Plasma amino acid concentrations in pregnant rats and in 21-day foetuses

Palou, Andreu Taberner; Arola, Lluı́s; Alemany, M

doi:10.1042/bj1660049

Cited by 57 publications

(35 citation statements)

References 29 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…These results were in agreement with previous studies which have reported a generalised fall in amino acid concentrations in the maternal serum as gestation progresses [11]. However, a 50% decrease in the protein content of the diet has surprisingly modest effects on the concentrations of most amino acids.…”

Section: Discussionsupporting

confidence: 93%

The effect of dietary protein on the amino acid supply and threonine metabolism in the pregnant rat

Rees¹,

Hay²,

Antipatis³

2006

Reprod. Nutr. Dev.

View full text Add to dashboard Cite

-To characterise the effects of dietary protein content on threonine metabolism during pregnancy, rats were fed diets containing 18% or 9% protein and then killed at different stages of gestation. Serum threonine concentrations fell significantly faster in the animals fed the diet containing 9% protein when compared to those fed the diet containing 18% protein. On day 4 of gestation the rate of threonine oxidation was higher in maternal liver homogenates prepared from the animals fed the diet containing 18% protein. The rate of threonine oxidation by liver homogenates fell as gestation proceeded in both diet groups. The activity of threonine dehydrogenase in the maternal liver was unaffected by dietary protein content at all stages of gestation. Serine-threonine dehydratase activity in homogenates of the maternal liver was transiently increased during the early stages of gestation in the animals fed high protein diets but was unchanged in the low protein groups. There was an increase in serine-threonine dehydratase activity in the kidney during the later stages of gestation but this was unaffected by the protein content of the maternal diet. These data show that the changes in free threonine concentrations cannot be accounted for through changes in the oxidation rate and suggest that some other factor influences the unusual metabolism of this amino acid during gestation. threonine dehydratase / threonine dehydrogenase / protein metabolism / pregnancy / foetus / metabolic programming Abbreviations: SDH, serine/threonine dehydratase; TDH, threonine dehydrogenase; PCA, perchloric acid; TCA, trichloroacetic acid.

show abstract

Section: Discussionsupporting

confidence: 93%

The effect of dietary protein on the amino acid supply and threonine metabolism in the pregnant rat

Rees¹,

Hay²,

Antipatis³

2006

Reprod. Nutr. Dev.

View full text Add to dashboard Cite

show abstract

“…The enhanced sensitivity of the secretory process in our study is probably explained by the high concentration of amino acids in the incubation medium. These levels were chosen to replicate the physiological elevation of amino acids seen in the near-term [17] and neonatal rat [21]. Kervran and Randon [22] demonstrated that insulin release in response to glucose in the perifused fetal rat pancreas is potentiated by such elevated amino acid concentrations.…”

Section: Discussionmentioning

confidence: 99%

“…The amino acid concentration was further supplemented to 10 mmol/l with the essential and non-essential amino acids found in the near-term fetal rat aminogram [17]. The concentration of glucose was adjusted between 1.6 and 16.7 mmol/1 by the addition of D-glucose in a final incubation volume of 1.0 ml.…”

Section: Immunoreactive Insulin Released In Response To Glucosementioning

confidence: 99%

The effect of maternal caffeine ingestion on pancreatic function in the neonatal rat

1982

View full text Add to dashboard Cite

Summary. Pancreatic function was investigated in neonatal suckling offspring of caffeine-ingesting dams, with or without maternal sucrose supplementation, throughout pregnancy and lactation. In offspring of rats ingesting caffeine without sucrose supplementation, there was initial hyperinsulinaemia, followed by a progressive fall of plasma insulin to subnormal levels. This fall in plasma insulin coincided with depletion of pancreatic insulin stores. Both the fall in plasma insulin and depletion of pancreatic insulin stores were prevented by sucrose supplementation of caffeine-ingesting dams. Offspring of dams fed sucrose alone and control offspring also maintained pancreatic insulin stores and circulating insulin levels over the first 14 days of postnatal life. Pancreases from offspring of caffeine-exposed animals tested in vitro showed enhanced sensitivity of the insulin release process to glucose. This was reflected in the glucose concentration required to elicit half-maximal insulin release (2.4 ___ 0.2 mmol/1 for caffeine offspring, 2.3 + 0.2 mmol/1 for caffeine with sucrose, 3.8 _+ 0.3 mmol/1 for sucrose and 4.1 + 0.3 mmol/1 for control offspring, mean +_ SEM). In contrast, offspring of sucrose-supplemented (with or without caffeine) dams showed increased sensitivity of the proinsulin biosynthetic process to glucose, whereas offspring of dams ingesting caffeine alone showed no significant enhancement of the biosynthetic process compared with control offspring. Thus enhanced sensitivity of the insulin secretory process to glucose without a change in the sensitivity of the biosynthetic process in the offspring of the caffeine ingesting (nonsucrose supplemented) dams could explain the progressive depletion of pancreatic insulin stores and eventual hypoinsulinaemia seen in this group.

