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1.
Environ Monit Assess ; 193(4): 159, 2021 Mar 04.
Article in English | MEDLINE | ID: mdl-33660097

ABSTRACT

Mansa district in Malwa region of South-West Punjab has gained significant attention due to elevation in number of patients suffering from diverse diseases especially cancer and consumption of contaminated groundwater could be one of the possible reasons. The present study reports the assessment of 59 groundwater samples from Mansa district by evaluating physicochemical characteristics, potentially toxic element (PTE) contamination and associated health implications followed by analysis of water quality status using various indices. Multivariate statistics were applied for source identification of PTEs in groundwater. The study revealed occurrence of PTEs with mean (µg L-1) dominance order of As (650.8) > U (104.14) > Zn (55.3) > Fe (34.4) > Hg (8.3) > Mn (5.1) > Cu (4.1) > Cr (2.7) > Pb (2.4). One hundred and 71.19% groundwater samples were found to be seriously contaminated with As and U, respectively, and posing high cancer risks to local residents via ingestion. Higher hazard indices of 16.64 and 12.85 for children and adults, respectively, indicated high non-carcinogenic health risks to both population groups but children were observed to be more vulnerable. Correlation analysis showed positive correlations of U with total dissolved solids (TDS), fluoride (F-) and total alkalinity (TA). Principal component analysis (PCA) and cluster analysis (CA) revealed the contribution of both geogenic (weathering of rocks) and anthropogenic sources (overuse of agrochemicals in agricultural lands and release of inefficiently treated industrial effluents) for deteriorating the groundwater quality of study area. The study counsels the inhabitants to consume treated groundwater as ingestion route was identified as the primary route of exposure.


Subject(s)
Groundwater , Metals, Heavy , Water Pollutants, Chemical , Adult , Child , Environmental Monitoring , Humans , India/epidemiology , Metals, Heavy/analysis , Risk Assessment , Water Pollutants, Chemical/analysis
2.
Spectrochim Acta A Mol Biomol Spectrosc ; 206: 367-377, 2019 Jan 05.
Article in English | MEDLINE | ID: mdl-30157444

ABSTRACT

In the present paper, transparent and non-toxic Bi2O3-B2O3 glasses doped with BaO have been prepared by the authors which may replace the standard radiation shielding concretes and lead based commercial glasses for gamma ray shielding applications. The effects of BaO on the structural and optical properties of the prepared glass system have been investigated by Raman, FTIR and UV-Visible techniques. It has been observed that barium plays the role of a modifier and it is responsible for conversion of triangular [BO3] units to tetrahedral [BO4] units along with formation of non-bridging oxygen and increase in ionic character. It also improves the radiation shielding abilities of the glass system. The mass attenuation coefficients for gamma-ray photons at 662 keV energy by using 137Cs radioactive source have been measured by employing narrow beam transmission geometry. This was accompanied by theoretical computation of mass attenuation coefficients in the wide photon energy range varying from 1 keV to 100 GeV. It has been found that values of mean free path and tenth value layer decrease whereas, density and effective atomic number increase with the increase of barium oxide content. As compared with barite concrete and commercial shielding glass RS-360, our prepared Bi2O3 - BaO - B2O3 glasses have shown better gamma ray shielding properties. This implies that the prepared glass system is a better gamma ray absorber and it has the potential for use in gamma-ray shielding applications.

