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Low level lead and inhibition of erythrocyte pyrimidine nucleotidase

C R Angle1, M S McIntire

  • 1Department of Pediatrics, University of Nebraska Medical Center, Omaha.

Environmental Research
|October 1, 1978
PubMed

Insights

Pyrimidine 5'-nucleotidase (P5N) levels in red blood cells decrease with rising blood lead exposure in children and rats. This enzyme may serve as a sensitive biomarker for early lead poisoning detection.

Area of Science:

  • Biochemistry
  • Toxicology
  • Pediatrics

Background:

  • Lead exposure is a significant public health concern, particularly in young children.
  • Sensitive biomarkers are needed for early detection of lead toxicity.
  • Pyrimidine 5 omino-nucleotidase (P5N) is an enzyme involved in nucleotide metabolism.

Purpose of the Study:

  • To investigate the potential of red blood cell Pyrimidine 5 omino-nucleotidase (P5N) as a sensitive biomarker for low-level lead exposure.
  • To establish the correlation between blood lead levels and P5N activity in both children and rats.

Main Methods:

  • Assessed P5N activity in red blood cells of children aged 2-5 years with varying blood lead levels.
  • Administered lead acetate to rats and monitored blood lead levels and P5N activity over 24 days.
  • Analyzed the correlation between blood lead concentrations and P5N activity, controlling for reticulocyte count.

Main Results:

  • A significant negative linear correlation was observed between blood lead levels and red cell P5N activity in children (r = -0.60, P < 0.01).
  • In rats, P5N activity decreased significantly with increasing blood lead levels (r = -0.85, P < 0.001), showing a similar trend to humans.
  • Lead exposure did not significantly alter hexokinase, hemoglobin, or red cell count at the measured levels.

Conclusions:

  • Red blood cell Pyrimidine 5 omino-nucleotidase (P5N) is a sensitive indicator of lead exposure, even at low levels.
  • P5N activity can be a valuable biomarker for early detection and monitoring of lead toxicity in both pediatric and animal models.
  • Further research can explore P5N's utility in clinical settings for lead poisoning surveillance.

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