Bilateral native nephrectomies for severe hypertension in children with stage 5 chronic kidney disease leads to improved BP control following transplantation.

BACKGROUND: Hypertension is a common problem in stage 5 chronic kidney disease (CKD 5) and following kidney transplantation (KT). There is limited data on the outcome of children with CKD 5 who undergo bilateral native nephrectomies (BNN) for the management of hypertension. METHOD: Retrospective review of 134 children who underwent KT at a single centre over a 10-year period and had a minimum follow up period of 1 year. Children who had undergone BNN for hypertension prior to, and after, KT were identified and their outcome with regard to blood pressure (BP), anti-hypertensive medications and graft function was compared with that of the rest of the cohort. RESULTS: Eleven children (8.2%) underwent BNN, including 2 performed after KT, due to poorly controlled BP despite a median of 3 anti-hypertensive medications. The median age at BNN was 7 years (range 0.5-17 years). All 9 children who underwent BNN prior to KT discontinued anti-hypertensive medication after a median of 6 months and remained normotensive post KT. After a median follow up of 5 years following KT, there was a trend towards lower prevalence of hypertension in children who underwent BNN compared with that of the rest of the cohort (9.1% vs 25%, p 0.23). None of the children who underwent BNN had any evidence of proteinuria, and the median eGFR was 74 ml/min/1.73 m 2 after KT. CONCLUSION: BNN for severe hypertension in CKD 5 is associated with resolution of hypertension prior to KT. It is also associated with a trend towards lower prevalence of hypertension and good graft function following KT.

A juvenile form of postsynaptic hippocampal long-term potentiation in mice deficient for the AMPA receptor subunit GluR-A.

In adult mice, long-term potentiation (LTP) of synaptic transmission at CA3-to-CA1 synapses induced by tetanic stimulation requires L-alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionate (AMPA) receptors containing GluR-A subunits. Here, we report a GluR-A-independent form of LTP, which is comparable in size to LTP in wild-type mice at postnatal day 14 (P14) but diminishes between P14 and P42 in brain slices of GluR-A-deficient mice. The GluR-A-independent form of LTP is sensitive to D(-)-2-amino-5-phosphonopentanoic acid (D-AP5), but lacks short-term potentiation (STP) and can also be observed in the pairing induction protocol. As judged by unaltered paired-pulse facilitation, this LTP form is postsynaptically expressed despite depleted extrasynaptic AMPA receptor pools with reduced levels of GluR-B, which accumulates in somata and synapses of CA1 pyramidal neurons in GluR-A-deficient mice. Our results show that in the developing hippocampus synaptic plasticity can be expressed by AMPA receptors lacking the GluR-A subunit.