Modified arteriolar responses to ATP after impairment of endothelium by light-dye techniques in vivo

Journal Article · Tue Jan 01 00:00:00 EST 1991 · Microvascular Research; (United States)

DOI:https://doi.org/10.1016/0026-2862(91)90008-Y· OSTI ID:5394833

Koller, A; Rodenburg, J M; Wolin, M S; Messina, E J; Kaley, G ^[1]

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1. Department of Physiology, New York Medical College, Valhalla (USA)

In this study we investigated whether endothelial cells are involved in the dilation of third-order arterioles (14 to 22 microns) in response to adenosine triphosphate (ATP) in cremaster muscle of pentobarbital-anesthetized rats. Two light/dye (L/D) techniques were employed to achieve selective, local endothelial impairment. One of these techniques utilizes a mercury lamp and sodium fluorescein, the other a Helium-Neon laser and Evans blue dye. L/D treatment (illumination with the appropriate wavelengths of light in the presence of an intravascular dye) of a 20-to 100-microns segment of an arteriole resulted in a complete loss of arteriolar dilation in response to topical administration of acetylcholine (10(-6) M) and arachidonic acid (AA, 10(-5) M). These agents were applied in 100-microl aliquots without interrupting the continuous suffusion with Ringer-gelatin solution and caused a {approximately} 70% increase in vascular diameter before the L/D intervention. Selectivity of the impairment was assessed by arteriolar responses to the nonendothelium-dependent dilator agents adenosine (10(-5) M) and sodium nitroprusside (2 {times} 10(-7) M), which elicited the same degree of dilation before and after L/D treatment. Under control conditions ATP (10(-6), 10(-5), and 10(-4) M) elicited dose-dependent increases in arteriolar diameter (from 38 to 74%). After impairment of arteriolar endothelium, dilation in response to all doses of ATP was significantly reduced. Theophylline (30 microM) significantly inhibited arteriolar dilation in response to adenosine (10(-6), 10(-5), and 10(-4) M) but did not affect the responses to various doses of ATP. Moreover, impairment of endothelium enhanced constrictor responses of arterioles to norepinephrine (0.6 {times} 10(-8) M).

• OSTI ID: 5394833
• Journal Information: Microvascular Research; (United States), Vol. 41:1; ISSN 0026-2862
• Country of Publication: United States
• Language: English

Related Subjects

63 RADIATION, THERMAL, AND OTHER ENVIRON. POLLUTANT EFFECTS ON LIVING ORGS. AND BIOL. MAT.
ATP
BIOCHEMICAL REACTION KINETICS
ENDOTHELIUM
SENSITIVITY
LASER RADIATION
BIOLOGICAL EFFECTS
ACETYLCHOLINE
ADENOSINE
DOSE-RESPONSE RELATIONSHIPS
DYE LASERS
EVANS BLUE
MUSCLES
PHOTOCHEMISTRY
RATS
THEOPHYLLINE
VASODILATION
AMINES
AMMONIUM COMPOUNDS
ANIMAL TISSUES
ANIMALS
AROMATICS
AUTONOMIC NERVOUS SYSTEM AGENTS
AZAARENES
AZO COMPOUNDS
AZO DYES
BODY
CARDIOVASCULAR AGENTS
CHEMISTRY
DRUGS
DYES
ELECTROMAGNETIC RADIATION
ESTERS
HETEROCYCLIC COMPOUNDS
KINETICS
LASERS
LIQUID LASERS
MAMMALS
NEUROREGULATORS
NUCLEOSIDES
NUCLEOTIDES
ORGANIC ACIDS
ORGANIC COMPOUNDS
ORGANIC NITROGEN COMPOUNDS
ORGANIC OXYGEN COMPOUNDS
ORGANIC SULFUR COMPOUNDS
PARASYMPATHOMIMETICS
PURINES
QUATERNARY COMPOUNDS
RADIATIONS
REACTION KINETICS
REAGENTS
RIBOSIDES
RODENTS
SULFONIC ACIDS
TISSUES
VASODILATORS
VERTEBRATES
XANTHINES
560400* - Other Environmental Pollutant Effects