INDUCED PROTECTION OF ADRENAL CORTEX AGAINST 7,12-DIMETHYLBENZ[a]ANTHRACENE

7,12-Dimethylbenz[a]anthracene (7,12-DMBA) exerts adrenocorticolytic effects which set it apart from all other polynuclear aromatic hydrocarbons and aromatic amines which have been investigated. Adrenal damage by this compound appears to be due to its steric and electronic properties together with its unusually high solubility in lipides. Many compounds given prior to 7,12-DMBA induced protection of adrenal. The most efficient inducers of protection are flat condensed aromatics possessing 4 or 5 rings; very small doses of these compounds were required to induce protection. Other compounds devoid of these properties induced protection but large or repeated doses were necessary. All inducers of protection had to be given prior to 7,12-DMBA to prevent adrenal necrosis; when given simultaneously with, or later than, this compound adrenal apoplexy resulted. Protective aromatics and 7,12-DMBA as well induced synthesis of menadione reductase in liver. 3-Methylcholanthrene (3-MC) induced this enzyme in many normal organs including liver, lung, adrenal, and in mammary cancer as well. dl-Ethionine under appropriate conditions of time and dosage eliminated the adrenal protection induced by aromatics and also delayed the induction of menadione reductase while depressing the amount of this enzyme which was synthesized. 7,12-DMBA caused a greatly reduced incorporation of tritium from thymidine-H3 into washed acid-insoluble residue of adrenal. 3-MC given in advance mitigated the drastic effect of 7,12-DMBA on DNA synthesis and increased considerably the amount of tritium which was incorporated. The specific damage to adrenal by 7,12-DMBA is a direct effect on cells. Protection of adrenal is a secondary effect which requires induction of protein synthesis and it results in improvement in synthesis of DNA.

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AROMATIC-INDUCED PREVENTION OF FATAL TOXICITY OF 7,12-DIMETHYLBENZ[a]ANTHRACENE

Journal of Experimental Medicine ◽

10.1084/jem.119.6.943 ◽

1964 ◽

Vol 119 (6) ◽

pp. 943-954 ◽

Cited By ~ 20

Author(s):

Charles Huggins ◽

Elizabeth Ford ◽

Ryo Fukunishi ◽

E. V. Jensen

Keyword(s):

Protective Effect ◽

Aromatic Hydrocarbons ◽

Small Dose ◽

Tritiated Thymidine ◽

Lethal Dose ◽

Polynuclear Aromatic Hydrocarbons ◽

Toxic Dose ◽

Highly Efficient ◽

Small Doses ◽

Protection Of Life

Large doses of 7,12-dimethylbenz[a]anthracene (7,12-DMBA) caused the death of rats within 1 day. A small amount of any of 5 polynuclear aromatic hydrocarbons or of an aromatic amine given before the highly toxic dose of 7,12-DMBA resulted in survival for more than 2 months and the specific atrophy of testis which follows 7,12-DMBA was largely prevented. Among the protective aromatics is 7,12-DMBA itself; a small dose of 7,12-DMBA given in advance induced protection of life against an otherwise lethal dose of 7,12-DMBA but only in a proportion of the animals, and testis was not protected from injury. The highly efficient inducers of protection were condensed aromatics composed of 4 or 5 rings. Protection of life against toxicity of big doses of 7,12-DMBA by pretreatment with small doses of aromatics required time (ca. 5 to 8 hours) for its induction. Ethionine given a few minutes after a highly efficient inducer of protection, 3-methylcholanthrene (3-MC), abolished induction of protection; ethionine given 8 hours after 3-MC exerted no influence on its protective effect. A lethal dose of 7,12-DMBA resulted in a considerable reduction in incorporation of tritium in DNA from tritiated thymidine while at the same time synthesis of menadione reductase was induced in liver. A small dose of 3-MC given prior to 7,12-DMBA was advantageous in partially protecting DNA synthesis.

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Multi-alkylated Polynuclear Aromatic Hydrocarbons of Tobacco Smoke: Separation and Identification

Beiträge zur Tabakforschung International/Contributions to Tobacco Research ◽

10.2478/cttr-2013-0452 ◽

1978 ◽

Vol 9 (4) ◽

Cited By ~ 2

Author(s):

M. E. Snook ◽

R. F. Severson ◽

R. F. Arrendale ◽

H. C. Higman ◽

O. T. Chortyk

Keyword(s):

