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Showing papers on "Lead acetate published in 1991"


Journal ArticleDOI
TL;DR: Red-tailed hawks were exposed to sublethal levels of lead acetate for periods of 3 or 11 weeks and short term, low level lead exposure did not effect immune function significantly in the hawks, as measured by antibody titers to foreign red blood cells or by the mitogenic stimulation of T-lymphocytes.
Abstract: Red-tailed hawks were exposed to sublethal levels of lead acetate for periods of 3 or 11 weeks. Alterations in the heme biosynthetic pathway were demonstrated after the first week of exposure to 0.82 mg lead per kilogram body weight per day. Activity of erythrocyte porphobilinogen synthase (aminolevulinic acid dehydratase) was depressed significantly and did not return to normal levels until 5 weeks after the termination of lead treatments. A rapid and relatively brief increase in erythrocyte free protoporphyrin and a slower but more prolonged increase in its zinc complex were also demonstrated with exposure to this dose of lead for 3 weeks. Less substantial decreases in hematocrit and hemoglobin levels occurred but only in the longer experiment with exposure to higher lead levels. Short term, low level lead exposure did not effect immune function significantly in the hawks, as measured by antibody titers to foreign red blood cells or by the mitogenic stimulation of T-lymphocytes. Increased lead exposure produced a significant decrease in the mitogenic response but had no effect on antibody titers.

85 citations


Journal ArticleDOI
TL;DR: Serum testosterone and sperm concentration and production rate were significantly suppressed in those animals that were exposed to lead acetate starting at age 52 days and 70 days, but not 42 days, indicating that prepubertal rats may be less sensitive to the toxic effects of lead than are rats whose exposure begins after puberty has been initiated.

69 citations


Journal ArticleDOI
TL;DR: Examination of whole brain neurotransmitters indicated a significant increase in both serotonin and norepinephrine levels but no change in dopamine in response to lead intoxication, as well as a high significance among fish exposed to 1.0 mg/l lead.

59 citations


Journal ArticleDOI
TL;DR: The lead-induced depression of the long-term potentiation might be related to the behavioral deficits observed in chronically lead-exposed mammals.

58 citations


Journal ArticleDOI
TL;DR: It is concluded that lead not only enhances LPS lethality but also TNF liver injury and increases LPS-stimulated serum TNF levels, suggesting that the lead-enhanced LPS model offers a system for studying TNF-induced liver injury.

43 citations


Journal ArticleDOI
TL;DR: No convincing evidence could be found of any deleterious effect of current environmental lead levels on human health and thus the tiny contribution of lead acetate exposure from hair-colouring use can be regarded unequivocally as being toxicologically insignificant.

34 citations


Journal ArticleDOI
TL;DR: It was concluded that lead exposure through drinking water may produce increased arterial blood pressure and minor changes in the myocardium and whether these changes are mediated through the effect of lead on the calcium transport needs further investigation.
Abstract: The rats were exposed to lead (0.25, 0.5 and 1.0 per cent lead acetate through drinking water) for 90 days to study its effect on some physiological and morphological parameters of the cardiovascular system. Blood lead levels increased in a dose dependent manner but heart tissue showed rise at only two higher doses in exposed animals. the two higher doses of lead resulted in an increased arterial blood pressure and calcium influx in atrial trabeculae and papillary muscles. No marked pathological or histochemical changes were observed in heart tissue excepting congestion and slightly reduced activity of succinic dehydrogenase in the highest dosed group. It was concluded that lead exposure through drinking water may produce increased arterial blood pressure and Minor changes in the myocardium. Whether these changes are mediated through the effect of lead on the calcium transport needs further investigation.

29 citations


Journal ArticleDOI
TL;DR: Lead administration reduced the ability of the phase II reaction of drug metabolism, although glutathione depletion was not necessarily a critical factor for impairmen of GST per se.

26 citations


Journal ArticleDOI
TL;DR: It is suggested that the lead line results from a direct effect of lead on the odontoblasts and other hard tissue-forming cells producing a rapid loss of intracellular calcium temporarily displaced by lead ions and a subsequent disturbance of local calcium metabolism.

