62 research outputs found

    Diabetes and hypertension increase the placental and transcellular permeation of the lipophilic drug diazepam in pregnant women

    Get PDF
    Background: Previous studies carried out in our laboratories have demonstrated impaired drug permeation in diabetic animals. In this study the permeation of diazepam (after a single dose of 5 mg/day, administered intramuscularly) will be investigated in diabetic and hypertensive pregnant women.Methods: A total 75 pregnant women were divided into three groups: group 1 (healthy control, n = 31), group 2 (diabetic, n = 14) and group 3 (hypertensive, n = 30). Two sets of diazepam plasma concentrations were collected and measured (after the administration of the same dose of diazepam), before, during and after delivery. The first set of blood samples was taken from the mother (maternal venous plasma). The second set of samples was taken from the fetus (fetal umbilical venous and arterial plasma). In order to assess the effect of diabetes and hypertension on diazepam placental-permeation, the ratios of fetal to maternal blood concentrations were determined. Differences were considered statistically significant if p=0.05.Results: The diabetes and hypertension groups have 2-fold increase in the fetal umbilical-venous concentrations, compared to the maternal venous concentrations. Feto: maternal plasma-concentrations ratios were higher in diabetes (2.01 ± 1.10) and hypertension (2.26 ± 1.23) groups compared with control (1.30 ± 0.48) while, there was no difference in ratios between the diabetes and hypertension groups. Umbilical-cord arterial: venous ratios (within each group) were similar among all groups (control: 0.97 ± 0.32; hypertension: 1.08 ± 0.60 and diabetes: 1.02 ± 0.77).Conclusions: On line with our previous findings which demonstrate disturbed transcellular trafficking of lipophilic drugs in diabetes, this study shows significant increase in diazepam placental-permeation in diabetic and hypertensive pregnant women suggesting poor transcellular control of drug permeation and flux, and bigger exposure of the fetus to drug-placental transport

    Epilepsy in Dcx Knockout Mice Associated with Discrete Lamination Defects and Enhanced Excitability in the Hippocampus

    Get PDF
    Patients with Doublecortin (DCX) mutations have severe cortical malformations associated with mental retardation and epilepsy. Dcx knockout (KO) mice show no major isocortical abnormalities, but have discrete hippocampal defects. We questioned the functional consequences of these defects and report here that Dcx KO mice are hyperactive and exhibit spontaneous convulsive seizures. Changes in neuropeptide Y and calbindin expression, consistent with seizure occurrence, were detected in a large proportion of KO animals, and convulsants, including kainate and pentylenetetrazole, also induced seizures more readily in KO mice. We show that the dysplastic CA3 region in KO hippocampal slices generates sharp wave-like activities and possesses a lower threshold for epileptiform events. Video-EEG monitoring also demonstrated that spontaneous seizures were initiated in the hippocampus. Similarly, seizures in human patients mutated for DCX can show a primary involvement of the temporal lobe. In conclusion, seizures in Dcx KO mice are likely to be due to abnormal synaptic transmission involving heterotopic cells in the hippocampus and these mice may therefore provide a useful model to further study how lamination defects underlie the genesis of epileptiform activities

    Genetic basis and biotechnological manipulation of sexual dimorphism and sex determination in fish

    Full text link

    Direct rosiglitazone-induced modifications in insulin secretion, action and clearance: a single-dose hyperglycaemic clamp study.

    No full text
    AIMS/HYPOTHESIS: In addition to the improvement in insulin sensitivity, it has been shown that thiazolidinediones modulate beta cell function and insulin clearance in type 2 diabetic subjects. However, interactions between all these actions, and confounding factors due to co-morbidities and co-treatments in diabetic individuals, complicate the identification of specific effects. The aim of this pilot study was to investigate the potential acute effects of rosiglitazone on beta cell function and insulin sensitivity by the hyperglycaemic clamp technique in healthy volunteers. SUBJECTS AND METHODS: Twelve healthy men were included in a randomised, double-blind crossover study. Rosiglitazone (8 mg) or placebo was given orally 45 min before the hyperglycaemic clamp (10 mmol/l for 2 h). RESULTS: The second phase of the insulin response was significantly decreased by rosiglitazone: 13,066 +/- 1,531 vs 16,316 +/- 2,813 pmol l(-1) 110 min in controls (p < 0.05), without change in the first phase. Serum C-peptide was not modified. Rosiglitazone treatment significantly increased insulin clearance (molar ratio of the C-peptide to insulin AUCs: 12.80 +/- 1.34 vs 11.38 +/- .33, p < 0.05) and the insulin sensitivity index (12.0 +/- 1.5 vs 8.5 +/- 1.1 micromol m(-2) min(-1) pmol(-1)l, p < 0.01). CONCLUSIONS/INTERPRETATION: The present results show that a single dose of rosiglitazone rapidly increases insulin clearance and insulin sensitivity index in healthy volunteers, with no direct effect on insulin secretion. The precise mechanisms mediating these actions remain to be determined
    corecore