The glucose-induced switch between glycogen phosphorylase and glycogen synthase in the liver: outlines of a theoretical approach.

نویسندگان

  • M L Cárdenas
  • A Goldbeter
چکیده

The glucose-induced switch between glycogen phosphorylase and glycogen synthase in the liver is investigated by means of a theoretical approach based on a minimal, bicyclic cascade model involving the reversible phosphorylation of the two enzymes. The aim of the analysis is to evaluate the contribution of different factors to the sequential changes in the activity of glycogen phosphorylase and glycogen synthase observed following the addition of suprathreshold amounts of glucose.

برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید

ثبت نام

اگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید

منابع مشابه

Effect of glucopyranosylidene-spiro-thiohydantoin on glycogen metabolism in liver tissues of streptozotocin-induced and obese diabetic rats.

The major role of liver glycogen is to supply glucose to the circulation in order to maintain normal blood glucose levels. In the muscle and liver, the accumulation and breakdown of glycogen are regulated by the reciprocal activities of glycogen phosphorylase and glycogen synthase. Glycogen phosphorylase catalyses the key step of glycogen degradation and its activity is inhibited by glucose and...

متن کامل

Lack of defect in insulin action on hepatic glycogen synthase and phosphorylase in insulin-resistant monkeys.

It is well known that an alteration in insulin activation of skeletal muscle glycogen synthase is associated with insulin resistance. To determine whether this defect in insulin action is specific to skeletal muscle, or also present in liver, simultaneous biopsies of these tissues were obtained before and during a euglycemic hyperinsulinemic clamp in spontaneously obese insulin-resistant male r...

متن کامل

اثر سایپروهپتادین (CYP) بر میزان گلوکز خون و گلیکوژن کبدی در موش های صحرایی (رت)

Background and Purpose: Çyproheptadine (ÇYP) is an antihistaminic and antiserotonine agent with specific property which differentiates it from the other antihistaminics and antiserotonic agent. The appetite stimulating effect of (ÇYP) is well documented in man but its effects on the blood glucose and liver glycogen are not the same. Hence this study was conducted to determine the effects o...

متن کامل

The Effects of Glucose and Fructose on Glycogen Metabolism in the Isolated Perfused Rat Liver

Glycogen metabolism is considered to be regulated by the activities of the a forms of glycogen synthase and phosphorylase. Among other factors, the concentration of circulating blood glucose controls the activities of these two enzymes. It has been shown in experiments in oivo (De Wulf & Hers, 1967; Stalmans et al., 1974), isolated perfused liver (Buschiazzo et al., 1970; Glinsmann et al., 1970...

متن کامل

Molecular mode of inhibition of glycogenolysis in rat liver by the dihydropyridine derivative, BAY R3401: inhibition and inactivation of glycogen phosphorylase by an activated metabolite.

The racemic prodrug BAY R3401 suppresses hepatic glycogenolysis. BAY W1807, the active metabolite of BAY R3401, inhibits muscle glycogen phosphorylase a and b. We investigated whether BAY R3401 reduces hepatic glycogenolysis by allosteric inhibition or by phosphatase-catalyzed inactivation of phosphorylase. In gel-filtered liver extracts, racemic BAY U6751 (containing active BAY W1807) was test...

متن کامل

ذخیره در منابع من


  با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید

برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید

ثبت نام

اگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید

عنوان ژورنال:
  • Journal of theoretical biology

دوره 182 3  شماره 

صفحات  -

تاریخ انتشار 1996