Search results for "desipramine"
showing 8 items of 28 documents
The effects of the tricyclic antidepressants desipramine, doxepin and iprindole on the isolated perfused rabbit heart.
1974
1. The right sympathetic nerves of isolated perfused rabbit hearts were stimulated electrically (1 msec, supramaximal strength, 15 sec) with increasing frequencies (0.25–20 Hz) at 3 min intervals before and 20 min after starting perfusion with desipramine, doxepin or iprindole. Ventricular rate, right atrial and right ventricular tensions were recorded using the transverse method. 2. Sympathic nerve stimulation caused ventricular arrhythmias in the presence of desipramine (3.3 and 5.0 · 10−6 M) and doxepin (1.6−4.7×10−6 M) but failed to produce arrhythmias in hearts not exposed to drugs, or after iprindole, cocaine and atropine. 3. When desipramine or doxepin was added to Tyrode solution co…
Differential Effects of Fluvoxamine and Other Antidepressants on the Biotransformation of Melatonin
2001
Melatonin, the predominant product of the pineal gland, is involved in the maintenance of diurnal rhythms. Nocturnal blood concentrations of melatonin have been shown to be enhanced by fluvoxamine, but not by other serotonin reuptake inhibitors. Because fluvoxamine is an inhibitor of several cytochrome P450 (CYP) enzymes, the authors studied the biotransformation of melatonin and the effects of fluvoxamine on the metabolism of melatonin in vitro using human liver microsomes and recombinant human CYP isoenzymes. Melatonin was found to be almost exclusively metabolized by CYP1A2 to 6-hydroxymelatonin and N-acetylserotonin with a minimal contribution of CYP2C19. Both reactions were potently in…
Antidepressants are functional antagonists at the serotonin type 3 (5-HT3) receptor
2003
Antidepressants are commonly supposed to enhance serotonergic and/or noradrenergic neurotransmission by inhibition of neurotransmitter reuptake through binding to the respective neurotransmitter transporters or through inhibition of the monoamine oxidase. Using the concentration-clamp technique and measurements of intracellular Ca2+, we demonstrate that different classes of antidepressants act as functional antagonists at the human 5-HT3A receptor stably expressed in HEK 293 cells and at endogenous 5-HT3 receptors of rat hippocampal neurons and N1E-115 neuroblastoma cells. The tricyclic antidepressants desipramine, imipramine, and trimipramine, the serotonin reuptake inhibitor fluoxetine, t…
Neuronal and extraneuronal uptake and efflux of catecholamines in the isolated rabbit heart
1974
1. Isolated rabbit hearts were perfused with (−)-noradrenaline, (−)-adrenaline and (±)-isoprenaline for various time periods (1–180 min) and then washed with an amine-free medium. The venous concentration of the amine was estimated fluorimetrically during the infusion and after its end, to study removal and efflux, respectively. 2. In untreated hearts and after pretreatment with reserpine the removal had a constant rate over 20–60 min. After pretreatment with pargyline to block monoamine oxidase (MAO), however, the removal of noradrenaline declined exponentially to zero. Inhibition of the neuronal uptake (desipramine) and chemical sympathectomy (6-hydroxydopamine) abolished the removal of n…
Characterization of endogenous noradrenaline release from intact and epithelium-denuded rat isolated trachea.
1991
1. Overflow of endogenous noradrenaline (NA) from the in vitro incubated rat trachea evoked by two periods of electrical field stimulation (S1, S2 at 3 or 15 Hz) or by high potassium (60 mM) was determined by high performance liquid chromatography (h.p.l.c.) with electrochemical detection. 2. In the presence of the neuronal uptake inhibitor desipramine, the alpha 2-adrenoceptor antagonist, yohimbine, enhanced the overflow of NA evoked by stimulation at 3 Hz by about 100% suggesting the presence of presynaptic inhibitory autoreceptors on the sympathetic nerves innervating the trachea. 3. When desipramine and yohimbine were present throughout the experiments, the overflow of NA evoked by the …
Differential effects of hypothermia on neuronal efflux, release and uptake of noradrenaline
1972
Isolated rabbit hearts were perfused at 34° (control), 24° or 12°C. The neuronal efflux of noradrenaline after perfusion with the amine for 1 h was depressed at 24° C (Q 10 about 5) in the presence or absence of desipramine; at 12°C the efflux was below the limit of estimation. Moderate reduction of the temperature (24° C) decreased the removal of perfused noradrenaline to about 60% of the control value and caused a 1.7-fold increase of the output of noradrenaline evoked by sympathetic nerve stimulation. It is concluded that the extremely temperature-dependent efflux of noradrenaline across the axonal membrane is not part of the release of noradrenaline evoked by nerve stimulation.
Behavioural responsiveness to picrotoxin and desipramine in adult rats prenatally exposed to different benzodiazepine receptor agonists
1995
The behavioural responsiveness to picrotoxin and desipramine was investigated in adult rats prenatally exposed to different benzodiazepine receptor agonists such as diazepam, alprazolam and zolpidem. Prenatal exposure to diazepam and alprazolam similarly potentiated the anti-immobility effect on the forced swimming test and the inhibitory effect on spontaneous motor activity of picrotoxin and desipramine and increased the seizure sensitivity to picrotoxin. Prenatal zolpidem seems to be ineffective. These data suggest that, despite the differences in their pharmacodynamic profile, prenatal exposure to diazepam and alprazolam, but not zolpidem, may have similar permanent consequences on the b…
From endosomes onwards : membranes, lysosomes and viral capsid interactions
2009
Kirsi Pakkanen haki väitöstutkimuksessaan monitieteellisen lähestymistavan avulla uusia näkökulmia virustutkimukseen. Tutkimus tuo uutta tietoa lipidikalvojen merkityksestä viruksen ja viruksen isäntäsolun elämässä. Tutkimuksessa selvisi, että koiran parvovirus, jota tutkimuksessa käytettiin mallina parvoviruksille ja yleisemmin vaipattomille viruksille, tarvitsee tietynlaisia isäntäsolun lipidikalvojen ominaisuuksia voidakseen vapautua solunsisäisten endosomirakkuloiden sisältä. Erityisen tärkeää tässä vapautumisessa näytti olevan kalvojen juoksevuus sekä jäykkien alueiden hallittu järjestäytyminen kolesterolin avulla. Hyödyntämällä molekyylejä, lääkeaineita, jotka muuttavat kolesteroliavu…