Search results for "Monooxygenase"
showing 10 items of 171 documents
Significance of Induction Phenomena
1978
A number of foreign compounds induce the proliferation of the hepatic smooth endoplasmatic reticulum and thereby increase the activity of monooxygenases that metabolize drugs and other foreign compound. With reference to the safety of food additives some antioxidants have been examined by various authors for their inducing capacity, in doses well above those ingested with treated food and above the stipulated accepted daily intake (ADI). Thus feeding of rats with the very high dose of 500 mg/kg body weight of butylated hydroxtoluene (BHT) resulted in an increase in its own oxidative metabolism. Also in monkeys BHT produces an inductive increase of microsomal enzyme activity, cytochrome P 45…
Effect of Monooxygenase Inducers on the Binding of Benzo-(A)Pyrene Metabolites to Cellular Macromolecules in Perfused Rat Lungs
1978
The irreversible binding of metabolically activated [3H]-benzo(a)pyrene (BP) to cellular macromolecules of isolated perfused rat lungs was studied. Lungs from differently pretreated animals were perfused in situ in a recirculating system without ventilation. BP with a specific activity of 10 mCi/μmol was added to 50 ml perfusion medium containing 40% washed bovine erythrocytes to a final concentration of 1 μM. DNA, RNA and protein fractions were isolated and assayed for irreversibly bound radioactivity.
Epoxide Hydrolase Isoenzymes and their Individual Contribution to the Control of Toxic Metabolites
1991
Epoxides are highly strained three membered cyclic ethers which are formed in vivo by the microsomal cytochrome P450 dependent monooxygenases as intermediates of several important biosynthetic pathways (leukotriene A4, squalene 2, 3-oxide) and as metabolites of numerous xenobiotic compounds containing olefinic or aromatic double bonds. Further transformation of these epoxides may occur by either, rearrangement to phenols, aliphatic aldehydes, or ketones; by cytochrome P450 dependent reduction to the parent compound; or by spontaneous or enzymatic conjugation to gluta-thione. Epoxides may also bind covalently to cellular nucleophiles, such as proteins and nucleic acids thus eliciting carcino…
Effect of Antioxidants on Microsomal Enzymes of Rat Liver
1978
Rat diet was supplemented with butylated hydroxytoluene (BHT), butylated hydroxyanisole (BHA) or ethoxyquin (EQ) for 14 days, and hepatic microsomal epoxide hydratase (EH) and monooxygenase were subsequently studied in vitro. The antioxidants increased EH activity. The increase was marked with BHT (factor 3) and EQ (factor 4) and was paralleled by an increase in a protein band on SDS polyacrylamide gels which migrated together with purified rat hepatic EH. A slight but nonsignificant increase in cytochrome P450 content and a moderate increase in ethoxycoumarin deethylation and cytochrome b5 content was also observed while aryl hydrocarbon hydroxylase (AHH) activity was not elevated. Irrever…
Dissimilar Regulation of Antimicrobial Proteins in the Midgut of Spodoptera exigua Larvae Challenged with Bacillus thuringiensis Toxins or Baculoviru…
2015
Antimicrobial peptides (AMPs) and lysozymes are the main effectors of the insect immune system, and they are involved in both local and systemic responses. Among local responses, midgut immune reaction plays an important role in fighting pathogens that reach the insect body through the oral route, as do many microorganisms used in pest control. Under this point of view, understanding how insects defend themselves locally during the first phases of infections caused by food-borne pathogens is important to further improve microbial control strategies. In the present study, we analyzed the transcriptional response of AMPs and lysozymes in the midgut of Spodoptera exigua (Lepidoptera: Noctuidae…
Association analysis between gene variants of the tyrosine hydroxylase and the serotonin transporter in borderline personality disorder.
2010
For patients with borderline personality disorder (BPD), we previously reported an independent effect of the catechol-o-methyl-transferase (COMT) low-activity (Met(158)) allele and an interaction with the low-expression allele of the deletion/insertion (short/long or S/L, resp.) polymorphism in the serotonin transporter-linked promoter region (5-HTTLPR). The purpose of the present study was to extend these findings to the tyrosine hydroxylase (TH) Val(81)Met single nucleotide polymorphism (SNP), the 5-HTTLPR S/L polymorphism incorporating the recently described functional A/G SNP within the long allele of the 5-HTTLPR (rs25531) as well as the variable number of tandem repeat (VNTR) polymorp…
D2-dopamine receptor blockade modulates temporal resolution in goldfish.
2002
A possible effect of dopamine on the temporal resolution of goldfish was investigated in a behavioral, two-alternative, forced-choice procedure. Flicker fusion frequency (FFF) was measured before and after bilateral intravitreal injections of D1- or D2-dopamine receptor (D1-/D2-R) antagonists, or after depletion of retinal dopamine by bilateral intravitreal injections of the dopaminergic neurotoxin 6-hydroxydopamine (6-OHDA). Prior to drug injections, fish achieved FFFs of 33–39 Hz. A D1-R antagonist, SCH 23390, reduced FFF by about 12% (P > 0.1), whereas a D2 antagonist, sulpiride, reduced the relative FFF by 25% (P < 0.03). Depletion of retinal dopamine with 6-OHDA induced a gradual…
Prosurvival effect of human wild-type alpha-synuclein on MPTP-induced toxicity to central but not peripheral catecholaminergic neurons isolated from …
2010
In the present work we report the generation of a new line of alpha-synuclein (alpha-SYN) transgenic mice in which the human wild-type alpha-SYN cDNA is expressed under the control of a tyrosine hydroxylase (TH) promoter. We provide evidence that the ectopic protein is found in TH expressing neurons of both central and peripheral nervous systems. The transgene is expressed very early in development coinciding with the activity of the TH promoter and in the adult brain the human protein distributes normally to the nerve endings and cell bodies of dopaminergic nigral neurons without any evidence of abnormal aggregation. Our results indicate that expression of human wild-type alpha-SYN does no…
The neuroimmune link in the bronchus-associated lymphoid tissue (BALT) of cat and rat: peptides and neural markers.
1991
This light microscopic immunohistochemical study investigates the distribution and target interrelations of nerve fibers in bronchus-associated lymphoid tissues (BALT) of rat and cat by using antisera against (1) the polyneuronal marker protein gene product 9.5 (PGP 9.5), (2) selected opioid and nonopioid peptides, and (3) the marker enzymes tyrosine hydroxylase (TH) and dopamine beta-hydroxylase (DBH). In both species, a similar distribution pattern of PGP, peptide, and catecholamine enzyme immunoreactive was observed. Anti-PGP 9.5 stained all nerve fibers (except some smaller, calcitonin gene-related peptide-immunoreactive (CGRP-ir) fibers presumably of the C-type) throughout the differen…
SEX DIFFERENCES IN THE PATTERN OF CYTOCHROMES P-450 IN RAT LIVER MICROSOMES
1977
ABSTRACT A number of sex differences in the spectral and enzymic properties of rat liver microsomes have been observed which may reflect differences in the population of hepatic cytochromes P 450 of male and female rats: 1. a blue shift in the spectrum of the reduced P 450-CO complex in females as compared to males, 2. lower ΔA max values in the binding of metyrapone to reduced microsomes in females as compared to males, 3. a higher proportion of 2-hydroxylation in the metabolism of biphenyl in females as compared to males, 4. preferential inhibition of ethoxycoumarin deethylation, benzpyrene hydroxylation and biphenyl-4-hydroxylation by α-naphthoflavone in females but by metyrapone in male…