data on the effects of serotonin reuptake inhibitors on learning and memory processes are not consistent. in the present study, the effects of citalopram, a very potent and completely selective inhibitor of the serotonin reuptake on spatial discrimination in the t-maze and morris water maze, were assessed in mice and/or rats. animals received different doses of citalopram (1, 2, 4, 8 or 16 mg/k...

Previous studies have shown that the production of interstitial collagenase by rat myometrial smooth muscle cells is dependent on serotonin. These cells fail to produce collagenase early in culture, however, and produce the enzyme only 8-12 days after confluence. During the early quiescent period, collagenase production can be induced by low concentrations of bacterial endotoxin. Under these co...

Electrochemical methods were used to explore the exocytotic nature of serotonin (5-HT) release in human carcinoid BON cells, an vitro enterochromaffin cell model, understand mechanisms operating gut-derived 5-HT intestinal mucosal epithelium. We show that fractional vesicular cells is 80 % compared previous work pancreatic beta (34 %). The increased from control 87 with preincubation and nearly...

Homeostatic control of volume within the alveolar spaces of the mammary gland has been proposed to involve a feedback system mediated by serotonin signaling. In this article, we describe some of the mechanisms underlying this feedback based on studies of a human normal mammary epithelial cell line (MCF10A) and mouse mammary epithelium. Mammary serotonin was elevated during lactation and after i...

A wealth of pharmacological and behavioral data suggests that spinally projecting serotonergic cells mediate opioid analgesia. A population of medullary neurons, located within raphe magnus (RM) and the neighboring reticular nuclei, contains serotonin and is the source of serotonin in the spinal dorsal horn. To test whether serotonergic neurons mediate opioid analgesia, morphine was administere...

PURPOSE The authors investigate the possible presence of 5-hydroxytryptamine (5-HT1) type serotonin receptors negatively coupled to adenylate cyclase activity in cultured human retinal pigment epithelial (RPE) cells. METHODS Adenylate cyclase activity was assessed by the determination of cellular adenosine 3':5' cyclic monophosphate (cAMP) levels and the effects of serotonin on both basal and...

Sensitization of the gill withdrawal reflex in Aplysia californica is an elementary form of learning, in part resulting from presynaptic facilitation of the LE mechanoreceptor neurons of the abdominal ganglion. It has previously been established that either application of serotonin or direct stimulation of a group of facilitatory neurons, the L29 cells of the abdominal ganglion, can simulate th...

EFFECT OF ISCHAEMIA ON SEROTONIN NEURONES IN THE RABBIT RETINA. CAZEVIEILLE C. and OSBORNE N.N. Nuftield Laboratory of Ophthalmology, University of Oxford, Oxford OX2 6AW, 1J.K. Serotonin is normally not present in sufficient concentrations in the rabbit retina for localisation by inununohistrxhemisby. The amine is taken up by a population of amacrine cells in the intact retina and in primary r...

Serotonin plays important physiological functions at the intestinal level. However, nothing is known concerning its inactivation mechanisms in the human intestine. So, the aim of this work was to characterize the uptake of serotonin at the apical and basolateral membranes of human intestinal epithelial (Caco-2) cells. Uptake of [3H]serotonin at the apical membrane of Caco-2 cells was specific a...

EFFECT OF ISCHAEMIA ON SEROTONIN NEURONES IN THE RABBIT RETINA. CAZEVIEILLE C. and OSBORNE N.N. Nuftield Laboratory of Ophthalmology, University of Oxford, Oxford OX2 6AW, 1J.K. Serotonin is normally not present in sufficient concentrations in the rabbit retina for localisation by inununohistrxhemisby. The amine is taken up by a population of amacrine cells in the intact retina and in primary r...