Anne M Simpson

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The hypothalamic suprachiasmatic nucleus (SCN) is a circadian oscillator that receives a dense serotonergic innervation from the median raphe nucleus. Serotonin (5-HT) modulates the effects of light on circadian behavior by acting on 5-HT1B receptors on retinohypothalamic (RHT) terminals in the SCN. Activation of 5-HT1B presynaptic receptors on RHT(More)
The hypothalamic suprachiasmatic nucleus (SCN) is a circadian oscillator that receives glutamatergic afferents from the retina and serotonergic afferents from the midbrain. Activation of presynaptic serotonin 1B (5-HT1B) receptors on retinal terminals in the SCN inhibits retinohypothalamic neurotransmission and light-induced behavioral phase shifts. To(More)
In rats anesthetized with pentobarbital or a mixture of urethane and chloralose, horseradish peroxidase (HRP) was injected into the intermediolateral column of the spinal cord (Th7 and Th9) or the posterior pituitary lobe. HRP positive cells were found mainly in the dorsomedial part of the paraventricular nuclease (PVN) of the spinal injected animals. These(More)
Whether secretion of gastric acid (GAS) is in response to peripheral and/or central administration of chemical or electrical stimuli can be differentiated by vagotomy. GAS has been shown to be controlled by specific lateral hypothalamic (LHA) neurons. Application of 2-deoxy-D-glucose (2-DG) or insulin to the LHA by microinjection or iontophoresis has(More)
Electroosmotic applications of 2-deoxy-D-glucose (2-DG) were made in the lateral hypothalamus (LHA). Changes in LHA unit activity and concomitant gastric acid secretion were then observed 2-DG responsive neurons tended to form two clusters in the LHA. Electroosmotic application induced four patterns of activity change in different LHA neurons. Gastric acid(More)
Gastrin related peptides (PG) affected neurons in the lateral hypothalamus (LHA) differently in food deprived than in non-deprived rats. Electroosmosis and intravenous (IV) results agreed. Gastric acid secretion was also measured. Neural responses to PG were: transiently increased discharge rate followed by desensitization occurred equally in deprived and(More)
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