Brain large neutral amino acids and catecholamines in parenterally nourished preterm rabbits

Suzanne M. Lopez, David K. Rassin

Research output: Contribution to journalArticle

2 Citations (Scopus)

Abstract

Total parenteral nutrition (TPN) has been adapted as a standard for providing nutrition to ill term and preterm infants. The availability of tyrosine in amino acid preparations utilized for TPN is limited and may potentiate a tyrosine-deficient state. Phenlyalanine hydroxylase activity, responsible for catalyzing tyrosine synthesis, has been suggested to be decreased in fetal and neonatal animals. Parenterally nourished premature rabbits (n=16) and suckled rabbits (n=19) were studied in order to compare growth parameters and amino acids in the plasma and brain, as well as whole brain catecholamine concentrations. Influx velocities into the brain of amino acids were also determined in these two groups. The preterm rabbit's average birth weight (42.6±6.0) was less than that of term rabbits (56.7±8.7, P<0.005). Significantly lower concentrations of the catecholamine precursor tyrosine were found in both the plasma and brain of the parenterally nourished animals compared to the suckled animals. Tyrosine is reduced in the brain in TPN-supported animals reflecting both low tyrosine intake and increased plasma concentrations of large neutral amino acids that compete for uptake at the blood-brain barrier. However, no difference was observed between the two groups in their brain catecholamine concentrations. The seven-day parenterally nourished rabbit appears to be tyrosine-deficient but no evident effects on brain catecholamine concentrations were seen. The effects and impact of a tyrosine-deficient state might better be evaluated by regional evaluation of catecholaminergic areas of the brain or over a longer period of parenteral nutrition.

Original languageEnglish (US)
Pages (from-to)619-626
Number of pages8
JournalInternational Journal of Developmental Neuroscience
Volume13
Issue number6
DOIs
StatePublished - 1995

Fingerprint

Neutral Amino Acids
Catecholamines
Tyrosine
Rabbits
Brain
Total Parenteral Nutrition
Amino Acids
Newborn Animals
Parenteral Nutrition
Mixed Function Oxygenases
Blood-Brain Barrier
Birth Weight
Premature Infants

Keywords

  • amino acids
  • catecholamine
  • development
  • nutrition
  • parenteral nutrition
  • phenylalanine
  • tyrosine

ASJC Scopus subject areas

  • Developmental Biology
  • Developmental Neuroscience

Cite this

Brain large neutral amino acids and catecholamines in parenterally nourished preterm rabbits. / Lopez, Suzanne M.; Rassin, David K.

In: International Journal of Developmental Neuroscience, Vol. 13, No. 6, 1995, p. 619-626.

Research output: Contribution to journalArticle

@article{cc09283830a5485e901cbde34874ccf6,
title = "Brain large neutral amino acids and catecholamines in parenterally nourished preterm rabbits",
abstract = "Total parenteral nutrition (TPN) has been adapted as a standard for providing nutrition to ill term and preterm infants. The availability of tyrosine in amino acid preparations utilized for TPN is limited and may potentiate a tyrosine-deficient state. Phenlyalanine hydroxylase activity, responsible for catalyzing tyrosine synthesis, has been suggested to be decreased in fetal and neonatal animals. Parenterally nourished premature rabbits (n=16) and suckled rabbits (n=19) were studied in order to compare growth parameters and amino acids in the plasma and brain, as well as whole brain catecholamine concentrations. Influx velocities into the brain of amino acids were also determined in these two groups. The preterm rabbit's average birth weight (42.6±6.0) was less than that of term rabbits (56.7±8.7, P<0.005). Significantly lower concentrations of the catecholamine precursor tyrosine were found in both the plasma and brain of the parenterally nourished animals compared to the suckled animals. Tyrosine is reduced in the brain in TPN-supported animals reflecting both low tyrosine intake and increased plasma concentrations of large neutral amino acids that compete for uptake at the blood-brain barrier. However, no difference was observed between the two groups in their brain catecholamine concentrations. The seven-day parenterally nourished rabbit appears to be tyrosine-deficient but no evident effects on brain catecholamine concentrations were seen. The effects and impact of a tyrosine-deficient state might better be evaluated by regional evaluation of catecholaminergic areas of the brain or over a longer period of parenteral nutrition.",
keywords = "amino acids, catecholamine, development, nutrition, parenteral nutrition, phenylalanine, tyrosine",
author = "Lopez, {Suzanne M.} and Rassin, {David K.}",
year = "1995",
doi = "10.1016/0736-5748(95)00041-E",
language = "English (US)",
volume = "13",
pages = "619--626",
journal = "International Journal of Developmental Neuroscience",
issn = "0736-5748",
publisher = "Elsevier Limited",
number = "6",

