𝔖 Bobbio Scriptorium
✦   LIBER   ✦

Noradrenergic modulation of albumin expression in growth-stimulated adult rat hepatocytes in primary culture

✍ Scribed by Isabel Fabregat; Carmen De Juan; CÉSar Roncero; Manuel Benito


Publisher
John Wiley and Sons
Year
1994
Tongue
English
Weight
603 KB
Volume
158
Category
Article
ISSN
0021-9541

No coin nor oath required. For personal study only.

✦ Synopsis


Serum albumin is the most abundant protein synthesized by liver cells, and its production is a reliable indicator of the differentiated state of hepatocytes. We have recently shown that fetal rat hepatocytes cultured under proliferative conditions, i.e., in the presence of EGF, responded to glucagon and noradrenaline increasing albumin protein and mRNA levels (de Juan et al., 1992,. J. Cell. Physiol., 152.95-101). This effect was mimicked by agents that increase cyclic AMP levels. In this report, we show that in regenerating liver, noradrenaline modulation of albumin expression seems to be different. Hepatocytes from hepatectomized rats were cultured at low cell density and in the presence of EGF. Under these conditions, noradrenaline, which acted synergistically with EGF increasing DNA synthesis (de Juan et al., 199%. Exp. Cell. Res., 202:495-500), produced a decrease in albumin mRNA levels. This effect was dose-dependent, being maximum at 1 pM noradrenaline. Noradrenergic effect seemed to be mediated by a,-receptors, because it was blocked by prazosin, but not by propranolol.

Other Ca2+-increasing agents, as vasopressin, angiotensin II, or ATP, did not produce any effect. However, albumin mRNA levels decreased when the cells were incubated in the presence of tetradecanoyl phorbol-13-acetate (TPA), In addition, noradrenergic modulation of albumin expression was blocked by staurosporine, a protein kinase inhibitor with relative specificity for protein kinase C.

Thus we can conclude that the role of noradrenaline on the regulation of liver growth and differentiation changes from fetal to adult life. This change is probably due to its action on different receptors: @-receptors in fetal hepatocytes and a,-receptors in the adult liver. o 1994 Wiley-Liss, Inc.


📜 SIMILAR VOLUMES


Effects of dexamethasone on albumin and
✍ Douglas M. Jefferson; Dr. Lola M. Reid; Marie-Adele Giambrone; David A. Shafritz 📂 Article 📅 1985 🏛 John Wiley and Sons 🌐 English ⚖ 883 KB

To further our studies on collagen gene expression, we have evaluated the molecular basis for the finding that steroids decrease collagen synthesis in cultured hepatocytes. We studied the effects of dexamethasone on primary cultures of adult rat hepatocytes grown on tissue culture plastic in either

Increase in Ornithine Decarboxylase Acti
✍ Ikko Higaki; Isao Matsui-yuasa; Masanobu Terakura; Shuzo Otani; Hiroaki Kinoshit 📂 Article 📅 1993 🏛 John Wiley and Sons 🌐 English ⚖ 433 KB

The effect of hepatocyte growth factor on ornithine decarboxylase activity was studied in primary cultured adult rat hepatocytes. Ornithine decarboxylase activity was increased 3 hr after the addition of hepatocyte growth factor and remained at a high level until 12 hr; thereafter it decreased, and

Norepinephrine modulates the growth-inhi
✍ Keith A. Houck; Jennifer L. Cruise; George Michalopoulos 📂 Article 📅 1988 🏛 John Wiley and Sons 🌐 English ⚖ 565 KB

TGF-beta is a potent inhibitor of EGF-induced DNA synthesis in primary rat hepatocyte cultures. Norepinephrine (NE) was shown to modulate this inhibition of DNA synthesis. It produced a five-fold increase, from 2.8 pM to 14.4 pM, in the IDSo for TGF-beta. The effect was dose-dependent and was signif

Occurrence and possible consequences of
✍ P. M. Eckl 📂 Article 📅 1993 🏛 John Wiley and Sons 🌐 English ⚖ 635 KB

## Abstract Proliferating primary cultures of adult rat hepatocytes are characterized by the occurrence of multipolar mitoses, and chromosome loss resulting in the formation of micronuclei at telophase. The percentage of multipolar mitotic figures was determined to be 12.76 ± 7.9%, 80% of which wer

Regulation of albumin expression in feta
✍ Carmen De Juan; Manuel Benito; Isabel Fabregat 📂 Article 📅 1992 🏛 John Wiley and Sons 🌐 English ⚖ 891 KB

Sustained production of plasma proteins, notably albumin, is a reliable indicator of the differentiated state ot hepatocytes. In this work, we have developed a fetal hepatocyte culture system where studying the regulation of albumin expression in proliferating liver cells. Our results show that unde