Previously we reported that prenatal exposure to morphine twice daily during gestation decreases proenkephalin levels in adult progeny within the brain, including the dentate gyrus, and alters mu and delta opioid receptors in the hippocampal CA3 region. The lateral aspect of the perforant path contains and releases enkephalin-derived opioid peptides, and induction of long-term potentiation (LTP...

In this study, involvement ofvoltage-dependent calcium channels in LTP of responses of rat visual cortex slices was analyzed. Field potentials including EPSP1 and EPSP2 from layers II/III were recorded through stimulation of layer IV. Whereas nifedipine, a L-type calcium channel blocker (L-VDCC), did not considerably affect the LTP of responses, but Ni2+, a relatively selective blocker of T-typ...

The induction of long-term potentiation (LTP) in the hippocampal formation can be modulated by different behavioral states. However, few studies have addressed modulation of LTP during behavioral states in which the animal is likely acquiring new information. Here, we demonstrate that both the induction and the longevity of LTP in the dentate gyrus are enhanced when LTP is induced during the in...

The role of the cAMP pathway in LTP was studied in the CA1 region of hippocampus. Widely spaced trains of high frequency stimulation generated cAMP postsynaptically via NMDA receptors and calmodulin, consistent with the Ca2+/calmodulin-mediated stimulation of postsynaptic adenylyl cyclase. The early phase of LTP produced by the same pattern of high frequency stimulation was dependent on postsyn...

In the mammalian brain, LTP is an enduring form of synaptic plasticity that is posited to have a role in learning and memory. Compelling new evidence for this view derives from studies of LTP in the amygdala, a brain structure that is essential for simple forms of emotional learning and memory, such as Pavlovian fear conditioning in rats. More specifically, antagonists of the NMDA receptor bloc...

Current thinking about LTP triggered in the area CA1 of hippocampal slices is ruled by two "dogmas": (1) A single train of high-frequency stimulation is sufficient to trigger short-lasting LTP (1-3 h), whereas multiple trains are required to induce long-lasting LTP (L-LTP, more than 4 h). (2) The development of the late phase of L-LTP requires the synthesis of new proteins. In this study, we fo...

Long-term potentiation (LTP) at synapses of nociceptive nerve fibres is a proposed cellular mechanism underlying some forms of hyperalgesia. In this review fundamental properties of LTP in nociceptive pathways are described. The following topics are specifically addressed: A concise definition of LTP is given and a differentiation is made between LTP and "central sensitisation". How to (and how...

NMDA receptors (NMDARs) are critical mediators of activity-dependent synaptic plasticity, but the differential roles of NR2A- versus NR2B-containing NMDARs have been controversial. Here, we investigate the roles of NR2A and NR2B in long-term potentiation (LTP) in organotypic hippocampal slice cultures using RNA interference (RNAi) and overexpression, to complement pharmacological approaches. In...

Hurst’s seminal characterisation of long-term persistence (LTP) in geophysical records more than seven decades ago continues to inspire investigations into the Hurst phenomenon, not just hydrology and climatology, but many other scientific fields. Here, we present a new theoretical development based on stochastic Hurst–Kolmogorov (HK) dynamics that explains recent finding coefficient increases ...