26 citations


Journal ArticleDOI
TL;DR: Oral lead administration to weaning male rats for 70 days resulted in the marked accumulation of this metal in blood and testicular tissue, and changes in the Sertoli cells may lead to changes in spermatogenesis after chronic exposure.
Abstract: Summary Oral lead administration (250 ppm lead acetate through drinking water) to weaning male rats for 70 days resulted in the marked accumulation of this metal in blood and testicular tissue. No marked changes were evident in light microscopy. Ultrastructural changes were revealed in the form of vacuolisation of Sertoli cell cytoplasm and increase in the number and size of lysosomes. Some of the vacuoles contained vesicle like structures. Although there was no impairment of spermatogenesis, the changes in the Sertoli cells may lead to changes in spermatogenesis after chronic exposure.

22 citations


Journal ArticleDOI
01 Jan 1991-Glia
TL;DR: The intensity of the astroglial response was enhanced after 90 days of lead intoxication, showing an increment of GFAP immunoreactivity, which is consistent with the ultrastructural alterations.
Abstract: The present study was performed in order to follow the response of astroglial cells in the rat hippocampus to chronic low-level lead exposure. The experiments combined immunohistochemistry using anti-glial fibrillary acidic protein (GFAP) antibody and conventional transmission electron microscopy (EM). Chronic administration with drinking water [1 g% w/v (subclinical dose) of lead acetate dissolved in distilled water] was started through the mother's milk when pups were 7 days old. Following weaning, experimental offspring were treated for 3 months with the same concentration of adulterated water. The group of intoxicated animals and their controls were sacrificed by perfusion-fixation at 30, 60, and 90 days of exposure. After 60 days of lead treatment, staining of GFAP-positive cells demonstrated an astroglial transformation from the quiescent to the reactive state, characterized by an increase in GFAP. In control rats no changes in GFAP immunostaining were observed. The intensity of the astroglial response was enhanced after 90 days of lead intoxication, showing an increment of GFAP immunoreactivity. Quantification of these changes was made by computerized image analysis, confirming that the sectional areas of the astroglia in lead-exposed animals were larger than those in controls. These results are consistent with the ultrastructural alterations. Simultaneously with the increment in gliofilaments, intranuclear inclusions were seen in some astrocytes. The mechanisms by which lead affects astrocytes are unknown. Probably the astroglial changes induced by lead intoxication produce microenvironmental modifications that may disturb the neuronal function.

Journal ArticleDOI
TL;DR: Existence of deaths among fishes reared in water contaminated with the inorganic pollutants (PbCl2 and AlCl3) but not with the organic lead is confirmed.
Abstract: To study the effect of contaminated rearing water of catfish (Clarias lazera) with lead acetate, lead chloride or aluminum chloride, 3 level of concentrations (10, 50 and 100 ppm) of each salt were added in the rearing water for 6 weeks The results of this experiment confirmed the followings: Existence of deaths among fishes reared in water contaminated with the inorganic pollutants (PbCl2 and AlCl3) but not with the organic lead The treatments led to pathological findings eg haemorrhages and congestion of the gastrointestinal tract and kidneys Protein content was decreased insignificantly (P greater than or equal to 005) than for the control The decrease was accompanied with the elevation of contamination level, especially in the lead acetate treatment The ether extract increased in the treated fish than in the control The increase was related to the pollutant level especially in the PbCl2 and AlCl3 treatments (P less than or equal to 001) Gross energy, generally, increased slightly by the application of the pollutants than in the control fishes Muscular contents of ash, calcium, magnesium, and lead were increased significantly than the control The contents of Na, K (P less than or equal to 001) and P (P less than or equal to 005) decreased in the treated fishes

