Hormonal regulation of hepatic glycogenolysis in the carp, Cyprinus carpio
Carp (Cyprinus carpio) liver maintained normal glycogen content and enzyme complement for several days in organ culture. Epinephrine-stimulated glycogenolysis, phosphorylase activation, and cyclic AMP (cAMP) accumulation in a concentration-dependent manner with EC/sub 50/s of 100, 100, and 500 nM, respectively. These actions were blocked by the ..beta..-adrenergic antagonist, propranolol, but not by the ..cap alpha..-adrenergic antagonist phentolamine. Glycogenolysis and tissue cAMP were uninfluenced by 10/sup -6/ M arginine vasotocin, arginine vasopressin, lysine vasotocin, lysine vasopressin, mesotocin, or oxytocin, but were slightly increased by 10/sup -5/ M isotocin and slightly decreased by 10/sup -6/ M angiotensin II. (/sup 125/I)-iodocyanopindolol (ICP), a ..beta..-adrenergic ligand, bound to isolated carp liver membranes with a K/sub D/ of 83 pM. Maximum binding of 45 fmol/mg protein was at 600 pM. Propranolol, isoprenaline, epinephrine, phenylephrine, norepinephrine, and phenoxybenzamine displaced ICP with K/sub D/s of 100 nM, 2, 20, 20, 60, and 200 ..mu..M, respectively. The ..cap alpha..-adrenergic antagonists, yohimbine and prazosin, showed no specific binding. These data provide evidence that catecholamines act via ..beta..-adrenergic receptors in carp liver and that ..cap alpha..-adrenergic receptors are not present. Vasoactive peptides play no significant role in regulation of carp liver glycogenolysis.
- Research Organization:
- Australian National Univ., Canberra
- OSTI ID:
- 5879269
- Journal Information:
- Am. J. Physiol.; (United States), Journal Name: Am. J. Physiol.; (United States) Vol. 252:4; ISSN AJPHA
- Country of Publication:
- United States
- Language:
- English
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59 BASIC BIOLOGICAL SCIENCES
ADRENAL HORMONES
ADRENALINE
AMINES
ANGIOTENSIN
ANIMALS
AQUATIC ORGANISMS
AROMATICS
AUTONOMIC NERVOUS SYSTEM AGENTS
BETA DECAY RADIOISOTOPES
BIOCHEMICAL REACTION KINETICS
BIOCHEMISTRY
BODY
CARBOHYDRATES
CARDIOTONICS
CARDIOVASCULAR AGENTS
CATECHOLAMINES
CHEMICAL REACTIONS
CHEMISTRY
DAYS LIVING RADIOISOTOPES
DECOMPOSITION
DIGESTIVE SYSTEM
DRUGS
ELECTRON CAPTURE RADIOISOTOPES
ENZYMATIC HYDROLYSIS
ENZYME ACTIVITY
ENZYMES
FISHES
GLANDS
GLOBULINS
GLYCOGEN
HORMONES
HYDROLYSIS
HYDROXY COMPOUNDS
INTERMEDIATE MASS NUCLEI
IODINE 125
IODINE ISOTOPES
ISOTOPES
KINETICS
LABELLED COMPOUNDS
LIGANDS
LIVER
LYSIS
MEMBRANE PROTEINS
NEUROREGULATORS
NORADRENALINE
NUCLEI
ODD-EVEN NUCLEI
ORGANIC COMPOUNDS
ORGANS
PEPTIDE HORMONES
PEPTIDES
PHENOLS
PHOSPHORUS-GROUP TRANSFERASES
PHOSPHOTRANSFERASES
PITUITARY HORMONES
POLYPHENOLS
POLYSACCHARIDES
PROTEINS
RADIOISOTOPES
REACTION KINETICS
RECEPTORS
SACCHARIDES
SOLVOLYSIS
SYMPATHOMIMETICS
TRANSFERASES
UPTAKE
VASOCONSTRICTORS
VASOPRESSIN
VERTEBRATES