Developmental iodine deficiency and hypothyroidism impaired in vivo synaptic plasticity and altered PKC activity and GAP-43 expression in rat hippocampus

AbstractTo investigate the mechanism by which developmental iodine deficiency and hypothyroidism affect long-term synaptic plasticity, we chose to study the activity of protein kinase C (PKC) and the expression of growth-associated protein-43 (GAP-43) in pup hippocampus following developmental hypothyroidism. Two developmental hypothyroid rat models were created with iodine-deficient diet (IDD) and water containing methimazole. Compared to the control group, in developmental hypothyroid rats: (i) HFS induced less in vivo LTP and more long-term depression (LTD) in area CA1 on postnatal day (PN) 60 (P 0.05); and (iv) GAP-43 expression was significantly lower (P < 0.01) on both PN30 and PN60. Developmental iodine ...