Pierre Poulain

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The median eminence (ME), which is the common termination field for adenohypophysiotropic systems, has been shown to produce nitric oxide (NO), a signaling molecule involved in neuroendocrine secretion. Using an ex vivo technique, 17beta-estradiol exposure to ME fragments, including vascular tissues, stimulated NO release within seconds in a(More)
The activation of nitric oxide (NO) signaling pathways in hypothalamic neurons plays a key role in the control of GnRH secretion that is central to reproductive function. It is unknown whether NO directly modulates the firing behavior of GnRH neurons in the preoptic region of the mature brain. Using patch-clamp recordings from GnRH neurons expressing green(More)
Galanin may act in the regulation of reproduction and feeding behaviour through a direct action on arcuate nucleus (ARC) neurones but evidence for a postsynaptic action is absent. The effects of rat galanin(1-29) on rat ARC neurones were examined during recordings with biocytin-filled sharp microelectrodes from brain slices. Neurones were subsequently(More)
 The guinea-pig hypothalamic magnocellular dorsal nucleus (mdn) exclusively contains enkephalinergic neurones providing inputs to the septum. This nucleus is believed to play a role in hippocampo-septo-hypothalamic relationships. mdn neurones display prominent low-threshold Ca2+ spikes, which differ in their propensity to trigger either a burst of Na+(More)
The efferents of enkephalin-immunoreactive neurons in the magnocellular dorsal nucleus of the guinea-pig were studied using different neuroanatomical methods and indirect immunocytochemical technique. Following unilateral implantation of the fluorescent dye 4',6-diamidino-2-phenylindole in the lateral septal nucleus, retrogradely-labeled perikarya were(More)
The amyloid-beta-protein (A beta P) is the major component of the amyloid deposition which characterizes Alzheimer's disease. We have investigated the effects of 25-35 A beta P, the biologically active part of A beta P, on 35 lateral septal neurons in slices of guinea-pig brain during intracellular recording. Bath application of 25-35 A beta P (10(-6) M)(More)
Membrane properties of 174 neurons were studied in the mediolateral part of the lateral septum (LSml) using an in vitro slice preparation of guinea-pig brain. Intracellular recordings were correlated with morphological data obtained from 34 neurons intracellularly stained with horseradish peroxidase (HRP). Neurons were divided into three classes according(More)
It is becoming increasingly apparent that non-neuronal cells play a critical role in generating and regulating the flow of information within the brain. Among these non-neuronal cells, astroglial cells have been shown to play important roles in the control of both synaptic transmission and neurosecretion. In addition to modulating neuronal activity,(More)
From guinea-pig hypothalamic slices, intracellular studies demonstrate the existence of neurons responding to depolarizing current pulses by bursts of fast spikes riding on slow depolarizing potentials, when activated at the resting potential or from hyperpolarized levels (44 cells). Slow depolarizing potentials have a mean amplitude of 17.6 mV and a mean(More)