Fogorvosi szemle, 1996 (89. évfolyam, 1-12. szám)

1996-04-01 / 4. szám

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Dr. Fazekas, Á., dr. Irmes, F., dr. Monos, Á., dr. Györfi, A., dr. Rosivall, L.: Role of nitric oxide in the regulation of basal blood flow to the oral structures in anaesthetised rats

In order to evaluate the contribution of basal NO formation to control of organ blood supply, regional blood flow distribution within the oral region (dental pulp, submandibular gland, oral mucosa, tongue) was assessed with (II), and without (I) NG- nitro-L-arginine methyl ester (L-NAME; 10 mg kg-1) pretreatment in anaesthetized rats. In a group of animals (III) mean arterial pressure (MAP) elevation caused by L-NAME was normalized by hemorrhage (He) prior to blood flow registrations. MAP was recorded continuously, regional blood flows were determined by 86Rb uptake technique. To allow comparisons, vascular conductances (VC) were calculated. Bolus injection of LNAME resulted in MAP elevation by about 20% both in group II and group III. L-NAME and L-NAME + He caused significant reduction in cardiac output. There was also a significant decrease in VC after L-NAME in all tissues tested. The highest decrease of VC could be registered in the dental pulp (66%). L-NAME + He evoked further reduction on the calculated VC values.

Our results suggest, that NO plays significant role in the regulation of basal blood perfusion and vascular autoregulation of the oral structures.

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