3.
Chemosphere ; 219: 607-616, 2019 Mar.
Article in English | MEDLINE | ID: mdl-30554048

ABSTRACT

A comprehensive study of seasonal variation of uranium distribution in groundwater of Amritsar, Gurdaspur and Pathankot districts of Punjab, India and assessment of associated radiological risks, chemical risks and effective radiation dose for different age groups, was conducted to determine its health impact on humans residing in these regions. Physicochemical parameters such as pH, EC, TDS, total hardness and contents of various anions such as carbonates/bicarbonates, chlorides, fluorides, nitrates, sulphates and phosphates in groundwater were also analysed to determine correlation between groundwater chemistry and uranium distribution. The average values of uranium concentration in ground water samples of Amritsar, Gurdaspur and Pathankot districts were found to be 8.6 µg L-1, 4.3 µg L-1 and 3.0 µg L-1, respectively, in pre-monsoon and 8.8 µg L-1, 4.9 µg L-1 and 3.4 µg L-1, respectively, in post-monsoon. The uranium concentration in majority of the ground water samples was found to be below the permissible limit of 30 µg L-1 recommended by World Health Organization (WHO, 2011). In all three districts, TDS, EC and bicarbonates were found to have positive correlation with observed uranium contents in both seasons. The annual effective dose due to ingestion of uranium through drinking water was found to be less than the prescribed limit of 100 µSv y-1 given by WHO (2004). Radiological and chemical toxicity risk assessment of uranium in groundwater was also carried out and found to be within the permissible values of 1.67 × 10-4 and 4.53 µg kg-1 day-1 respectively, recommended by Atomic Energy Regulatory Board (AERB, 2004).


Subject(s)
Groundwater/chemistry , Uranium/analysis , Water Pollutants, Radioactive/analysis , Drinking Water/chemistry , Humans , India , Radiation Dosage , Risk Assessment , Seasons
4.
Appl Radiat Isot ; 127: 73-81, 2017 Sep.
Article in English | MEDLINE | ID: mdl-28528235

ABSTRACT

Thallium activated sodium iodide (NaI(Tl)) detector and multi channel analyzer has been utilized to measure gamma rays emitted by radio nuclides found in soil samples of south-west (SW) region of Punjab state, India where elevated level of uranium of around value of 700µg/l in groundwater has been reported. For comparative study, soil samples were also collected and analyzed from west (W) and north east (NE) regions of the state. Uranium and potassium has been found to be comparatively higher in SW region whereas thorium level is higher in W and NE part of Punjab state. Overall concentration level of naturally occurring radio nuclides 40K, 238U and 232Th has been found to be varied from 260.1±17.3 to 728.2±27.7, BDL to 41.9±10.3 and 29.5±7.1 to 88.1±6.2Bq/Kg respectively. Overall average level of 40K and 232Th has been found to be higher as compared to world's average concentration level. Average radium equivalent activity (134.8±23.03 (σ) Bq/Kg), dose rate (61.9±10.3nGy/h), outdoor and indoor dose (0.30±0.05 and 0.08±0.01 mSv/year), external and internal hazard index (0.36±0.06 and 0.42±0.08) has been calculated.

5.
J Environ Radioact ; 167: 110-116, 2017 Feb.
Article in English | MEDLINE | ID: mdl-27914776

ABSTRACT

A survey was conducted to estimate equilibrium factor and unattached fractions of radon and thoron in different regions of Punjab state, India. Pin hole based twin cup dosimeters and direct progeny sensor techniques have been utilized for estimation of concentration level of radon, thoron and their progenies. Equilibrium factor calculated from radon, thoron and their progenies concentration has been found to vary from 0.15 to 0.80 and 0.008 to 0.101 with an average value of 0.44 and 0.036 for radon and thoron respectively. Equilibrium factor for radon has found to be highest in winter season and lowest in summer season whereas for thoron highest value is observed in winter and rainy season and lowest in summer. Unattached fractions of radon and thoron have been found to vary from 0.022 to 0.205 and 0.013 to 0.212 with an average value of 0.099 and 0.071 respectively. Unattached fractions have found to be highest in winter season and lowest in rainy and summer season.


