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Biomedical subjects

B A Rattner

Publications and source records attributed to B A Rattner.

At least 37 records · Page 2Linked to original sources
PubMed1984

Methyl parathion and fenvalerate toxicity in American kestrels: acute physiological responses and effects of cold.

Physiological and toxicological effects of p.o. methyl parathion (0.375-3.0 mg/kg) or fenvalerate (1000-4000 mg/kg) were examined over a 10-h period in American kestrels (Falco sparverius) maintained in thermoneutral (22 degrees C) and cold (-5 degrees C) environments. Methyl parathion was highly toxic (estimated median lethal dose of 3.08 mg/kg, 95% confidence limits of 2.29-4.14 mg/kg), producing dose-dependent inhibition of brain and plasma cholinesterase activity, hyperglycemia, and elevated plasma corticosterone concentration. Brain and plasma cholinesterase inhibition in excess of 50% was associated with transient but pronounced hypothermia 2 h after intubation, although the magnitude of this response was variable. Fenvalerate, at doses far exceeding those encountered in the environment, caused mild intoxication and elevated plasma alanine amino-transferase activity. Cold intensified methyl parathion toxicity, but did not affect that of fenvalerate. Thus, it would appear that organophosphorus insecticides pose far greater hazard than pyrethroids to raptorial birds.

Acetylcholinesterase↗
PubMed1983

Age-related responses to mild restraint in the rat.

Immature, postpubertal, young adult, and middle-aged rats were lightly restrained for 4 h. Relative to untreated controls, restraint uniformly reduced body weight and plasma luteinizing hormone concentration and elevated plasma corticosterone concentration in all age groups. However, restraint increased activities of plasma alanine and aspartate aminotransferase, creatine phosphokinase, and fructose-diphosphate aldolase in only immature and middle-aged animals. This age-related release of tissue enzymes is hypothesized to reflect enhanced responsiveness to catecholamines in immature rats, and possible ischemia related to diminished vasodilatory activity in middle-aged rats. On the basis of these changes, tolerance to restraint in postpubertal and young adults appears to be slightly greater than that of immature and middle-aged rats.

Aging↗
PubMed1983

Hemorrhagic enteritis in captive American kestrels (Falco sparverius).

Hemorrhagic enteritis and hepatitis of suspected adenovirus etiology were the apparent cause of death of nine captive American kestrels. Cloacal hemorrhage was the only prominent gross lesion: disseminated hepatocellular necrosis, and intranuclear inclusion bodies were evident microscopically. Electron microscopy revealed numerous adenovirus-like particles associated with the hepatic lesions. Attempts to serologically identify the agent were unsuccessful.

Animals↗
PubMed1982

Accumulation of 14C-Naphthalene in the tissues of redhead ducks fed oil-contaminated crayfish.

Crayfish, artificially contaminated with 14C-naphthalene-5% water-soluble fraction of No. 2 fuel oil, were force-fed to one-year-old redhead ducks to determine the accumulation of petroleum hydrocarbons. The relative distribution of carbon-14 activity in the gall bladder containing bile, and fat were similar, and significantly greater (P less than 0.05) than the activity in the blood, brain, liver, and kidney. There was a significant increase (P less than 0.05) in the disintegrations per minute per gram (dpm/g) in the blood, brain, kidney, and liver between days 1 and 3 of feeding, indicating a progressive accumulation of carbon-14 activity (naphthalene and presumably its metabolites). There was no significant effect of sex or the interaction of the duration of feeding and sex on carbon-14 activity in any of the tissues. The low daily dose of petroleum hydrocarbons (a total of approximately 1.25 mg/day) received by the ducks from the crayfish and the relatively short feeding regimen did not cause any overt signs of toxicity in the ducks.

Animal Feed↗
PubMed1982

Oviposition and the plasma concentrations of LH, progesterone and corticosterone in bobwhite quail (Colinus virginianus) fed parathion.

