Evidence accumulated from clinical and basic research has indirectly implicated the insulin receptor (IR) in brain cognitive functions, including learning memory (Wickelgren, I. (1998) Science 280, 517–519). The present study investigates correlative changes IR expression, phosphorylation, associated signaling molecules rat hippocampus following water maze training. Although distribution of protein matched that mRNA most forebrain regions, a dissociation expression patterns was found...

Learning behavior similar to vertebrate classical conditioning was demonstrated for the mollusc Hermissenda crassicornis. Postsynaptic membrane changes within well-defined neural systems that mediate learning play a casual role in recording learned association later recall. Specific ionic currents tissue undergo transformations lasting days after associative training with physiologic stimuli. During acquisition intracellular calcium increases; this increase is accompanied by specific...

Alzheimer's disease (AD) characteristically presents with early memory loss. Regulation of K + channels, calcium homeostasis, and protein kinase C (PKC) activation are molecular events that have been implicated during associative which also altered or defective in AD. PKC is involved the processing amyloid precursor (APP), a central element AD pathophysiology. In previous studies, we demonstrated benzolactam (BL), novel activator, reversed channels defects enhanced secretion APPα cells. this...

The recent demonstration of K+ channel dysfunction in fibroblasts from Alzheimer disease (AD) patients and past observations Ca(2+)-mediated modulation during memory storage suggested that AD, which is characterized by loss other cognitive deficits, might also involve intracellular Ca2+ mobilization. Bombesin-induced release, inositol trisphosphate-mediated, shown here to be greatly enhanced AD compared with control groups. Bradykinin, another activator phospholipase C, elicits similar...

Intracellular recordings were made from hippocampal CA1 pyramidal neurons within brain slices of nictitating membrane conditioned, pseudoconditioned, and naive adult male albino rabbits. All included (26 26 28 naive) had stable penetration at least 60 mV action potential amplitudes. Mean input resistances approximately equal to mu omega for the three groups. A marked reduction in afterhyperpolarization (AHP) following an impulse was apparent conditioned (x = -0.98 mV) as compared...

Activation of protein kinase C (PKC) can mimic the biophysical effects associative learning on neurons. Furthermore, classical conditioning rabbit nictitating membrane (a form learning) produces translocation PKC activity from cytosolic to compartments CA1 region hippocampus. Evidence is provided here for a significant change in amount and distribution within cell field hippocampus that specific learning. This seen at 1 day after as focal increments [ 3 H]phorbol-12,13-dibutyrate binding...

A single identified neuron was repeatedly isolated by axotomy from the central nervous system of nudibranch mollusk Hermissenda crassicornis. An early voltage-dependent outward K+ current this reduced and more rapidly inactivated for animals previously trained with paired but not randomized light rotation. Since change can affect interneuron motorneuron output via known synaptic pathways, it helps explain a long-lasting behavioral that shows defining features vertebrate associative learning.

Among the pathologic hallmarks of Alzheimer's disease (AD) neurodegeneration, only synaptic loss in brains AD patients closely correlates with degree dementia vivo. Here, we describe a molecular basis for this synapses: pathological reduction synaptogenic PKC isozymes and their downstream substrates, such as brain-derived neurotrophic factor. This reduction, particularly α ε, occurs association elevation soluble β amyloid protein (Aβ), but before appearance plaques or neuronal Tg2576...

Evidence has shown that the insulin and receptor (IR) play a role in cognitive function. However, detailed mechanisms underlying insulin's action on learning memory are not yet understood. Here we investigated changes long-term memory-associated expression of IR downstream molecules rat hippocampus. After consolidation following water maze experience, gene showed an up-regulation CA1, but down-regulation CA3 region. These were correlated with significant reduction hippocampal protein levels....

1. The afterhyperpolarization (AHP) that follows action potentials was studied in CA1 hippocampal pyramidal cells from classically conditioned and control rabbits. Measurements of the AHP were obtained with intracellular recordings within slices. 2. rabbit found to be accompanied by a conductance increase. reduced bath applications calcium channel blockers, cadmium cobalt, application cholinergic agonist, carbamylcholine chloride, injection chelator, ethylene glycol-bis(B-aminoethyl...

Many experiments in the past have demonstrated requirement of de novo gene expression during long-term retention learning and memory. Although previous studies implicated individual genes or genetic pathways memory, they did not uncover collective behaviors patterns genes. We used genome-scale screening to analyze spatial rats Morris water maze. Our results show distinct temporal profiles associated with Exogenous administration one peptide whose sustained increase memory was by microarray...

The nudibranch mollusk Hermissenda crassicornis is normally attracted to a test light. Three days of training consisting 50 trials per day light paired with rotational stimulus led significant increase, lasting for days, in the animal's response latency enter group that received associated rotation was significantly different from groups subjected nonassociative control procedures. Modifications well-known sensory networks may be related behavioral change shares several operational features...

Three days of training consisting trials light paired with rotation produces a long-term modification photopositive behavior in Hermissenda crassicornis. The behavioral depends on the temporal association and rotation. For animals that received rotation, significant increases spontaneous activity type B photoreceptors were correlated changes after training. A persistent tonic depolarization can explain cellular produced by

The role of the Ca2+/phospholipid-dependent, diacylglycerol-activated enzyme protein kinase C (PKC) in rabbit eyelid conditioning was examined. PKC partially purified from CA1 region hippocampal slices naive, pseudoconditioned, and conditioned rabbits 24 hr after were well conditioned. Crude membrane cytosol fractions prepared. In rabbits, significantly more activity (63.3%) associated with fraction (and less fraction) compared to naive (42.0%) pseudoconditioned (44.7%) animals. These...

Using both scanning confocal and electron microscopic morphometric measurements, we analyzed single dendritic spines of CA1 pyramidal cells in the hippocampi water maze-trained rats vs. controls. Two days after completion all training, observed a memory-specific increase number mushroom spines-all which make synaptic contacts-but not numbers filopodia or stubby thin spines, as quantified with double-blind protocols images. This spine was enhanced by PKC activator candidate Alzheimer's...