Subject(s)
Air Pollutants, Radioactive/analysis , Air Pollution, Indoor/statistics & numerical data , Radiation Monitoring , Radon/analysis , Air Pollution, Indoor/analysis , India , Seasons
6.
J Environ Manage ; 171: 35-41, 2016 Apr 15.
Article in English | MEDLINE | ID: mdl-26874612

ABSTRACT

A three dimensional semi-empirical model deduced from the existing 1-D model has been used to predict indoor radon concentration with theoretical calculations. Since the major contributor of radon concentration in indoors originates from building materials used in construction of walls and floor which are mostly derived from soil. In this study different building materials have been analyzed for radon exhalation, diffusion length along with physical dimensions of observation area to calculate indoor radon concentration. Also calculated values have been validated by comparing with experimental measurements. The study has been carried out in the mud, brick and cement houses constructed from materials available locally in South-East region of Haryana. This region is also known for its protruding land structure consisting volcanic, felsite and granitic rocks in plane. Further, exhalation (Jw) ratio from wall and floor comparison has been plotted for each selected village dwelling to identify the high radon emanating source (building material) from the study region. All those measured factors might be useful in building construction code development and selection of material to be used in construction.


Subject(s)
Air Pollutants, Radioactive/analysis , Air Pollution, Indoor/analysis , Construction Materials , Models, Theoretical , Radon/analysis , Diffusion , India , Soil
7.
Radiat Prot Dosimetry ; 168(4): 553-60, 2016 Mar.
Article in English | MEDLINE | ID: mdl-26184660

ABSTRACT

A follow-up study was taken up in a mineralised zone situated in Hamirpur district, Himachal Pradesh, India, to investigate high values of radon concentrations reported in past studies as well to update the old radon data based on bare SSNTD technique. In the present investigation, the concentrations of indoor radon, thoron and their decay products have been measured using the newly developed radon/thoron discriminating diffusion chamber with single entry face, direct radon and thoron progeny sensors (DRPS/DTPS), respectively. The measurements have been carried out in 75 dwellings of 14 different villages where the previous studies were carried out using bare SSNTD technique. It was observed that high values of earlier reported radon concentrations were mainly due to thoron interference in the Solid State Nuclear Track Detector (LR-115 type II) exposed in bare mode. Now, the average concentration values and the estimated annual inhalation dose in these villages have been found to be within the reference level as recommended by the ICRP. The annual average indoor radon and thoron concentrations observed in these dwellings have been found to vary from 44±12 to 157±73 Bq m(-3) and 44±11 to 240±125 Bq m(-3), respectively. The equilibrium equivalent concentrations of radon and thoron decay products have been observed to be in the range of 10 to 63 and 1 to 5 Bq m(-3), respectively.


Subject(s)
Air Pollutants, Radioactive/analysis , Air Pollution, Indoor/analysis , Minerals/chemistry , Radiation Monitoring/methods , Radiometry/methods , Radon/analysis , Follow-Up Studies , Housing , Humans , India , Seasons
8.
J Radiol Prot ; 30(1): 63-71, 2010 Mar.
Article in English | MEDLINE | ID: mdl-20220213

ABSTRACT

Radon is a radioactive gas which makes the primary contribution to the natural radiation to which people are exposed. For that reason, great importance is attributed to the determination of radon concentration levels in water, indoor air and soil gas and outdoors. In this paper, measurements of radon concentration in soil gas have been carried out around some areas of the Upper Siwaliks of the Kala Amb, Nahan and Morni Hills, India, using a portable AlphaGUARD PQ 2000 device into which the soil gas is drawn using active pumping. The soil gas radon concentration around the Upper Siwaliks was found to vary from 11.5 +/- 0.9 to 78.47 +/- 3.1 kBq m(-3). The annual average indoor radon concentration in the study area was measured in the range from 71.7 +/- 21.0 to 421.7 +/- 33.6 Bq m( - 3) using LR-115 type II cellulose nitrate films in the bare mode. The values of soil gas radon concentration in the study area were compared with those from the adjoining low-radioactive areas of Punjab. Since the soil or bedrock beneath a building is one of the sources of radon gas in the indoor air, an effort has been made to find a possible correlation between soil gas radon with the indoor radon. A satisfactory positive correlation has been observed between soil gas radon and indoor radon in the study area.


