Pannexin-1 channels contribute to seizure generation in human epileptic brain tissue and in a mouse model of epilepsy

Epilepsies are characterized by recurrent seizures, which disrupt normal brain function. Alterations in neuronal excitability and excitation-inhibition balance have been shown to promote seizure generation, yet molecular determinants of such alterations remain to be identified. Pannexin channels are nonselective, large-pore channels mediating extracellular exchange of neuroactive molecules. Recent data suggest that these channels are activated under pathological conditions and regulate neuronal excitability. However, whether pannexin channels sustain or counteract chronic epilepsy in human patients remains unknown. We studied the impact of pannexin-1 channel activation in postoperative human tissue samples from patients with epilepsy displaying epileptic activity ex vivo. These samples were obtained from surgical resection of epileptogenic zones in patients suffering from lesional or drug-resistant epilepsy. We found that pannexin-1 channel activation promoted seizure generation and maintenance through adenosine triphosphate signaling via purinergic 2 receptors. Pharmacological inhibition of pannexin-1 channels with probenecid or mefloquine-two medications currently used for treating gout and malaria, respectively-blocked ictal discharges in human cortical brain tissue slices. Genetic deletion of pannexin-1 channels in mice had anticonvulsant effects when the mice were exposed to kainic acid, a model of temporal lobe epilepsy. Our data suggest a proepileptic role of pannexin-1 channels in chronic epilepsy in human patients and that pannexin-1 channel inhibition might represent an alternative therapeutic strategy for treating lesional and drug-resistant epilepsies.

[Congenital Müllerian anomalies and delivery: analysis of 304 cases between 2000 and 2010 at the University Hospital of Lille]

OBJECTIVES

This study aimed to determine the conditions and way of delivery in women with congenital uterine malformations.

PATIENTS AND METHODS

This retrospective study included a cohort of patients with malformed uterus giving birth in Lille University Hospital between 2000 and 2010, features such as way of delivery, labour, foetal presentation were compared with those patients without uterine malformation.

RESULTS

Patients with uterine anomalies had significantly higher rates of breech présentation (36.51% vs 4.52%; P<0.01) and cesarean section (55.26% vs 18.70%; P<0.01) compared to the group of women with a normal uterus.

DISCUSSION AND CONCLUSION

Our results suggest that women with uterine malformation should be informed that they have an increased risk of caesarean section due to more frequent malpresentations.