}

TY - JOUR

T1 - Brain large neutral amino acids and catecholamines in parenterally nourished preterm rabbits

AU - Lopez, Suzanne M.

AU - Rassin, David K.

PY - 1995

Y1 - 1995

N2 - Total parenteral nutrition (TPN) has been adapted as a standard for providing nutrition to ill term and preterm infants. The availability of tyrosine in amino acid preparations utilized for TPN is limited and may potentiate a tyrosine-deficient state. Phenlyalanine hydroxylase activity, responsible for catalyzing tyrosine synthesis, has been suggested to be decreased in fetal and neonatal animals. Parenterally nourished premature rabbits (n=16) and suckled rabbits (n=19) were studied in order to compare growth parameters and amino acids in the plasma and brain, as well as whole brain catecholamine concentrations. Influx velocities into the brain of amino acids were also determined in these two groups. The preterm rabbit's average birth weight (42.6±6.0) was less than that of term rabbits (56.7±8.7, P<0.005). Significantly lower concentrations of the catecholamine precursor tyrosine were found in both the plasma and brain of the parenterally nourished animals compared to the suckled animals. Tyrosine is reduced in the brain in TPN-supported animals reflecting both low tyrosine intake and increased plasma concentrations of large neutral amino acids that compete for uptake at the blood-brain barrier. However, no difference was observed between the two groups in their brain catecholamine concentrations. The seven-day parenterally nourished rabbit appears to be tyrosine-deficient but no evident effects on brain catecholamine concentrations were seen. The effects and impact of a tyrosine-deficient state might better be evaluated by regional evaluation of catecholaminergic areas of the brain or over a longer period of parenteral nutrition.

AB - Total parenteral nutrition (TPN) has been adapted as a standard for providing nutrition to ill term and preterm infants. The availability of tyrosine in amino acid preparations utilized for TPN is limited and may potentiate a tyrosine-deficient state. Phenlyalanine hydroxylase activity, responsible for catalyzing tyrosine synthesis, has been suggested to be decreased in fetal and neonatal animals. Parenterally nourished premature rabbits (n=16) and suckled rabbits (n=19) were studied in order to compare growth parameters and amino acids in the plasma and brain, as well as whole brain catecholamine concentrations. Influx velocities into the brain of amino acids were also determined in these two groups. The preterm rabbit's average birth weight (42.6±6.0) was less than that of term rabbits (56.7±8.7, P<0.005). Significantly lower concentrations of the catecholamine precursor tyrosine were found in both the plasma and brain of the parenterally nourished animals compared to the suckled animals. Tyrosine is reduced in the brain in TPN-supported animals reflecting both low tyrosine intake and increased plasma concentrations of large neutral amino acids that compete for uptake at the blood-brain barrier. However, no difference was observed between the two groups in their brain catecholamine concentrations. The seven-day parenterally nourished rabbit appears to be tyrosine-deficient but no evident effects on brain catecholamine concentrations were seen. The effects and impact of a tyrosine-deficient state might better be evaluated by regional evaluation of catecholaminergic areas of the brain or over a longer period of parenteral nutrition.

KW - amino acids

KW - catecholamine

KW - development

KW - nutrition

KW - parenteral nutrition

KW - phenylalanine

KW - tyrosine

UR - http://www.scopus.com/inward/record.url?scp=0029163327&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=0029163327&partnerID=8YFLogxK

U2 - 10.1016/0736-5748(95)00041-E

DO - 10.1016/0736-5748(95)00041-E

M3 - Article

VL - 13

SP - 619

EP - 626

JO - International Journal of Developmental Neuroscience

JF - International Journal of Developmental Neuroscience

SN - 0736-5748

IS - 6

ER -