Subject(s)
Air Pollutants, Radioactive/analysis , Air Pollution, Indoor/analysis , Radiation Monitoring/instrumentation , Radon/analysis , Soil Pollutants, Radioactive/analysis , Equipment Design , India
9.
J Environ Radioact ; 100(1): 94-8, 2009 Jan.
Article in English | MEDLINE | ID: mdl-19013694

ABSTRACT

Natural radioactive materials under certain conditions can reach hazardous radiological levels. So, it becomes necessary to study the natural radioactivity levels in soil to assess the dose for the population in order to know the health risks and to have a baseline for future changes in the environmental radioactivity due to human activities. The natural radionuclide (226Ra, 232Th, and 40K) contents in soil were determined for 26 locations around the Upper Siwaliks of Kala Amb, Nahan and Morni Hills, Northern India, using high-resolution gamma-ray spectrometric analysis. It was observed that the concentration of natural radionuclides viz., 226Ra, 232Th and 40K, in the soil varies from 28.3+/-0.5 to 81.0+/-1.7Bqkg(-1), 61.2+/-1.3 to 140.3+/-2.6Bqkg(-1) and 363.4+/-4.9 to 1002.2+/-11.2Bqkg(-1) respectively. The total absorbed dose rate calculated from activity concentration of 226Ra, 232Th and 40K ranged from 71.1 to 162.0nGyh(-1). The radium equivalent (Req) and the external hazard index (Hex), which resulted from the natural radionuclides in soil, were also calculated and found to vary from 149.4 to 351.8Bqkg(-1)and from 0.40 to 0.95 respectively. These values in Upper Siwaliks area were compared with that from the adjoining areas of Punjab. The radium equivalent activities in all the soil samples were lower than the limit (370Bqkg(-1)) set in the Organization for Economic Cooperation and Development (OECD) report and the dose equivalent was within the safe limit of 1mSvy(-1).


Subject(s)
Background Radiation , Environmental Monitoring/methods , Gamma Rays , Soil/analysis , Spectrometry, Gamma/methods , India
10.
Environ Monit Assess ; 154(1-4): 15-22, 2009 Jul.
Article in English | MEDLINE | ID: mdl-18566903

ABSTRACT

Uranium and radon concentration was assessed in water samples taken from hand pumps, natural sources and wells collected from some areas of Upper Siwaliks, Northern India. Fission track registration technique was used to estimate the uranium content of water samples. The uranium concentration in water samples was found to vary from 1.08 +/- 0.03 to 19.68 +/- 0.12 microg l(-1). These values were compared with safe limit values recommended for drinking water. Most of the water samples were found to have uranium concentration below the safe limit of 15 microg l(-1) (WHO, World Health Organization, Guidelines for drinking-water quality (3rd ed.). Geneva, Switzerland: WHO, 2004). The radon estimation in these water samples was made using alpha-scintillometry to study its correlation with uranium. The radon concentration in these samples was found to vary from 0.87 +/- 0.29 to 32.10 +/- 1.79 Bq l(-1). The recorded values of radon concentration were within the recommended safe limit of 4 to 40 Bq l(-1) (UNSCEAR, United Nations Scientific Committee on the Effects of Atomic Radiations, Sources and effects of ionizing radiation. New York: United Nations, 1993). No direct correlation was found between uranium concentration and radon concentration in water samples belonging to Upper Siwaliks. The values of uranium and radon concentration in water were compared with that from the adjoining areas of Punjab state, India.


