ABSTRACT
We studied the effect of clonal overexpression of neuroligin 3 (NL3) or neuroligin 2 (NL2) in the adult rat cerebral cortex following in utero electroporation (IUEP) at embryonic stage E14. Overexpression of NL3 leads to a large increase in vesicular gamma-aminobutyric acid (GABA) transporter (vGAT) and glutamic acid decarboxylase (GAD)65 in the GABAergic contacts that the overexpressing neurons receive. Overexpression of NL2 produced a similar effect but to a lesser extent. In contrast, overexpression of NL3 or NL2 after IUEP does not affect vesicular glutamate transporter 1 (vGlut1) in the glutamatergic contacts that the NL3 or NL2-overexpressing neurons receive. The NL3 or NL2-overexpressing neurons do not show increased innervation by parvalbumin-containing GABAergic terminals or increased parvalbumin in the same terminals that show increased vGAT. These results indicate that the observed increase in vGAT and GAD65 is not due to increased GABAergic innervation but to increased expression of vGAT and GAD65 in the GABAergic contacts that NL3 or NL2-overexpressing neurons receive. The majority of bright vGAT puncta contacting the NL3-overexpressing neurons have no gephyrin juxtaposed to them, indicating that many of these contacts are nonsynaptic. This contrasts with the majority of the NL2-overexpressing neurons, which show plenty of synaptic gephyrin clusters juxtaposed to vGAT. Besides having an effect on GABAergic contacts, overexpression of NL3 interferes with the neuronal radial migration, in the cerebral cortex, of the neurons overexpressing NL3.
Subject(s)
Cell Adhesion Molecules, Neuronal/metabolism , Cell Movement/physiology , Cerebral Cortex/metabolism , Membrane Proteins/metabolism , Nerve Tissue Proteins/metabolism , Neurons/metabolism , gamma-Aminobutyric Acid/metabolism , Adjuvants, Immunologic , Animals , Cell Adhesion Molecules, Neuronal/genetics , Cells, Cultured , Electroporation , Glutamate Decarboxylase/metabolism , Membrane Proteins/genetics , Nerve Tissue Proteins/genetics , Parvalbumins/metabolism , Rats, Sprague-Dawley , Rats, Wistar , Synapses/metabolism , Transfection , Vesicular Glutamate Transport Protein 1/metabolism , Vesicular Inhibitory Amino Acid Transport Proteins/metabolismABSTRACT
INTRODUCTION: In patients with refractory adrenocorticotropic hormone-dependent Cushing's syndrome,we evaluated steroidogenesis inhibition (SI) and bilateral adrenalectomy (BA) to predict which patients might benefit most from each treatment modality. METHODS: Clinical data from patients treated 1970-2012 were reviewed retrospectively by treatment group (SI or SI+BA). Validated severity scales were used to calculate metabolic (M) score (hypokalemia, hyperglycemia, hypertension, proximal muscle weakness) and adverse events (AE) score (thrombosis, fracture, infection). RESULTS: A total of 65 patients (16 pituitary, 49 ectopic) were treated with SI+BA (n = 21,32%) or SI alone (n = 44,68%). Presenting M scores and source of adrenocorticotropic hormone excess (ectopic versus pituitary) were similar. Both groups improved metabolically after treatment. Over one-third of AEs in the SI+BA group occurred within 12 months of presentation. Half (n = 24, 55%) of the patients treated with SI died (median survival, 24.0 months). Steroid excess contributed to 71% of complications. Six SI+BA patients died (29%), including all 3 patients with recurrent Cushing's syndrome after BA. Minor perioperative complications occurred in 7 patients (33%). CONCLUSION: Posttreatment M and AE scores improved for all patients and 70% of AEs occurred in SI+BA patients within 12 months of presentation, emphasizing the importance of early operative intervention. These data argue for the safety and efficacy of early BA in selected patients with uncontrollable Cushing's syndrome.