Journal Article
TL;DR: The results indicate a specific stress reaction in female rats, and in males only the sympathico-adrenal system seems to be affected by such lead exposure.
Abstract: Effects of a three-month exposure of both male and female rats under their development to lead acetate in drinking water on the hypothalamus-pituitary gland-thyroid gland-suprarenals and sympathico-adrenal systems were evaluated by determining noradrenaline (NA) in the hypothalamus and striatum, thyroxine (T4), 3,5,3'-tri-iodothyronine (T3) and corticosterone (CS) in the serum and catecholamines (CA) in both blood and suprarenals NA in the hypothalamus and striatum was decreased in exposed males CA in blood and suprarenals and CS in the serum were increased and NA decreased in the hypothalamus and striatum in exposed females No serum T3 and T4 changes were found in males or females The exposure to lead resulted in increased weight of spleen and kidneys in both sexes and suprarenals in females only Weights of hypothalamus, striatum, liver and thyroid gland did not change Female rats exposed to lead grew more slowly than control animals Retardation in the growth was not statistically significant in males The results indicate a specific stress reaction in female rats In males only the sympathico-adrenal system seems to be affected by such lead exposure

Journal Article
TL;DR: Tetrabutyl lead was present in tissues in the highest quantities and lead acetate was the most poorly absorbed with the exception of lead oxide which demonstrated no absorption.
Abstract: Diffusion tubes were used to measure the degree of in vitro penetration of tetrabutyl lead, lead naphthanate, lead nuolate, lead acetate and lead oxide in excised guinea pig skin and human skin from autopsy. Tetrabutyl lead demonstrated the greatest penetration in skin from both guinea pig and man. Lead nuolate, lead naphthanate and lead acetate followed in descending order in the human tissue. A similar pattern occurred with guinea pig skin in most cases. There were no measurable amounts of lead oxide absorbed in either species. In vivo absorption was measured by applying 300 mg/kg tetrabutyl lead, lead nuolate, lead naphthanate or lead oxide to the shaved backs of guinea pigs for 7 d under occluded wrappings. Tetrabutyl lead was present in tissues in the highest quantities. Lead nuolate was present in greater amounts than lead naphthanate in the liver and kidneys. Lead acetate was the most poorly absorbed with the exception of lead oxide which demonstrated no absorption.

Journal ArticleDOI
TL;DR: The highest dose of lead administration and iron deficiency exhibited more lead accumulation in maternal blood, placentae, and fetuses, and maximum pathologic changes in the fetal kidney when compared with the other doses and also with the fetuses of dams not deficient in iron.

Journal ArticleDOI
TL;DR: The effectiveness of alpha-mercapto-beta-(2-furyl)acrylic acid (MFA) and N-benzyl-N-dithiocarboxy-D-glucamine (NaB) in the mobilization and excretion of lead was investigated in rats as discussed by the authors.

Journal Article
TL;DR: The results suggest a nonspecific stress reaction in rats activating hypothalamo-pituitary-thyroid-adrenal axis, and significant changes of all hormones, liver, spleen and kidney weight were observed in rats given 2% lead acetate.
Abstract: Male Wistar rats were given 0.5% lead acetate and natrium acetate equimolar to 2% lead acetate for 3 months, 1 and 2% lead acetate for 2 months. Noradrenaline (NA) in hypothalamus and striatum corticosterone, thyroxine and 3,5,3'-triiodothyronine in serum and catecholamines (CA) in adrenals were determined at one month's interval. Results were accomplished by body and organ weights. All the changes depend on lead exposure level and time of exposure. At the three doses, lead exposure produced a significant decrease of NA in hypothalamus and striatum, increase of CA in adrenals and increase of kidney weight. Significant changes of all hormones, liver, spleen and kidney weight were observed in rats given 2% lead acetate. The stress effects of acetate was excluded by the lack of biochemical, organ or body weight effects of sodium acetate. Our results suggest a nonspecific stress reaction in rats activating hypothalamo-pituitary-thyroid-adrenal axis.

Journal ArticleDOI
TL;DR: Thiamin, CaEDTA and the combined treatments decreased the absorption of lead- 203 and the biological half-life of retained lead-203 following oral or intraperitoneal lead exposure and may have therapeutic application for the treatment of lead poisoning.