Subject(s)
Fresh Water/chemistry , Radon/analysis , Uranium/analysis , Water Pollutants, Radioactive/analysis , Water Supply/analysis , Environmental Monitoring
11.
Radiat Prot Dosimetry ; 130(2): 257-63, 2008.
Article in English | MEDLINE | ID: mdl-18245791

ABSTRACT

The indoor radon concentration levels and their regional variations pattern, for two consecutive half-year periods, in a wide range of dwellings of some regions of Punjab and Haryana states have been studied. The objective was to find the relation between the variations of indoor radon levels with the sub-soil and local geology, type of building materials utilised in the dwellings of the region. Keeping this in view, indoor radon measurements have been carried out in the dwellings of 30 villages around the Tusham Ring Complex, Bhiwani district, Haryana, known to be composed of acidic volcanics and associated granites, along with 11 villages of Amritsar District, Punjab. The indoor radon concentration in the dwellings around Tusham (Haryana) was found to vary from 120 +/- 95 to 915 +/- 233 Bq m(-3), whereas radon levels varied from 60 +/- 37 to 235 +/- 96 Bq m(-3) for the dwellings studied in Punjab. We believe that local geology including embedded granitic rocks, and sub-soil, as well as building materials having higher radioactive content, is the major contributor for the higher indoor radon levels observed particularly in the dwelling around Tusham Ring complex, where some dwellings are showing higher radon concentrations than the ICRP recommendations. The environmental samples from some areas of Punjab state and around the Tusham Ring Complex of Haryana state have also been analysed for radon exhalation studies. Higher values for radon exhalation rates have been observed for the Tusham's soil/rock specimens, as compared with soil samples of the Amritsar region of Punjab.


Subject(s)
Air Pollutants, Radioactive/analysis , Air Pollution, Indoor/analysis , Housing , Radium/analysis , Radon/analysis , Geography , India
12.
J Environ Monit ; 7(9): 850-5, 2005 Sep.
Article in English | MEDLINE | ID: mdl-16121263

ABSTRACT

Radon, helium and uranium measurements have been carried out in hot water springs in the Parbati and Beas valleys of Himachal Himalaya. Most of these hot springs are known as famous pilgrimage centers. The activity of dissolved radon in the liquid phase is found to vary widely, by an order of magnitude, between 10 and 750 Bq L(-1), whereas, the dissolved helium content in these thermal springs varies between 10 and 100 ppm. The uranium contents are low and vary from <0.01 to 5 microg L(-1). The measured values of radon, helium and uranium are possibly controlled by structural geology, namely the presence of pervious fault systems, and by the lithology of the leached host rocks. Redox-potential geochemical barriers cause the mobilization of uranile ions in solution (UO2+); the most plausible hypothesis is when the conditions are oxidising, confirming the importance of physico-chemical conditions up to the supergenic environment, to control the fluid geochemistry of the U-He-222Rn system. Some evidence is available from both geothermometric considerations and geochemical data which will be reported elsewhere, whereas the present study is focused on U decay series-noble gas geochemistry. The first analysis of collected 3He/4He data is consistent with a crustal signature at the studied thermal springs.


Subject(s)
Helium/analysis , Hot Springs , Radioactive Pollutants/analysis , Radon/analysis , Uranium/analysis , Data Collection , Environmental Monitoring , Geological Phenomena , Geology , Helium/chemistry , India , Noble Gases/analysis , Noble Gases/chemistry , Oxidation-Reduction , Radon/chemistry , Uranium/chemistry
13.
J Environ Monit ; 5(1): 122-5, 2003 Feb.
Article in English | MEDLINE | ID: mdl-12619766

ABSTRACT

Radon measurements have been carried out in groundwater of Himachal Pradesh and Punjab states, India. Radon concentration values in potable water show a wide range of variation from source to source and from place to place. Generally, radon concentration values in thermal springs groundwater have been found to be higher than the values from other sources.


