Nigel R Newberry

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Intracellular recordings from CA1 pyramidal cells in the hippocampal slice preparation were used to compare the action of baclofen, a gamma-aminobutyric acid (GABA) analogue, with GABA. Ionophoretic application of GABA or baclofen into stratum (s.) pyramidale evoked hyperpolarizations associated with reductions in the input resistance of the cell. Baclofen(More)
Baclofen has been used as an antispastic agent for over a decade, yet its mechanism of action is still not fully understood. While early iontophoretic studies revealed a depression of neuronal activity, more recent studies have emphasized a presynaptic depression of transmitter release, both in the peripheral and central nervous system, possibly resulting(More)
1. Human alpha 7 nicotinic acetylcholine (ACh) receptors were expressed in Xenopus oocytes and the effects of the N-methyl-D-aspartate (NMDA) receptor open channel blockers memantine and cerestat on this receptor were examined using two-electrode voltage-clamp recordings and 125I-alpha-bungarotoxin (125I-alpha-bgtx) binding. 2. Memantine and cerestat(More)
Experiments were performed on rat hippocampal CA1 pyramidal cells in vitro in order to elucidate the origin of the late hyperpolarizing potential, which follows the gamma-aminobutyric acid (GABA)-mediated inhibitory post-synaptic potential (GABA-i.p.s.p.). The late hyperpolarizing potential could be evoked by orthodromic stimulation via stratum radiatum or(More)
We have developed an in vitro model of spreading depression (SD) in rat neocortex. KCl application induced a propagating wave of SD associated with a change of optical lucency and an extracellular negative wave. Both of these were abolished by aminophosphonovaleric acid (100 microM), indicating SD's mediation by NMDA receptors. SD abolished(More)
Here we report the existence of burst-firing neurones in the rat dorsal raphe as detected in vivo using intracellular electrophysiological techniques. These neurones discharged single action potentials and doublets or triplets of action potentials in a slow and regular pattern. The apparent input resistance, action potential width and firing threshold of(More)
The four separated isomers of the muscarinic agonist 1, previously known as AF30, have been synthesized by a route that has allowed the absolute stereochemistry of each isomer to be assigned. With the chirality of (-)-camphanic acid known, X-ray analysis of the more crystalline intermediate diastereomeric camphanate 5A allowed the absolute stereochemistry(More)
The pharmacology of two muscarinic responses, recorded from the ventral roots of the spinal cord in the neonatal rat, have been compared: the depolarising response and the inhibition of the monosynaptic compound action potential (CAP). Pirenzepine was more potent than AF-DX 116 in antagonising the depolarising response. However, the potencies of these(More)
N-[2-[4-(2-methoxyphenyl)-1-piperazinyl]ethyl]-N-(2- pyridinyl)cyclohexanecarboxamide trihydrochloride (WAY-100635) is a potent and selective 5-HT1A receptor antagonist in a slice preparation of the guinea pig dorsal raphe nucleus: the inhibitory actions on 5-HT neuronal firing of 5-hydroxytryptamine (5-HT, serotonin), 5-carboxamidotryptamine (5-CT) and(More)
Brain-derived neurotrophic factor (BDNF) (20 ng/ml) significantly enhanced the growth of the somata of GABA-immunoreactive neurones in primary cultures of hippocampal neurones from postnatal rats after only 24h. Whole-cell patch-clamp experiments showed an increase in spontaneous synaptic activity between neurones with time in culture. After 10 days in(More)