Journal ArticleDOI
TL;DR: Intraperitoneal administration of lead acetate to male Sprague-Dawley rats resulted in the tissue-specific transcriptional activation of the microsomal epoxide hydrolase gene in kidney, which was followed by a 15-fold increase in the level of kidney epoxidehydrolase mRNA, while no change in mRNA level was noted in liver.

Journal Article
TL;DR: The results suggest a non-specific stress response in female rats and in male rats only the sympatho-adrenal system seems to be affected by this lead exposure.
Abstract: The effect of 5 months' exposure to 05% lead acetate in drinking water on the hypothalamo-pituitary-thyroid-adrenal system was evaluated by measuring hypothalamic and striatic noradrenaline (NA), serum thyroxine (T4), 3,5,3'-triiodothyronine (T3) and corticosterone (CS) and blood and adrenal catecholamines (CA) levels in developing rats of both sexes Blood CA were increased and hypothalamic and striatic NA was decreased by exposure in male rats In female rats, blood and adrenal CA and serum CS were increased and hypothalamic and striatic NA was decreased by exposure No changes in the two sexes were observed in serum T3 and T4 Exposure induced an increase in spleen and kidney weights in both sexes; the weight of liver was increased only in female rats Weights of hypothalamus, striatum, adrenals and thyroid glands were not changed Female but not male rats exposed to lead gained less weight than controls The results suggest a non-specific stress response in female rats In male rats only the sympatho-adrenal system seems to be affected by this lead exposure

Journal ArticleDOI
TL;DR: It was found that a single intraperitoneal administration of lead at dose 150 mg Pb/kg b.w. led to ultrastructural changes in the neutrophils at 3 and 6 h post injection, which were most clearly expressed 6 h after lead administration.
Abstract: Summary The influence of lead acetate on the ultrastructure of peripheral neutrophils was investigated in adult male rats. It was found that a single intraperitoneal administration of lead at dose 150 mg Pb/kg b.w. led to ultrastructural changes in the neutrophils at 3 and 6 h post injection. At the time of testing the exposed population had a mean (± SD) blood lead concentration from 206.2 ± 24.8 µg/100 ml to 75.2 ± 9.9 µg/100 ml compared with a mean value of 4.0 ± 0.7 µg/100 ml for the control groups. The ultrastructural alterations such as irregular nuclei with deep invaginations, plasma membrane pockets, the presence of vacuoles with a heterogeneous material and an increasing amount of RER cisternae, were most clearly expressed 6 h after lead administration. In addition there appeared sometimes nuclear pockets, and a prominent crystalline inclusion placed in the cytoplasmic matrix of some neutrophils. No differences in the mitochondrial morphology and cytoplasmic granule pattern between exposed and control rats were observed.


Journal ArticleDOI
TL;DR: It is concluded that combined exposure to lead acetate and disulfiram during development induces regionally specific changes in GFA-immunoreactive astrocyte morphology, which demonstrates the usefulness of smear preparations combined with computerized image analysis to study the morphology of G FA-IMmunore Active Astrocytes as an index of toxic effects in CNS.

Journal ArticleDOI
TL;DR: Although gastrointestinal dysfunction is often associated with clinical cases of acute lead toxicity, chronic exposure to these low levels of lead acetate did not significantly alter gastric motility in red-tailed hawks.
Abstract: In order to determine the effects of low level lead exposure on gastric motility in raptors, strain gage transducers were surgically implanted on the serosal surface of the muscular stomach of three red-tailed hawks. The frequency and amplitude of gastric contractions during ingestion and early digestion were monitored for 1 week under control conditions and for 3 weeks while the birds were fed 0.82 or 1.64 mg lead (as lead acetate) per kg body weight each day. Exposure to these doses did not appreciably affect either the frequency or amplitude of gastric contractions in these birds. This low level lead exposure also had no consistent effect on the regular egestion of pellets of undigested material by hawks. Daily exposure to doses up to 6.55 mg lead/kg body weight did not affect the frequency or timing of pellet egestion, and exposure to 1.64 mg lead/kg did not affect the gastric contractions associated with pellet egestion. Although gastrointestinal dysfunction is often associated with clinical cases of acute lead toxicity, chronic exposure to these low levels of lead acetate did not significantly alter gastric motility in red-tailed hawks.