Subject(s)
Radon/analysis , Water Supply , Environmental Monitoring , India , Soil
14.
J Med Chem ; 29(11): 2136-41, 1986 Nov.
Article in English | MEDLINE | ID: mdl-3023609

ABSTRACT

N-Allyl-, N-(cyclopropylmethyl)-, and N-propyl-endo-ethenotetrahydronororipavines (N-substituted 6,14-endo-etheno-4,5-epoxy-3-hydroxy-6-methoxymorphinans) were synthesized with potential acylating or alkylating moieties at the C-7 position (isothiocyanato, (bromoacetyl)amino, and (methoxyfumaroyl)amino) and examined in vivo for their narcotic agonist and antagonist activities and for their ability to interact with opioid receptors in vitro. The N-(cyclopropylmethyl)-substituted compounds were found to have the highest affinity for opioid receptors among these N-substituted compounds, although all of them were found to be reasonably potent narcotic antagonists in the mouse tail flick vs. morphine assay. Their in vivo potency ranged from 1/8 to 4 times that of nalorphine on intravenous injection in mice. Rat brain membrane binding studies indicated that the compounds interacted with opioid receptors with potencies that ranged from 0.5 times that of morphine (8c, 9c, and 10c) to 0.017 that of morphine (8b). Among the compounds studied here, only the previously reported isothiocyanato compound (10c) and (methoxyfumaroyl)amino compound (8c) interacted irreversibly and selectively with mu or delta opioid receptors, respectively, in assays using NG108-15 neuroblastoma-glioma hybrid cells and/or in a rat brain membrane preparation. Both 8c and 10c were found to interact irreversibly, to a limited extent, with kappa opioid sites in rat brain membranes in which the mu and delta opioid receptors were depleted by interaction with the mu-selective irreversible ligand BIT and the delta-selective irreversible ligand FIT. Neither compound showed irreversible actions in the electrically stimulated mouse vas deferens preparation.


Subject(s)
Enkephalin, Leucine/analogs & derivatives , Isothiocyanates , Narcotic Antagonists/chemical synthesis , Thebaine/analogs & derivatives , Animals , Brain/metabolism , Fentanyl/analogs & derivatives , Fentanyl/pharmacology , In Vitro Techniques , Ligands , Male , Mice , Mice, Inbred ICR , Narcotic Antagonists/metabolism , Narcotic Antagonists/pharmacology , Oligopeptides/pharmacology , Rats , Receptors, Opioid/drug effects , Receptors, Opioid, delta , Receptors, Opioid, mu , Structure-Activity Relationship , Thiocyanates/pharmacology
15.
J Med Chem ; 27(12): 1570-4, 1984 Dec.
Article in English | MEDLINE | ID: mdl-6150112

ABSTRACT

Syntheses of affinity reagents for opiate receptors based on the fentanyl, endo-ethenotetrahydrooripavine, and etonitazene carbon-nitrogen skeletons are described. The isothiocyanate, bromoacetamido, and methylfumaramido alkylating functions were employed in these compounds, some of which had previously been shown to be mu specific (12, BIT) and delta specific (8, FIT and 19, FAO) in vitro. Antinociceptive activity of the title compounds was determined in the mouse hot-plate test, which revealed that certain compounds in each class showed morphine-like activity. The binding EC50 values against [3H]Dalamid for opiate receptors in NG108-15 (delta receptors) and rat brain membranes (mu + delta receptors) are also reported. With this type of experiment, it was possible to independently measure the apparent affinity of the etonitazene congeners 12-14 for the mu and delta receptors.


Subject(s)
Ligands/metabolism , Narcotic Antagonists/chemical synthesis , Receptors, Opioid/metabolism , Animals , Benzimidazoles/analogs & derivatives , Benzimidazoles/metabolism , Benzimidazoles/pharmacology , Cell Line , Cell Membrane/metabolism , Chemical Phenomena , Chemistry , Drug Evaluation, Preclinical , Fentanyl/analogs & derivatives , Fentanyl/metabolism , Fentanyl/pharmacology , Glioma/metabolism , Hybrid Cells/metabolism , Indicators and Reagents , Ligands/pharmacology , Magnetic Resonance Spectroscopy , Mass Spectrometry , Mice , Neuroblastoma/metabolism , Rats , Receptors, Opioid/drug effects , Receptors, Opioid, delta , Receptors, Opioid, mu , Structure-Activity Relationship , Thebaine/analogs & derivatives , Thebaine/metabolism , Thebaine/pharmacology
16.
J Med Chem ; 26(4): 486-92, 1983 Apr.
Article in English | MEDLINE | ID: mdl-6682146