Bobwhite quail were fed concentrations of parathion (0,50, 100, 200 or 400 p.p.m.) for 10 days. Food intake, body weight change, brain acetylcholinesterase activity, egg production, and ovary weight were reduced in a dose-dependent manner. In a second experiment, birds were fed 0, 25 or 100 p.p.m. parathion or pair-fed control food to equate consumption in the 100 p.p.m. group. Egg production was not affected in birds fed 25 p.p.m. or in the pair-fed group, but the daily time of oviposition was more variable than in the control group. Cessation of egg production, inhibition of follicular development, and reduced plasma LH concentration were observed in birds fed 100 p.p.m. parathion. These findings indicate that exposure to parathion can impair reproduction, possibly by altering gonadotrophin secretion.

Acetylcholinesterase↗
PubMed1981

Tolerance of adult mallards to subacute ingestion of crude petroleum oil.

Adult male mallards were fed untreated mash or mash containing 1.5% Prudhoe Bay crude oil for 7 days ad lib. During the initial 24 h of exposure to crude petroleum oil, ducks consumed less mash (P less than 0.05) and lost approx. 3.5% of their initial body weight (P less than 0.05), however, neither intake nor body weight differ between groups on days 2-7. Plasma samples collected between 09.00 and 10.00 h on days 0, 1, 3, or 7 indicated that corticosterone, glucose, thyroxine, total protein, and uric acid concentrations, and the activities of aspartate aminotransferase (AST), alanine aminotransferase (ALT), and butyrylcholinesterase (BCHE) were not affected by treatment. These findings suggest that adult mallards may be able to tolerate large quantities of crude petroleum oil mixed in their diet (approx. 25 ml over a 7-day period) without overt or biochemical indications of distress.

Animals↗
PubMed1981

Age and altitude tolerance in rats: temperature, plasma enzymes, and corticosterone.

Tolerance to a 4-h altitude exposure (6,096-8,230 m) was determined in immature, young, and old male rats. The critical survival thresholds were 8,230 m for immature rats and 7,620 m for young and old rats. Hypothermia in immature rats was directly related to hypoxic severity. Body weight loss, elevated plasma corticosterone concentration, and a mean body temperature of 32.5 degrees C were characteristics of immature rats that survived at the critical threshold. Body temperature, weight change, and plasma corticosterone concentration were similar at all altitudes in young adult and old rats. Plasma enzyme activities were relatively unchanged in immature rats, but aspartate aminotransferase (EC 2.6.1.1) and lactate dehydrogenase (EC 1.1.1.27) activities in old rats, in addition to fructose-diphosphate aldolase (EC 4.1.2.13) activity in young adults, were initially elevated (P less than 0.05) at the critical survival threshold (7,620 m). Body temperature and plasma corticosterone (but not plasma enzyme activities) are important criteria for determining altitude tolerance of immature rats. However, plasma asparatate aminotransferase and lactate dehydrogenase activities are more suitable criteria for assessing tolerance in young adult and old rats.

Aging↗
PubMed1980

Plasma gonadotrophins, prolactin and corticosterone concentrations in male mice exposed to high altitude.

Groups of sexually-naive male NFR/N mice were maintained at sea level or exposed to simulated altitudes of 18 000 ft (5486 m) or 22 000 ft (6705 m) for 1, 3, 7, 14 or 28 days. Plasma LH concentrations were slightly but not significantly depressed after 1 day of hypoxia. Plasma FSH values were reduced (P < 0.05) after 1, 7, 14 and 28 days of exposure to 22 000 ft when compared to the values in the other groups. Prolactin concentrations fluctuated considerably, but were not uniformly affected by high altitude exposure. Exposure to 18 000 ft resulted in an elevation of plasma corticosterone concentration (P < 0.05) for 3 days, which was followed by a decline to control group values, whereas at 22 000 ft corticosterone levels remained elevated. These findings indicate that plasma LH values are transiently reduced during the initial 24 h of exposure to high altitude and that plasma FSH concentrations are depressed in a sustained manner during severe hypoxia.

Altitude↗
PubMed1979

Cross-adaptive effects of cold, hypoxia, or physical training on decompression sickness in mice.