Journal ArticleDOI
TL;DR: In this article, the extent of absorption of lead (Pb) in mining waste soil from Butte, Montana was investigated using a soil dose response approach, where the test soil dose levels at 2 and 5% were chosen to bracket a pica-for-soil child's soil exposure levels.
Abstract: The purpose of this study was to determine the extent of absorption of lead (Pb) in mining waste soil from Butte, Montana. It is the first study to fully investigate the bioavailability of lead in soils containing mine waste using a soil dose response approach. Young 7–8 week-old male and female Sprague-Dawley rats (5 animals/sex/group) were given mining waste soil [810 ppm lead (Test Soil I) or 3,908 ppm lead (Test Soil III)] mixed in a purified diet (AIN—76™) at four different dose levels (0.2, 0.5, 2 and 5% dietary soil) for 30 consecutive days. The test soil dose levels at 2 and 5% were chosen to bracket a pica-for-soil child's soil exposure levels. A pica-for-soil child is a young child who eats large quantities of soil (10 g day−1). Standard groups included untreated controls and dosed feed soluble lead acetate groups (1, 10, 25, 100 and 250 μg Pb g−1 feed). The concentrations of lead acetate were chosen to bracket the test soil dose levels of lead. Liver, blood and femur, representing the t...

Journal ArticleDOI
TL;DR: A morphometric analysis of Schwann cell cytoplasmic and nuclear areas and their relationship to the cross‐sectional area of the associated myelinated fibre was performed to quantify this cell hypertrophy in lead‐induced neuropathy in the rat.
Abstract: Schwann cell hypertrophy is an early change observed in lead-induced neuropathy in the rat. In order to quantify this cell hypertrophy, a morphometric analysis of Schwann cell cytoplasmic and nuclear areas and their relationship to the cross-sectional area of the associated myelinated fibre was performed. The study was carried out on sural and peroneal nerves from three groups of adult rats. Group I was intoxicated with 4% lead acetate in the drinking water for 6 weeks; group II animals were treated as in group I and then restored to standard laboratory conditions for 30 days; and group III were controls. The results showed that: (a) after 6 weeks of lead exposure, cytoplasmic and nuclear areas were significantly greater in intoxicated, compared with control rats; (b) after 30 days recovery, Schwann cell cytoplasmic and nuclear areas did not differ from control rats.


01 Jun 1991
TL;DR: Results suggested that the functional activity of LCN could be modified by the observed changes, and ultrastructural modifications could be a morphological substrate for the subtle neuropsychological deficits of rats chronically exposed to relatively low concentration of lead.
Abstract: The effect of chronic lead exposure in neonatal rats was examined, particularly on hippocampal local circuit neurons (LCN). Chronic lead was administered to rat pups in the first week of life through the mother milk. During the lactation period the mother only drank water containing 1 g% lead acetate (w/v) -subclinical dose. Following weaning, the young rats were treated for 3 months with the same concentration of lead-adulterated water. Electron microscopy studies were made at 30, 45, 60, 75 and 90 days of age. After 2 months of lead exposure, irregular outline and dark-condensed cytoplasm in non-pyramidal neurons, in basket and in granule cells were found. Within the neuropil, some beaded and smooth dendrites, as well as some axons and synaptic terminals, appeared condensed and darker than the surrounding elements. Coincident with the LCN alterations, astrocytes showed an increment of glial filaments. These results suggested that the functional activity of LCN could be modified by the observed changes. Such ultrastructural modifications could be a morphological substrate for the subtle neuropsychological deficits of rats chronically exposed to relatively low concentration of lead.