Metabolism of Benzene in Nonfasted, Fasted, and Aryl-Hydroxylase. Inhibited Rats

Metabolism of Benzene in Nonfasted, Fasted, and Aryl-Hydroxylase. Inhibited Rats

5 Pages · 2003 · 331 KB · English

glucuronide excretion (P < O.OOl), but fasted animals injected with benzene exhibit an increase in glucuronide excretion which is approximately three times the increase noted in nonfasted benzene-injected rats. The administration of P-DDH inhibits the excretion of benzene as the glucuronide (Fig. 1

Metabolism of Benzene in Nonfasted, Fasted, and Aryl-Hydroxylase. Inhibited Rats free download

TOXICOLOGY AND APPLIED PHARMACOLOGY 7, 767771 (1965) Metabolism of Benzene in Nonfasted, Fasted, and ArylHydroxylase Inhibited Rats’ HERBERT H CORNISH AND RICHARD C &~AN Department of Industrial Health, School of Public Health, Institute of Industrial Health, University of Michigan, Ann Arbor, Michigan 48104 Received June 26, 1964 The metabolism of benzene has been intensively studied, and its metabolic fate in the rabbit is well documented (Williams, 1959) Although partially excreted in the expired air, 304076 of ingested or inhaled benzene is hydroxylated and excreted as various phenolic products These may appear in the urine in free or conjugated form Recent studies of the enzymatic hydroxylating mechanism in liver indicate that this enzyme system is present in the microsomal fraction of liver cells (Mitoma et al, 1956) and requires TPNH and oxygen for activity It appears that the hydroxylating enzyme system is also responsible for a number of other metabolic processes, including Ndemethylation A report by Roth and Bukovsky (1961) indicates that the Nde methylating enzyme activity of rabbit liver drops almost to zero after 24 hours of fasting If hydroxylating activity is also depressed to this extent by fasting, then the immediate nutritional state of animals during toxicity testing procedures may play a most important role in determining the degree of toxicity which becomes apparent during the test period One can foresee that aromatic compounds which are hydroxylated to produce metabolites more toxic than the parent compound would have an apparent decreased toxicity in animals unable to hydroxylate the ingested compound Conversely, compounds hydroxylated to yield metabolites which are less toxic than the parent compound would appear more toxic in animals with impaired hydroxylating mechanisms Thus fasting, or the presence of chemical compounds that inhibit hydroxylation, may alter the apparent toxicity of ingested chemicals pDiethyl aminoethyldiphenylpropylacetate hydrochloride” (PDDH) is a compound which has been shown to inhibit the hydroxylating enzyme system (Cook et al, 1954) The present study was designed to determine the effect of fasting and the injection of PDDH on the acute oral toxicity and metabolic fate of benzene METHODS Acute oral toxicity Male SpragueDawley rats of the Holtzman strain, weighing 200250 g, were utilized in the acute toxicity tests Oral toxicity was determined by feeding geometrically graded dosages of reagentgrade benzene3 to groups of 10 rats at each dosage The LDsO and 957% confidence level were calculated by the method 1 This study was supported, in part, by US Public Health Service research grant no MH 03692 from the Institute of Mental Health, National Institutes of Health 2 SKF 525A, Smith, Kline & French Laboratories, Philadelphia, Pennsylvania 3 Mallinckrodt Chemical Works, St Louis, Missouri 767 768 HERBERT H CORNISH AND RICHARD C RYAN of Weil (1952) The LD:,,,‘s of benzene were determined for rats on the following treatments: (a) nonfasted; (b) fasted for 24 hours; (c) nonfasted, but injected with 80 mg/kg of /3DDH intraperitoneally 45 minutes prior to oral administration of benzene; and (d) fasted for 24 hours and injected with 80 mg/kg of PDDH 45 minutes prior to oral administration of benzene Metabolism Male rats similar to those used in the acute toxicity tests, weighing 200250 g, were maintained on a normal test diet4 and in individual metabolism cages designed for the collection of urine uncontaminated by food or feces Complete urine samples were collected by a gentle squeezing of each animal at the end of the ,Xhour period The samples were diluted to 20 ml with water, mixed, filtered, and utilized for the determination of phenols and glucuronides The Dische (1947) method was used for the determination of glucuronides Standard solutions were prepared from recrystallized nglucuronic

------------- Read More -------------

Download metabolism-of-benzene-in-nonfasted-fasted-and-aryl-hydroxylase-inhibited-rats.pdf

Metabolism of Benzene in Nonfasted, Fasted, and Aryl-Hydroxylase. Inhibited Rats related documents

DEPARTMENT of HEALTH and HUMAN - Centers for Disease Control and

507 Pages · 2008 · 6.61 MB · English

influenza, natural disasters, and terrorism, while remaining focused on the threats to health and local, tribal and territorial health network.

A Typology of Victim Characterization in Television Crime Dramas

33 Pages · 2010 · 278 KB · English

her analysis of one season of Law & Order, NYPD Blue, and The Practice. She found that only

Immigration and Economy in the Globalization Process

236 Pages · 2002 · 1.63 MB · English

will need employees with the right skills and motivation. Switching to an active im- Finland by analyzing the development of the volume of foreign-born and foreign na- tionals and direct foreign . In the globalization trend of corporations, competition has shifted from natural re- source and expen

Interpreting sloppy stick figures by graph rectification and

14 Pages · 2001 · 822 KB · English

1 Interpreting sloppy stick figures by graph rectification and constraint-based matching. James V. Mahoney and Markus P. J. Fromherz Xerox Palo Alto Research Center

International Student Guide for Employment in the US

19 Pages · 2012 · 741 KB · English

Problem- If you do not speak English as a native language, you are at a distinct disadvantage communicating with recruiters. Solution- Consciously make an effort to talk with Americans: • Make presentations, take English courses, and work tirelessly at improving your English skills. • Ask a fel

Assistance and Accountability in Externally Managed Schools

37 Pages · 2008 · 263 KB · English

Edison Schools, Inc., is the largest and most visible among a growing number of. Education Management profit EMOs were managing 521 public schools serving nearly 240,000 students across the United . educational services; and management consulting under the “Edison Alliance” flag, through 

List of Developing Nations Afghanistan Albania Algeria Angola

2 Pages · 2011 · 538 KB ·

Algeria. Angola. Antigua and Barbuda. Argentina. Armenia. Azerbaijan Hungary. India. Indonesia. Iran, Islamic Republic of. Iraq. Jamaica. Jordan.

22 NAVAJO NATION COUNCIL | Office of the Speaker

2 Pages · 2013 · 295 KB · English

Law and Order Committee receives update regarding and an additional amount of $1.4 million to ensure operation through operations through the winter season.

Building Permits Granted Development Services Department City of San Antonio

84 Pages · 2012 · 272 KB · English

438 RICHLAND HILLS DR BLDG 10. DL CAMBRIDGE DEV GROUP, INC. (713)961-1336 x. 2251200. NEW 2-STORY MULTI-FAMILY APARTMEN. $947,363.00 2284202. 20x4=80 sq ft at csw, 171 sq ft at approach. $0.00. 3106 PIEDRA DE RIO. PRESIDIO CONST LLC. (210)679-8837 x. 2284203.

Department of History Postgraduate Handbook 2017-18

48 Pages · 2017 · 906 KB · English

Social and cultural change in early modern Ireland; the diffusion of print and the changing experience of . support for their modules ( Social Media. The Department of History has a presence on social Format (e.g., film, video, DVD), that is, the