ABSTRACT

Four naturally occurring analogues of forskolin were isolated. Forty-nine semisynthetic derivatives were prepared, incorporating structural alterations at the 1-, 6-, 7-, 9-, 11-, and 14/15-positions. Blood pressure lowering properties of 53 compounds were assessed in anesthetized normotensive cats and of 31 compounds in conscious spontaneously hypertensive (SH) rats. The positive inotropic properties of 25 compounds were investigated in an isolated guinea pig atrial preparation. Forskolin was unique among the compounds in its hypotensive activity in cats and in its positive inotropic properties. Although several derivatives displayed oral antihypertensive activity in the SH rats, none was significantly more potent than forskolin. The optimal structural requirements for activity are apparent, since they are found in forskolin itself.


Subject(s)
Antihypertensive Agents , Cardiotonic Agents , Diterpenes/pharmacology , Animals , Blood Pressure/drug effects , Cats , Colforsin , Dogs , Guinea Pigs , Myocardial Contraction/drug effects , Rats , Stimulation, Chemical , Structure-Activity Relationship
17.
Science ; 220(4594): 314-6, 1983 Apr 15.
Article in English | MEDLINE | ID: mdl-6132444

ABSTRACT

Alkylating agents that display strong selectivity for opiate receptor types delta or mu were prepared by appropriate modification of the structures of the strong analgesics fentanyl, etonitazene, and endoethenotetrahydrooripavine. The availability of these substances should facilitate studies of the structural basis of receptor specificity and of the physiologic roles of these receptors.


Subject(s)
Isothiocyanates , Receptors, Opioid/metabolism , Alkylation , Animals , Benzimidazoles/analogs & derivatives , Benzimidazoles/metabolism , Brain/physiology , Cells, Cultured , Chemical Phenomena , Chemistry , Enkephalin, Methionine/analogs & derivatives , Enkephalin, Methionine/metabolism , Fentanyl/analogs & derivatives , Fentanyl/metabolism , Ligands , Rats , Receptors, Opioid/physiology , Thebaine/analogs & derivatives , Thebaine/pharmacology
18.
Life Sci ; 33 Suppl 1: 159-62, 1983.
Article in English | MEDLINE | ID: mdl-6319854

ABSTRACT

Nine new compounds have been synthesized as potential affinity ligands for specific opioid receptors. The biochemical properties of three of these compounds were examined in detail and one of them, N-cyclopropylmethyl-7 alpha-methylfumaroylamido-6, 14-endoethenotetrahydronororipavine (NIH 10236), was found to be a potent irreversible ligand for the delta opioid receptor. It had the properties of a narcotic antagonist, as determined by its effect on adenylate cyclase activity of NG108-15 neuroblastoma-glioma cell homogenates. It is, thus, the first delta specific alkylating ligand known which is a narcotic antagonist. A second compound, the N-cyclopropylmethyl-7 alpha-isothiocyanato-6, 14-endoethenotetrahydronororipavine (NIH 10235) was found to be a mu specific alkylating ligand in brain and a reversible antagonist in the NG108-15 cells.


Subject(s)
Morphinans/pharmacology , Receptors, Opioid/metabolism , Thebaine/analogs & derivatives , Animals , Binding, Competitive , Brain/metabolism , Cell Line , Cell Membrane/metabolism , Glioma/metabolism , Hybrid Cells/metabolism , Ligands , Mice , Neuroblastoma/metabolism , Rats , Receptors, Opioid/drug effects
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