Search PubMed⌕ Search

Biomedical subjects

T F Massaro

Publications and source records attributed to T F Massaro.

14 recordsLinked to original sources
PubMed1990

Interactions between lead and essential elements: a review.

Young children are especially susceptible to the toxic effects of lead. Although the effects of overt lead intoxication have been well studied, critical information on the long-term effects of low level lead exposure is lacking. The results of recent clinical studies indicate that "chronic" low level lead exposure during development can result in behavioral alterations in the absence of overt neurotoxicity. The perturbation of central nervous system functioning may be the result of essential mineral deficiencies resulting from lead-induced impairment of mineral availability and/or an increased sensitivity to lead in the absence of adequate levels of essential minerals. This article reviews research undertaken to examine the interactions between calcium, iron, zinc, copper and lead with reference to how this may impact central nervous system functioning.

Animals↗
PubMed1984

A test of the carbon-nitrogen balance technique to measure body composition of exercising animals.

Four randomly selected male Wistar rats were placed in separate metabolic chambers containing torqued Wahmann activity wheels. Quantitative collection of expired CO2, feces, and urine were carried out and the Carbon-Nitrogen balance technique was used to determine the changes in body composition of exercised animals during sequential, 48-hour periods. The behavioral contigency significantly increased running performance and weight gain. The weight of all body compartments, with the exception of body fat, increased significantly. Increased exercise significantly increased heat production. Sufficient data were gathered to permit discussion of individual animals and their adaptations and responses to the running contingencies.

Animals↗
PubMed1984

Multiple dose exposure effects on the tissue distribution of lead in the preweanling rat.

The time dependent tissue/organ distribution of Pb resulting from repeated intragastric exposure of the preweanling rat to Pb acetate was investigated. On the day of parturition, 12 dams were assigned randomly either to control (nonhandled) or Pb-treated groups and their litters were culled to 8 pups. On days 6, 9, 12, 15, and 18 post partum, the experimental groups received 50 mg Pb (as Pb acetate)/kg body weight containing 50 microCi of 210Pb. By day 7 (N = 15), the liver had accumulated 1.48 +/- 0.14 micrograms Pb/g wet weight (avg. +/- SE) and the kidney, 1.21 +/- 0.20 micrograms/g. However, most of the Pb was found in the intestine (129.07 +/- 20.90 micrograms/g) and intestinal contents (8.31 +/- 1.16 total Pb). By day 14 (N = 14), bone had accumulated 20.86 +/- 1.05 micrograms/g Pb while the liver and kidney levels had increased to 2.59 +/- 0.22 and 2.51 +/- 0.08 micrograms/g, respectively. At this time, blood was found to contain 0.87 +/- 0.07 micrograms/g and brain, 0.14 +/- 0.03 micrograms/g. On day 14, the greatest quantities of Pb were again found in the intestine and intestinal contents; 45.87 +/- 4.93 and 441.26 +/- 23.77 micrograms/g, respectively. By day 21 (N = 32), the concentration of Pb in liver, intestine, intestinal contents, and blood had decreased to 1.03 +/- 0.02, 4.22 +/- 1.68, 1.03 +/- 0.02 and 0.29 +/- 0.02 micrograms/g, respectively, while that in kidney remained unchanged (2.38 +/- 0.07 micrograms/g). By day 21, the concentration of Pb in bone and brain increased to 43.85 +/- 1.18 and 0.31 +/- 0.02 micrograms/g, respectively. However, it is to be noted that brain Pb levels were relatively low. There was no accumulation of Pb in lung, heart, stomach, or spleen at any time. Although the spleen did not accumulate any Pb, it was effected by Pb exposure as evidenced by a significant decrease in wet weight. Body weights of Pb-treated animals were comparable to those of control animals throughout the period of preweanling development.

Age Factors↗
PubMed1983

Tissue distribution of lead in the neonatal rat exposed to multiple doses of lead acetate.

The tissue distribution of lead (Pb) was examined in the neonatal rat intragastrically administered lead acetate (50 mg/kg, containing 210Pb) beginning on d 6 postpartum and thereafter at 3-d intervals to d 18. A time-dependent pattern of uptake was observed in bone, kidney, liver, and brain, while stomach, lung, heart, and spleen had no accumulation of Pb. The highest concentration of Pb at d 21 was detected in bone, and the least amount was found in blood and brain. Body weight was not significantly affected by the level of Pb exposure employed.

Animals↗
PubMed1982

Effects of moderate zinc deficiency on cognitive performance in young adult rats.

