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We previously found that the endogenous anticonvulsant adenosine, acting through [A.sub.2A] and [A.sub.3] adenosine receptors (ARs), alters the stability of currents ([I.sub.GABA]) generated by GABAA receptors expressed in the epileptic human mesial temporal lobe (MTLE). Here we examined whether ARs alter the stability (desensitization) of [I.sub.GABA] expressed in focal cortical dysplasia (FCD) and in periglioma epileptic tissues. The experiments were performed with tissues from 23 patients, using voltage-clamp recordings in Xenopus oocytes microinjected with membranes isolated from human MTLE and FCD tissues or using patch-clamp recordings of pyramidal neurons in epileptic tissue slices. On repetitive activation, the epileptic GABAA receptors revealed instability, manifested by a large [I.sub.GABA] rundown, which in most of the oocytes ([approximately equal to] 70%) was obviously impaired by the new [A.sub.2A] antagonists ANR82, ANR94, and ANR152. In most MTLE tissue-microtransplanted oocytes, a new [A.sub.3] receptor antagonist (ANR235) significantly improved [I.sub.GABA] stability. Moreover, patch-clamped pyramidal neurons from human neocortical slices of periglioma epileptic tissues exhibited altered [I.sub.GABA] rundown on ANR94 treatment. Our findings indicate that antagonizing [A.sub.2A] and [A.sub.3] receptors increases the [I.sub.GABA] stability in different epileptic tissues and suggest that adenosine derivatives may offer therapeutic opportunities in various forms of human epilepsy. epilepsy | focal cortical dysplasia

We examined how the endogenous anticonvulsant adenosine might influence [gamma]-aminobutyric acid type A ([GABA.sub.A]) receptor stability and which adenosine receptors (ARs) were involved. Upon repetitive activation (GABA 500 [micro]M), [GABA.sub.A] receptors, microtransplanted into Xenopus oocytes from neurosurgically resected epileptic human nervous tissues, exhibited an obvious [GABA.sub.A]-current ([I.sub.GABA]) run-down, which was consistently and significantly reduced by treatment with the nonselective adenosine receptor antagonist CGS15943 (100 nM) or with adenosine deaminase (ADA) (1 units/ ml), that inactivates adenosine. It was also found that selective antagonists of A2B (MRS1706, 10 nM) or A3 (MRS1334, 30 nM) receptors reduced [I.sub.GABA] run-down, whereas treatment with the specific A1 receptor antagonist DPCPX (10 nM) was ineffective. The selective A2A receptor antagonist SCH58261 (10 nM) reduced or potentiated [I.sub.GABA] run-down in [approximately equal to]40% and [approximately equal to]20% of tested oocytes, respectively. The ADA-resistant, AR agonist 2-chloroadenosine (2-CA) (10 [micro]M) potentiated [I.sub.GABA] run-down but only in [approximately equal to]20% of tested oocytes. CGS15943 administration again decreased [I.sub.GABA] run-down in patch-clamped neurons from either human or rat neocortex slices. [I.sub.GABA] run-down in pyramidal neurons was equivalent in A1 receptor-deficient and wt neurons but much larger in neurons from A2A receptor-deficient mice, indicating that, in mouse cortex, [GABA.sub.A]-receptor stability is tonically influenced by A2A but not by A1 receptors. [I.sub.GABA] run-down from wt mice was not affected by 2-CA, suggesting maximal ARs activity by endogenous adenosine. Our findings strongly suggest that cortical A2-A3 receptors alter the stability of [GABA.sub.A] receptors, which could offer therapeutic opportunities. A2A receptor | A3 receptor | microtransplantation into Xenopus oocyte | temporal lobe epilepsy

Objective: To assess seizure and cognitive outcomes and their predictors in children (<16 years at surgery) and adults undergoing temporal lobe epilepsy (TLE) surgery in eight Italian centers. Methods: This is a retrospective multicenter study. We performed a descriptive analysis and subsequently carried out multivariable mixed‐effect models corrected for multiple comparisons. Results: We analyzed data from 511 patients (114 children) and observed significant differences in several clinical features between adults and children. The possibility of achieving Engel class IA outcome and discontinuing antiepileptic drugs (AEDs) at last follow‐up (FU) was significantly higher in children (P =.006 and <.0001). However, percentages of children and adults in Engel class I at last FU (mean ± SD, 45.9 ± 17 months in children; 45.9 ± 20.6 months in adults) did not differ significantly. We identified different predictors of seizure outcome in children vs adults and at short‐ vs long‐term FU. The only variables consistently associated with class I outcome over time were postoperative electroencephalography (EEG) in adults (abnormal, improved,odds ratio [OR] = 0.414, P =.023, Q = 0.046 vs normal, at 2‐year FU and abnormal, improved, OR = 0.301, P =.001, Q = 0.002 vs normal, at last FU) and the completeness of resection of temporal magnetic resonance (MR) abnormalities other than hippocampal sclerosis in children (OR = 7.93, P =.001, Q = 0.003, at 2‐year FU and OR = 45.03, P <.0001, Q < 0.0001, at last FU). Cognitive outcome was best predicted by preoperative performances in either age group. Significance: Clinical differences between adult and pediatric patients undergoing TLE surgery are reflected in differences in long‐term outcomes and predictors of failures. Children are more likely to achieve sustained seizure freedom and withdraw AEDs after TLE surgery. Earlier referral should be encouraged as it can improve surgical outcome. [ABSTRACT FROM AUTHOR]

We previously found that the endogenous anticonvulsant adenosine, acting through A2A and A3 adenosine receptors (ARs), alters the stability of currents (IGABA) generated by GABAA receptors expressed in the epileptic human mesial temporal lobe (MTLE). Here we examined whether AR5 alter the stability (desensitization) of IGABA expressed in focal cortical dysplasia (FCD) and in penglioma epileptic tissues. The experiments were performed with tissues from 23 patients, using voltage-clamp recordings in Xenopus oocytes microinjected with membranes isolated from human MTLE and FCD tissues or using patch-clamp recordings of pyramidal neurons in epileptic tissue slices. On repetitive activation, the epileptic GABAA receptors revealed instability, manifested by a large IGABA rundown, which in most of the oocytes (≈70%) was obviously impaired by the new A2A antagonists ANR82, ANR94, and ANR152. In most MILE tissue-microtransplanted oocytes, a new A3 receptor antagonist (ANR235) significantly improved IGABA stability. Moreover, patch-clamped pyramidal neurons from human neocortical slices of periglioma epileptic tissues exhibited altered IGABA rundown on ANR94 treatment. Our findings indicate that antagonizing A2A and A3 receptors increases the IGABA stability in different epileptic tissues and suggest that adenosine derivatives may offer therapeutic opportunities in various forms of human epilepsy. [ABSTRACT FROM AUTHOR]