Biomaterial Database

Nitric oxide synthase inhibition attenuates hypoglycemic cerebral hyperemia in piglets. 1994

R N Ichord, and M A Helfaer, and J R Kirsch, and D Wilson, and R J Traystman

Department of Neurology, Johns Hopkins Medical Institutions, Baltimore, Maryland 21287.

We tested the hypothesis that nitric oxide (NO) mediates hypoglycemia-induced cerebral vasodilation in piglets. Piglets (1-2 wk old) were made hypoglycemic with insulin (200 U/kg i.v.) with and without an NO synthase inhibitor, N omega-nitro-L-arginine methyl ester (L-NAME, 40 mg/kg i.v.). Electroencephalogram (EEG), cerebral O2 consumption (CMRO2), and cerebral blood flow (CBF) were measured before L-NAME and insulin and for 180 min after insulin. Hypoglycemia led to isoelectric EEG earlier after L-NAME (87 +/- 8 min) than without L-NAME pretreatment (132 +/- 13 min). CBF increased in all brain regions during hypoglycemia at the onset of isoelectric EEG and was associated with increased CMRO2.L-NAME prevented the increase in CMRO2 and attenuated vasodilation in forebrain (154 +/- 37 vs. 400 +/- 60%), cerebellum (251 +/- 52 vs. 386 +/- 52%), and cortical gray matter (183 +/- 47 vs. 524 +/- 93%) but had no effect on CBF responses in brain stem, thalamus, caudate, or hippocampus. We conclude that NO or a NO-containing compound mediates cerebral vasodilation induced by profound insulin-hypoglycemia in piglets and that this vasodilation plays an important role in the adaptation of immature brain to hypoglycemia.

UI	MeSH Term	Description	Entries
D007003	Hypoglycemia	A syndrome of abnormally low BLOOD GLUCOSE level. Clinical hypoglycemia has diverse etiologies. Severe hypoglycemia eventually lead to glucose deprivation of the CENTRAL NERVOUS SYSTEM resulting in HUNGER; SWEATING; PARESTHESIA; impaired mental function; SEIZURES; COMA; and even DEATH.	Fasting Hypoglycemia,Postabsorptive Hypoglycemia,Postprandial Hypoglycemia,Reactive Hypoglycemia,Hypoglycemia, Fasting,Hypoglycemia, Postabsorptive,Hypoglycemia, Postprandial,Hypoglycemia, Reactive
D007328	Insulin	A 51-amino acid pancreatic hormone that plays a major role in the regulation of glucose metabolism, directly by suppressing endogenous glucose production (GLYCOGENOLYSIS; GLUCONEOGENESIS) and indirectly by suppressing GLUCAGON secretion and LIPOLYSIS. Native insulin is a globular protein comprised of a zinc-coordinated hexamer. Each insulin monomer containing two chains, A (21 residues) and B (30 residues), linked by two disulfide bonds. Insulin is used as a drug to control insulin-dependent diabetes mellitus (DIABETES MELLITUS, TYPE 1).	Iletin,Insulin A Chain,Insulin B Chain,Insulin, Regular,Novolin,Sodium Insulin,Soluble Insulin,Chain, Insulin B,Insulin, Sodium,Insulin, Soluble,Regular Insulin
D009569	Nitric Oxide	A free radical gas produced endogenously by a variety of mammalian cells, synthesized from ARGININE by NITRIC OXIDE SYNTHASE. Nitric oxide is one of the ENDOTHELIUM-DEPENDENT RELAXING FACTORS released by the vascular endothelium and mediates VASODILATION. It also inhibits platelet aggregation, induces disaggregation of aggregated platelets, and inhibits platelet adhesion to the vascular endothelium. Nitric oxide activates cytosolic GUANYLATE CYCLASE and thus elevates intracellular levels of CYCLIC GMP.	Endogenous Nitrate Vasodilator,Mononitrogen Monoxide,Nitric Oxide, Endothelium-Derived,Nitrogen Monoxide,Endothelium-Derived Nitric Oxide,Monoxide, Mononitrogen,Monoxide, Nitrogen,Nitrate Vasodilator, Endogenous,Nitric Oxide, Endothelium Derived,Oxide, Nitric,Vasodilator, Endogenous Nitrate
D002560	Cerebrovascular Circulation	The circulation of blood through the BLOOD VESSELS of the BRAIN.	Brain Blood Flow,Regional Cerebral Blood Flow,Cerebral Blood Flow,Cerebral Circulation,Cerebral Perfusion Pressure,Circulation, Cerebrovascular,Blood Flow, Brain,Blood Flow, Cerebral,Brain Blood Flows,Cerebral Blood Flows,Cerebral Circulations,Cerebral Perfusion Pressures,Circulation, Cerebral,Flow, Brain Blood,Flow, Cerebral Blood,Perfusion Pressure, Cerebral,Pressure, Cerebral Perfusion
D004569	Electroencephalography	Recording of electric currents developed in the brain by means of electrodes applied to the scalp, to the surface of the brain, or placed within the substance of the brain.	EEG,Electroencephalogram,Electroencephalograms
D005990	Glycerol	A trihydroxy sugar alcohol that is an intermediate in carbohydrate and lipid metabolism. It is used as a solvent, emollient, pharmaceutical agent, or sweetening agent.	1,2,3-Propanetriol,Glycerin,1,2,3-Trihydroxypropane,Glycerine
D006940	Hyperemia	The presence of an increased amount of blood in a body part or an organ leading to congestion or engorgement of blood vessels. Hyperemia can be due to increase of blood flow into the area (active or arterial), or due to obstruction of outflow of blood from the area (passive or venous).	Active Hyperemia,Arterial Hyperemia,Passive Hyperemia,Reactive Hyperemia,Venous Congestion,Venous Engorgement,Congestion, Venous,Engorgement, Venous,Hyperemia, Active,Hyperemia, Arterial,Hyperemia, Passive,Hyperemia, Reactive,Hyperemias,Hyperemias, Reactive,Reactive Hyperemias
D000594	Amino Acid Oxidoreductases	A class of enzymes that catalyze oxidation-reduction reactions of amino acids.	Acid Oxidoreductases, Amino,Oxidoreductases, Amino Acid
D000818	Animals	Unicellular or multicellular, heterotrophic organisms, that have sensation and the power of voluntary movement. Under the older five kingdom paradigm, Animalia was one of the kingdoms. Under the modern three domain model, Animalia represents one of the many groups in the domain EUKARYOTA.	Animal,Metazoa,Animalia
D001120	Arginine	An essential amino acid that is physiologically active in the L-form.	Arginine Hydrochloride,Arginine, L-Isomer,DL-Arginine Acetate, Monohydrate,L-Arginine,Arginine, L Isomer,DL Arginine Acetate, Monohydrate,Hydrochloride, Arginine,L Arginine,L-Isomer Arginine,Monohydrate DL-Arginine Acetate