Liquid Chromatography ◽

Cigarette Smoke ◽

Aromatic Hydrocarbons ◽

Ultra Violet ◽

Polynuclear Aromatic Hydrocarbons ◽

Gel Chromatography ◽

Cigarette Smoke Condensate ◽

Gas And Liquid Chromatography ◽

Silicic Acid Chromatography ◽

Derivatives Of

AbstractThe methyl, multi-methyl, and ethyl derivatives of the polynuclear aromatic hydrocarbons (PAH) of cigarette smoke condensate (CSC) were isolated from the neutrals by silicic acid chromatography, solvent partitioning and gel chromatography. The procedure yielded a relatively pure PAH isolate amenable to further identifications. The multi-alkylated PAH were concentrated in the early gel fractions with parent and higher ring PAH found in subsequent gel fractions. It was shown that CSC is very rich in alkylated PAH, and their successful identification required extensive use of gas and liquid chromatography and ultra-violet and GC - mass spectrometric techniques. High-pressure liquid chromatography (HPLC) separated individual isomers of the alkylated PAH in complex GC peaks. PAH from indene to pentamethylchrysene were found. This report concludes our identification studies on the PAH of CSC and complements our two previous reports in this journal. Collectively, our studies have identified approximately 1000 PAH of cigarette smoke condensate and have led to the development of methods for the routine quantitation of PAH in smalI quantities of cigarette smoke condensate.

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Spectrophotometry Measurement of Polynuclear Aromatic Hydrocarbons in Hamilton Harbour Sediments

Water Quality Research Journal ◽

10.2166/wqrj.1991.001 ◽

1991 ◽

Vol 26 (1) ◽

pp. 1-16 ◽

Cited By ~ 4

Author(s):

T.P. Murphy ◽

H. Brouwer ◽

M.E. Fox ◽

E. Nagy

Keyword(s):

Aromatic Hydrocarbons ◽

Total Concentration ◽

Coal Tar ◽

Sediment Cores ◽

Polynuclear Aromatic Hydrocarbons ◽

Mass Spectrometry Analysis ◽

Gas Chromatography Mass Spectrometry ◽

Near Surface ◽

Spectrometry Analysis ◽

Hamilton Harbour

Abstract Eighty-one sediment cores were collected to determine the extent of coal tar contamination in a toxic area of Hamilton Harbour. Over 800 samples were analyzed by a UV spectrophotometric technique that was standardized with gas chromatography/mass spectrometry analysis. The coal tar distribution was variable. The highest concentrations were near the Stelco outfalls and the Hamilton-Wentworth combined sewer outfalls. The total concentration of the 16 polynuclear aromatic hydrocarbons (PAHs) in 48,300 m3 of near-surface sediments exceeded 200 µg/g.

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Charge transfer energies of the complexes of (dibenzoylmethanato)boron difluoride with indeno-pyridines and polynuclear aromatic hydrocarbons

Spectrochimica Acta Part A Molecular and Biomolecular Spectroscopy ◽

10.1016/j.saa.2013.01.089 ◽

2013 ◽

Vol 108 ◽

pp. 181-185 ◽

Cited By ~ 3

Author(s):

Tandrima Chaudhuri ◽

Sneha Salampuria ◽

Pradip Kumar Tapaswi ◽

Chhanda Mukhopadhyay ◽

Subrata Chattopadhyay ◽

...

Keyword(s):

Charge Transfer ◽

Aromatic Hydrocarbons ◽

Polynuclear Aromatic Hydrocarbons ◽

Boron Difluoride

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OESTROGEN-PROGESTERONE RELATIONSHIPS IN THE INDUCTION OF OESTRUS IN SPAYED HEIFERS

Journal of Endocrinology ◽

10.1677/joe.0.0450099 ◽

1969 ◽

Vol 45 (1) ◽

pp. 99-109 ◽

Cited By ~ 31

Author(s):

M. J. CARRICK ◽

J. N. SHELTON

Keyword(s):

Behavioural Response ◽

Normal Response ◽

Oestradiol Benzoate ◽

Small Doses ◽

Refractory State ◽

Increased Sensitivity ◽

Repeated Doses ◽

Effective Doses ◽

Response Line ◽

Normal Sensitivity

SUMMARY Experiments were conducted to examine the behavioural response of spayed heifers to oestrogen, and its modification by progesterone. In two groups of heifers, the median effective doses (MED) of oestradiol benzoate (ODB) were 121 and 132 μg. Repeated doses of ODB at physiological levels did not induce a state of refractoriness; in this respect the heifer is dissimilar to the ewe. However, repeated doses of 10 mg. ODB induced refractoriness to 400 μg. ODB. When such refractory heifers were treated with 10 mg. progesterone/day for 5 days, they showed a normal response to 400 μg. ODB given 3 days later. This return to normal sensitivity was not sustained, and pretreatment with progesterone was necessary for a normal response to subsequent small doses of ODB. The transient removal of the refractory state appears not to be due to a simple synergistic effect of residual progesterone, but to an effect of preconditioning a neural centre to respond to oestrogen. Increasing the duration of pretreatment with progesterone beyond 5 days did not result in a greater sensitivity to ODB. Pretreatment with progesterone in heifers not made refractory to ODB did not result in an increased sensitivity to ODB. Moreover, up to 7 days after termination of the progesterone treatment, the response to ODB was reduced and the slope of the dose-response line was less steep than when ODB was injected alone. The reduction of the response was more pronounced with 40 mg. progesterone/day than with 10 mg. The possible significance of these results in intact animals is discussed.

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