Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “Indophenol”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 793 records · Page 44Linked to original sources
PubMed1998

Analysis of the 5-HT2 receptor ligands dimethoxy-4-indophenyl-2-aminopropane and ketanserin in ethanol discriminations.

Previous studies have suggested a modulatory role of the 5-HT2 receptor system in the behavioral effects of ethanol. The present study examined the discriminative stimulus effects of the 5-HT2A/2C agonist (-)-dimethoxy-4-indophenyl-2-aminopropane (DOI) and the 5-HT2A antagonist ketanserin in rats trained to discriminate either 1.5 g/kg of ethanol from water (intragastrically, n = 7) or 2.0 g/kg of ethanol from water (intragastrically, n = 8). In substitution tests, neither DOI (0.3 to 1.0 mg/kg, i.p.) nor ketanserin (3.0 to 17.0 mg/kg, i.p.) produced discriminative stimulus effects similar to either training dose of ethanol, although decreases in rates of responding were significant at the highest doses tested. Likewise, when given in combination with ethanol, neither 5-HT2 ligand shifted the ethanol-dose response determination in either the 1.5 or 2.0 g/kg ethanol training groups. DOI in combination with ethanol did not alter rates of responding, whereas ketanserin in combination with ethanol significantly decreased response rates. Thus, the 5-HT2A receptor ligands do not appreciably affect the discriminative stimulus effects of ethanol, in contrast to previous results with 5-HT1B ligands.

Animals↗
PubMed2003

Chronic fluoxetine differentially affects 5-hydroxytryptamine (2A) receptor signaling in frontal cortex, oxytocin- and corticotropin-releasing factor-containing neurons in rat paraventricular nucleus.

Differential adaptive changes in serotonin2A [5-hydroxytryptamine (5-HT)2A] receptor signaling during treatment may be one mechanism involved in the latency of therapeutic improvement with antidepressants, such as fluoxetine. We examined the effects of fluoxetine (2, 3, 7, 21, or 42 days) on hypothalamic 5-HT2A receptor signaling. The hormone responses to an injection of the 5-HT2A receptor agonist (+/-)-1-(2,5-dimethoxy-4-iodophenyl)-2-amino-propane HCl (DOI) were used as an index of hypothalamic 5-HT2A receptor function. Treatment with fluoxetine for 21 or 42 days produced diminished adrenocorticotropic hormone (ACTH) and oxytocin (but not corticosterone) responses to DOI injections (2.5 mg/kg i.p.; 15 min postinjection). Regulators of G protein signaling 4 and Galphaq protein levels in the hypothalamic paraventricular nucleus were not altered during fluoxetine treatment. Because previous studies indicate that treatment with fluoxetine for 21 days resulted in increased hormone responses to DOI when measured at 30 min after injection, we examined the effect of fluoxetine (21 days) on DOI-induced increase hormone levels at 15, 30, and 60 min after DOI injection. Fluoxetine decreased the oxytocin response at 15 but not at 30 min post-DOI injection, and potentiated the ACTH and corticosterone responses at 30 min post-DOI injection. For comparison, we examined the effect of fluoxetine on 5-HT2A receptor-mediated increase in phospholipase C (PLC) activity in the frontal cortex. 5-HT-stimulated, but not guanosine 5'-O-(3-thio)triphosphate-stimulated PLC activity was increased after 21 days of fluoxetine-treatment. Overall, these results indicate that chronic fluoxetine treatment can potentiate 5-HT2A receptor signaling in frontal cortex but differentially alters 5-HT2A receptor signaling in oxytocin-containing neurons and corticotropin-releasing factor-containing neurons in the paraventricular nucleus.

Animals↗
PubMed1969

New light-sensitive cofactor required for oxidation of succinate by Mycobacterium phlei.

