A myo-inositol pool utilized for phosphatidylinositol synthesis is depleted in sciatic nerve from rats with streptozotocin-induced diabetes

Journal Article · Sat Dec 01 00:00:00 EST 1990 · Proceedings of the National Academy of Sciences of the United States of America; (United States)

DOI:https://doi.org/10.1073/pnas.87.24.9818· OSTI ID:5044312

Zhu, Xi; Eichberg, J ^[1]

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1. Univ. of Houston, TX (United States)

Peripheral nerve from experimentally diabetic rats exhibits lowered levels of myo-inositol (MI) and decreased incorporation of ({sup 3}H)MI into phosphatidylinositol (PI). There are indications that diminished PI turnover may be causally related to reduced Na{sup +}, K{sup +} -ATPase activity in diabetic nerve. The authors have investigated whether a metabolic compartment of MI that is essential for PI synthesis is decreased in this tissue. Sciatic nerve segments form streptozotocin-induced diabetic and age-matched normal rats were incubated in vitro with either {sup 32}P{sub i} or ({sup 3}H)cytidine in the presence of propranolol. This cationic amphiphilic agent redirected nerve phospholipid metabolism to produce enhanced {sup 32}P incorporation into PI and decreased labeling of phosphatidylcholine and phosphatidyl-ethanolamine. The incorporation of ({sup 3}H)cytidine into CMP-PA in normal nerve increased up to 15-fold when 0.6 mM propranolol was present. These results strongly suggest the presence in nerve of a pool of MI that is not in equilibrium with the bulk of nerve MI and that is preferentially used for PI synthesis. This metabolic compartment is depleted in diabetic nerve but can be readily replenished by exogenous MI and may correspond to the MI pool that has been proposed to be required for the turnover of a portion of tissue PI involved in maintenance of normal Na{sup +}, K{sup +} -ATPase activity.

• OSTI ID: 5044312
• Journal Information: Proceedings of the National Academy of Sciences of the United States of America; (United States), Vol. 87:24; ISSN 0027-8424
• Country of Publication: United States
• Language: English

Related Subjects

59 BASIC BIOLOGICAL SCIENCES
DIABETES MELLITUS
BIOCHEMISTRY
PHOSPHOLIPIDS
AUTORADIOGRAPHY
TRITIUM COMPOUNDS
LABELLED POOL TECHNIQUES
ATP-ASE
BIOSYNTHESIS
CYTIDINE
INOSITOLS
PHOSPHORUS 32
SCIATIC NERVE
STREPTOZOCIN
THIN-LAYER CHROMATOGRAPHY
ACID ANHYDRASES
ANTI-INFECTIVE AGENTS
ANTIBIOTICS
ANTINEOPLASTIC DRUGS
AZINES
BETA DECAY RADIOISOTOPES
BETA-MINUS DECAY RADIOISOTOPES
CARBOHYDRATES
CHEMISTRY
CHROMATOGRAPHY
DAYS LIVING RADIOISOTOPES
DISEASES
DRUGS
ENDOCRINE DISEASES
ENZYMES
ESTERS
HETEROCYCLIC COMPOUNDS
HYDROGEN COMPOUNDS
HYDROLASES
ISOTOPE APPLICATIONS
ISOTOPES
LIGHT NUCLEI
LIPIDS
METABOLIC DISEASES
MONOSACCHARIDES
NERVES
NERVOUS SYSTEM
NUCLEI
NUCLEOSIDES
NUCLEOTIDES
ODD-ODD NUCLEI
ORGANIC COMPOUNDS
ORGANIC NITROGEN COMPOUNDS
ORGANIC PHOSPHORUS COMPOUNDS
PHOSPHOHYDROLASES
PHOSPHORUS ISOTOPES
PYRIMIDINES
RADIOISOTOPES
RIBOSIDES
SACCHARIDES
SEPARATION PROCESSES
SYNTHESIS
TRACER TECHNIQUES
550201* - Biochemistry- Tracer Techniques