The effects of adaptation to cold, hypoxia, or exercise on hyperbaric decompression tolerance were investigated in two factorial experiments. For either 14 or 28 days, groups of mice were handled (control); exposed discontinuously for 4 h to cold (4 degrees C) or hypoxia (P approximately 379 or 320 Torr); or exercised by swimming (15 min at 31 degrees C) or treadmill excursion (8.1 m/min for 1 or 1.5 h). The animals were divided into subgroups, exposed to one of three hydrostatic pressures (7.6--11.1 ATA) for 30 min, decompressed, and observed to determine survival rate or bends incidence (type II decompression sickness). Decompression sickness was significantly reduced (P less than 0.05) in the treadmill-trained animals, was unchanged in cold-exposed and swim-exercised mice, and tended to increase in animals adapted to hypoxia. Enhanced tolerance by treadmill training is presumably due to lean body conformation, which could reduce nitrogen saturation of tissues, and greater muscle capillarization and cardiovascular fitness, which may improve nitrogen elimination. Reduced tolerance with adaptation to hypoxia may be attributed to rheological changes associated with polycythemia, which facilitate bubble production.

Adaptation, Physiological↗
PubMed1979

Plasma gonadotrophins and progesterone concentrations during various degrees of underfeeding in pregnant mice.

Daily reduction of the normal (ad libitum) food consumption by as little as 35% significantly reduced (P less than 0.05) the percentage of mice with implantation sites at Days 7 and 9 of gestation. Underfeeding decreased body weight and reduced the weight of the ovaries and uterus. Plasma progesterone was decreased (P less than 0.05) as dietary intake was restricted and was associated with regression of the corpora lutea. No significant alterations in the plasma values of LH and FSH were observed in mice underfed between Days 1 and 9 of pregnancy. The decrease in plasma progesterone in the absence of reduced LH values may indicate that progesterone secretion between Days 5 and 9 of gestation is not controlled solely by LH.

Animals↗
PubMed1979

Adrenal function and the incidence of bends after decompression in mice: effect of adrenalectomy, corticosteroids, decompression intensity, and time of day.

The adrenocortical endocrine subsystem has been demonstrated to enhance mammalian tolerance to harsh environmental conditions, including hypoxia and temperature extremes. In a series of factorial experiments, mice were exposed to one of three elevated hydrostatic pressures for 30 min and then decompressed (0.75 atm/s). It was demonstrated that 1) tolerance to decompression does not differ significantly (P greater than 0.3) in surgically intact, sham adrenalectomized, or in adrenalectomized animals; 2) intraperitoneal administration of pharmacologic doses (0.4, 1.0, and 2.0 mg/mouse) or corticosterone or deoxycorticosterone acetate does not significantly enhance (P greater than 0.1) survivorship when compared to vehicle-injected controls; and 3) the incidence of decompression sickness (DS) does not fluctuate with time of day (P greater than 0.4). In a fourth study, the plasma concentration of corticosterone was quantitated in 1) colony control mice, 2) mice exposed to the 1-ATA chamber environment (chamber control), or 3) mice compressed to 3, 5, 7, 9, or 11 ATA and then decompressed. In general, plasma corticosterone in symptom-free mice was elevated approximately threefold (P less than 0.05) by exposure to the 1-ATA chamber environment and by decompression from 3 to 11 ATA. At 11 ATA, plasma corticosterone levels in decompressed mice exhibiting decompression sickness symptoms were significantly elevated (P less than 0.05) compared to the levels observed in decompressed symptom-free mice. These studies indicate that adrenocortical function does not enhance tolerance to decompression in mice.

Adrenal Cortex Hormones↗
PubMed1978

Embryonic implantation, dietary intake, and plasma GH concentration in pregnant mice exposed to hypoxia.

Inseminated mice were: 1) exposed to 8% O2, 2) pair fed to mice exposed to 8% O2, 3) fasted at 21% O2 or 4) maintained at 21% O2 (control) between Days 1-3 of pregnancy. The frequency of embryonic implantation sites in mice was reduced by greater than 60% in 8% O2 exposed and pair fed animals, and by 100% in fasted mice. During the initial 24 h of exposure to 8% O2, a significant component of the body weight lost by hypoxic mice was associated with the reduction in dietary intake. The contragestational effects of hypoxia and fasting were attributed to the endocrine consequences of inanition induced by hypophagia and adypsia. Plasma samples collected at 6-h intervals revealed a significant reduction in GH concentration in treatment groups compared to the controls.

Animals↗