Two experiments were conducted to establish a dietary zinc level which approximates a moderate deficiency in the young adult rat and to determine if a concurrent zinc deficiency affects cognitive performance. Male rats were fed varying levels of zinc in diet throughout a 17-day period. The lowest dietary level that depressed serum and bone zinc without influencing food consumption or body weight gains was observed to be 5.8 microgram Zn/g diet. Young adult rats maintained on either a zinc adequate (24.4 microgram Zn/g) or low-zinc (5.3 microgram Zn/g) diet were tested in a modified Skinner Box involving tests of visual, auditory, association, and discrimination learning. No differences were observed in the visual discrimination performance of the zinc deficient animals when compared with control counterparts. Deficits in the ability to transfer a learned association between visual and auditory stimuli were observed, however, in the deficient group during the transfer test phase. The latter performed better during the final auditory discrimination task in transferring a learned food-relevant cue.

Animals↗
PubMed1981

The effect of iron deficiency on cognitive performance in the rat.

The effects of iron deficiency anemia on cognitive performance of the rat were examined in a test of transfer learning. Young adult female rats maintained on either an iron-adequate (37 ppm) or low-iron (7 ppm) diet were behaviorally tested in a modified Skinner box. Tests involved visual, auditory, association, and discrimination learning. Circulating hemoglobin levels of anemic animals approximated 58.5 and 64.3% of well-nourished controls during the training and final test phase. Hematocrit levels of anemic animals followed a similar reduction, approximating only 67.0 and 72.1% of iron-adequate controls. No significant differences were observed in visual discrimination performance of the anemic animals when compared to their well-nourished counterparts. Deficits in the ability to transfer a learning association between visual and auditory stimuli were observed, however, in the anemic animals during the final test phase. The results of the present study are indicative that some aspect of association learning is adversely affected by concurrent iron-deficiency anemia.

Acoustic Stimulation↗
PubMed1977

Early protein malnutrition in the rat: behavioral changes during rehabilitation.

Behavioral development was studied in 2 groups of rats during the postweaning period. Pups were selected from litters nursed by dams fed either a standard protein (25% casein by weight) or a low protein diet (12% casein) during lactation. Two pups from each litter were housed together and fed the control diet throughout rehabilitation. Behavioral observations were made by repeated time-lapse photography at 5-day intervals. Differences in home cage behavior were observed at the onset of rehabilitation in the postnatally malnourished rats. Increased feeding behavior was observed during the 1st week of rehabilitation. Locomotor behavior was depressed during the rehabilitation period in the experimental animals. Climbing activity, however, was significantly greater. Self-grooming activity was elevated throughout rehabilitation in post-natally malnourished animals. During the course of rehabilitation, the behavioral differences between the 2 groups gradually disappeared.

Animals↗
PubMed1977

Protein malnutrition induced during gestation: its effect on pup development and maternal behavior.

Repeated time-lapse photographic observations were used to examine the ontogeny of behavioral development in prenatally malnourished rat pups following birth. Pups born to dams receiving a low protein diet (7% casein by weight) were fostered at birth to well-nourished dams and behavioral observations were made at 4-day intervals. Dams nursing gestationally malnourished pups were observed to spend more time in the nesting area with their pups towards the end of lactation. Moreover, the behavioral development (locomotion, feeding, and rearing and climbing activity) of gestationally malnourished offspring was depressed when compared to their controls. The results indicate that prenatal undernutrition alters the behavioral development of the offspring and maternal behavior of the dam in a manner which reduces the exposure of the pup to the immediate environment.

Animals↗
PubMed1975

Maternal malnutrition and the neonatal environment.

Altered behavioral development was observed in suckling rats from dams fed a low protein diet either during gestation or during the lactation period. Lactational malnutrition markedly depressed all behaviors displayed by the suckling young. These included litter fragmentation, pup climbing, rearing, feeding, and drinking behavior. Although less severe, pups from a dam fed a deficient diet during gestation displayed the same altered behavioral development. Moreover, small birth weight pups born from well-nourished dams also showed delayed behavioral development. Contact with pups was increased in dams who were malnourished during the lactation period or who were nursing pups from dams malnourished during the gestation period. Results support in part the hypothesis that malnourished early in life "functionally isolates" the developing animal from its immediate environment.

Animals↗
PubMedDate not supplied

Low-level lead exposure affects latent learning in the rat.

Neonatal rats were administered intragastrically either lead acetate (50 mg Pb/kg-BW) or an equal molar solution of sodium acetate at days 6, 9, 12, 15, and 18 postpartum. At 33 days of age, each animal began a training sequence to develop maze running skills. Animals within each treatment group, i.e., lead exposed (Pb), control vehicle (CV), and control nonhandled (CNH) were assigned randomly to either latent learning or open-field testing groups. The former individually explored a symmetrical maze while satiated; the latter were exposed to an apparatus devoid of barriers. All animals were then food deprived and appetitively tested in the latent learning maze. The Pb, CV, and CNH animals naive to the maze did not differ in maze performance. The CV and CNH animals that previously experienced the maze committed fewer errors than non-experienced counterparts. Pb treated animals showed no evidence of a positive transfer effect of their earlier experience.

Animals↗