show abstract

“…In this study, the marked decrease of amino acid concentrations in maternal plasma was observed, when pregnant rats were administered with 2 µg of rhIGF-I. Maternal plasma amino acid levels were kept low during pregnant period compared with those in the nonpregnant rat, probably because the enhancement of active amino acid transport from the mother to the fetus via placenta [13]. IGF-I might enhance some amino acid transfer by the placental uptake, by which decreased amino acid concentrations in the mother.…”

mentioning

confidence: 92%

“…In contrast, fetal plasma amino acid concentrations showed no significant changes over control. The ratios of fetal/maternal plasma amino acid concentrations were calculated as an index of placental amino acid transport activities [1,13,18]. The ratios of 6 amino acids (arginine, isoleucine, leucine, tryptophan, phenylalanine, and tyrosine) at 2 µg and 2 amino acids (alanine and tyrosine) at 4 µg of rhIGF-I treated groups were significantly higher (P<0.01) than those in the control.…”

mentioning

confidence: 99%

Effects of Isulin-like Growth Factor-I on Maternal and Fetal Plasma Amino Acid Levels in Pregnant Rats.

Thongsong

Bonkobara

Matsumoto

et al. 2002

The Journal of Veterinary Medical Science

View full text Add to dashboard Cite

ABSTRACT. Pregnant rats were subcutaneously administered with recombinant human insulin-like growth factor-I (rhIGF-I) in doses of 0 (control), 1, 2, and 4 µg/g body weight per day from day 18 to 21 of pregnancy. On day 21 of pregnancy, maternal and fetal plasma samples were collected and those amino acid levels were measured. The ratios of fetal/maternal plasma amino acids, especially l eucine, isoleucine, tryptophan, phenylalanine and tyrosine, increased in 2 µg rhIGF-I treated group. Both total fetal weight and total placental weight were also higher than those in the control group. These results suggested that IGF-I enhanced fetal growth by, as one of its possible mechanisms, promoting placental amino acid supplies from the mother to fetuses. KEY WORDS: insulin-like growth factor-I (IGF-I), plasma amino acid, pregnant rat.J. Vet. Med. Sci. 64(9): 859-861, 2002 Insulin-like growth factor-I (IGF-I) is widely known to be a major growth factor for many types of cells including placental cell [4] and also an important regulatory factor for fetal growth and development [11,16]. Fetal tissue and placenta expressed a large number of IGF receptor [12,14]. Gluckman et al. [6] demonstrated that the administration of recombinant human IGF-I (rhIGF-I) to pregnant rats enhanced fetal growth. In most species, maternal serum levels of IGF-I correlated positively with fetal and/or placental weight [7,15]. On the other hand, the supply of amino acids from the mother to fetuses via placenta is crucial importance for fetal growth. The full term fetal weight was reduced by the starvation at late phase of pregnancy with the decrease of fetal plasma amino acids level and also fetal/maternal plasma amino acids ratio in the rat [1]. Impaired fetal and placental uptake of amino acids has been observed in several models of growth retardation in the rat [8]. This note deals with the effects of IGF-I on maternal and fetal plasma amino acid concentrations in pregnant rats.Timed pregnant Wister ST rats (weighing 250-270 g) were obtained from Japan SLC (Shizuoka, Japan) and divided into four treatment groups. The rats were housed in standardized cages with controlled temperature under a 12-hr light-dark cycle and received standard rat chow and drinking water ad libitum. The rats were subcutaneously administered with rhIGF-I (Fujisawa Pharmaceutical Co., Ltd., Osaka, Japan) in doses of 0 (control), 1, 2, and 4 µg/g body weight per day in 0.6 ml of physiological saline, based on the previous reports [2,5,6] and our preliminary study. The total of 6 administrations was given every 12 hr to each rat starting from at 19:00 on day 18 of pregnancy. Three hours after the final administration on day 21, 1 day before delivery, the rats were anesthetized with diethyl ether. Then, blood samples collected from maternal artery were transferred into heparinized tubes on ice and centrifuged at 1,500 × g for 10 min at 4°C. Plasma samples were separated and stored at -20°C until assay. After blood sampling, individual placentas and fetuses were removed ...

show abstract

Plasma amino acid concentrations in pregnant rats and in 21-day foetuses

Cited by 57 publications

References 29 publications

The effect of dietary protein on the amino acid supply and threonine metabolism in the pregnant rat

The effect of dietary protein on the amino acid supply and threonine metabolism in the pregnant rat

The effect of maternal caffeine ingestion on pancreatic function in the neonatal rat

Effects of Isulin-like Growth Factor-I on Maternal and Fetal Plasma Amino Acid Levels in Pregnant Rats.

Contact Info

Product

Resources

About