Irradiation of the electron transport particles of Mycobacterium phlei with light at a wavelength of 360 manometers resulted in a loss of oxidase activities of succinate and the reduced form of nicotinamide adenine dinucleotide. The lesion in the two pathways caused by irradiation of the particles differs. The succinoxidase pathway was more labile to irradiation than the pathway linked to nicotinamide adenine dinucleotide. Restoration of succinoxidase activity (up to 50 to 60 percent) occurred on addition of a thermostable, water-soluble material obtained from Mycobacterium phlei cells or with an extract of mitochondria from boiled rat liver. Other known cofactors, such as flavine adenine dinucleotide, flavine mononucleotide, benzo- and naphthoquinones, as well as sulfhydryl agents, failed to restore succinoxidase activity after irradiation. Water-soluble material from Mycobacterium phlei appears to function between the flavoprotein and cytochrome b on the succinoxidase pathway. In contrast to the requirements for restoration of the pathway linked to nicotinamide adenine dinucleotide, restoration of succinoxidase does not occur with quinones or other cofactors such as flavine adenine dinucleotide.

Animals↗
PubMed1972

Chemical and physical characteristics of the deoxycholate-soluble and magnesium-reaggregated membrane nicotinamide adenine dinucleotide (reduced form) oxidase of Bacillus megaterium.

The inactive components of the nicotinamide adenine dinucleotide (reduced form) (NADH) oxidase present in the 0.4% deoxycholate-soluble fraction obtained from Bacillus megaterium KM membranes were reaggregated into active NADH oxidase by dilution in the presence of Mg(2+). The reaggregated oxidase was different from the original membrane with respect to sedimentation behavior in a sucrose gradient and morphological appearance. The deoxycholate-insoluble portion of the membrane had membrane-like structure whereas the reaggregated oxidase appeared to be a filamentous aggregate of small particles. The reaggregated oxidase and the deoxycholate-insoluble membrane residue were similar to the original membrane with respect to total protein and total lipid content. The inactive components of the NADH oxidase system exist in deoxycholate as two molecular species which were separable by sucrose density gradient centrifugation or gel filtration in deoxycholate-containing solutions. Both components and dilution in the presence of Mg(2+) were necessary for restoration of oxidase activity. The smaller-molecular-weight component contained all of the NADH-2,6-dichlorophenolindophenol oxidoreductase activity of the original membrane.

Bacillus megaterium↗
PubMed1972

Separation of the primary dehydrogenase from the cytochromes of the nicotinamide adenine dinucleotide (reduced form) oxidase of Bacillus megaterium.

A selective extraction procedure was developed for sequentially extracting a fraction containing the primary dehydrogenase and a fraction containing the cytochromes of the nicotinamide adenine dinucleotide (reduced form) (NADH) oxidase of Bacillus megaterium KM membranes. The primary dehydrogenase (NADH-2,6-dichlorophenolindophenol oxidoreductase) activity was extracted from sonically treated membranes with 0.4% sodium deoxycholate for 30 min at 4 C. The insoluble residue was extracted with 0.4% sodium deoxycholate in 1 m KCl for 30 min at 25 C. A combination of the two extracts and dilution in Mg(2+) gave good recovery of the original membrane NADH oxidase activity. The primary dehydrogenase fraction contained 41% of the membrane protein, no cytochromes, flavine adenine dinucleotide as the sole acid-extractable flavine, and most of the membrane ribonucleic acid (RNA). The cytochrome-containing fraction had 16% of the membrane protein, 61% of the membrane cytochrome with the same relative amounts of cytochromes a and b as the original membrane, no acid-extractable flavine, little RNA, and no oxidoreductase activity. The oxidoreductase fraction remained soluble after removal of deoxycholate whereas the cytochrome fraction became insoluble after removal of deoxycholate-KCl, but the precipitated fraction could be redissolved in 0.4% sodium deoxycholate. Treatment of both fractions with ribonuclease to destroy all of the RNA present did not affect the ability of the fractions to recombine into a functional oxidase unit. Treatment of either fraction with phospholipase A prevented restoration of a functional oxidase when the oxidoreductase and cytochrome fractions were treated in solution, but no affect on restoration of oxidase was observed when the phospholipase A treatment was carried out with the soluble oxidoreductase fraction and the insoluble cytochrome fraction.

Bacillus megaterium↗