucose and lactate levels were measured in the blood and brain before and after the seizures began. Glucose and lactate delayed (p < 0.05) the onset of seizures associated with severe insulin-induced hypoglycemia. Elevated (p < 0.05) brain levels of lactate were associated with an absence of seizures in mice that received glucose or lactate, suggesting that lactate could prevent convulsions associated with severe insulin-induced hypoglycemia. However, the same oral dose of lactate that delayed the onset of convulsions also increased the mortality rate. In contrast, diazepam (3.0 mg/kg) prevented seizures and markedly decreased the frequency of death during severe insulin-induced hypoglycemia. The results demonstrated that in contrast to oral glucose, oral lactate intensifies insulin toxicity.

ABSTRACT We developed a pre-clinical model in which to evaluate the impact of orally administered carbohydrates on postprandial blood glucose levels. For this purpose, we compared the effects of different carbohydrates with well-established glycemic indexes. We orally administered (gavage) increasing amounts (0.2, 0.4, 0.6, 0.8, and 1.0 g/kg) of sucrose and lactose to rats which had been fasted for 6 h or 15 h, respectively. In part of the experiments we administered frutose (gavagem). Three different models were compared for measuring postprandial blood glucose levels: a) evaluation of interstitial glucose concentrations by using a real time continuous glucose monitoring system; b) evaluation of glucose levels in blood obtained from the rat tail; c) evaluation of serum glucose levels in blood collected after decapitation. Our results showed that blood obtained from the tails of 15-h fasted rats was the best model in which to evaluate the effect of carbohydrates on postprandial blood glucose levels.

Os autores realizaram 200 punções cervicais laterais em pacientes comatosos sem agitação psicomotora, comprovando ser este novo método uma alternativa da punção sub-occipital, tendo sido bem sucedidos em 90% dos casos. Os acidentes hemorrágicos ocorridos foram do tipo venoso e de pequena intensidade, não causando quaisquer efeitos colaterais aos pacientes, nem alterações na realização do exame do LCR. Picada da artéria vertebral não foi observada. Punções em cadáveres demonstraram que essa artéria dista um centímetro anteriormente ao trajeto da agulha para a realização da punção.

200 cervical lateral punctions (CLP) were performed in comatose patients without psychomotor trouble proving this new system to be an alternative for suboccipital punction. This procedure was successful in 90% of the cases. Low importance venous accidents happened but they did not bring any injury or serious consequences to the patients or to cerebrospinal fluid examination results. Vertebral artery injury was not observed. Punctions in corpses showed us that this artery is one cm far from the needle trajectory during the realization of the CLP.