ΛΕΙΤΟΥΡΓΙΚΟΤΗΤΑ ΤΟΥ ΑΓΓΕΙΑΚΟΥ ΠΝΕΥΜΟΝΙΚΟΥ ΕΝΔΟΘΗΛΙΟΥ, IN VIVO, ΥΠΟ ΦΥΣΙΟΛΟΓΙΚΕΣ ΚΑΙ ΠΑΘΟΛΟΓΙΚΕΣ ΣΥΝΘΗΚΕΣ

BESIDES GAS EXCHANGE, THE PULMONARY CIRCULATION HAS ANOTHER IMPORTANT FUNCTION,A METABOLIC ONE. PULMONARY VASCULAR ENDOTHELIUM PARTICIPATES IN VARIOUS IMPORTANT PHYSIOLOGIC AND PHARMACOKINETIC PROCESSES WHICH ARE SUSCEPTIBLE TO DIFFERENT PHARMACOLOGICAL, PHYSICAL AND TOXIC AGENTS. UNDER PATHOLOGICAL CONDITIONS, SUCH AS LUNG INJURY SECONDARY TO RADIATION DELIVERY TO THE CHEST, ENDOTHELIAL-ASSOCIATED-ENZYME ACTIVITIES CAN BE IMPAIRED. WE INVESTIGATED THE EARLY EFFECTS OFIONIZING RADIATION ON PULMONARY ENDOTHELIAL FUNCTIONS IN RABBITS EXPOSED TO A SINGLE DOSE (30 GY) OF IONIZING RADIATION TO THE CHEST, WITH OR WITHOUT POST-RADIATION INDOMETHACIN ADMINISTRATION. THE RESULTS OF OUR STUDY REVEALED THE FOLLOWING: 1) INCREASING PULMONARY BLOOD FLOW LEVELS INCREASED PERFUSED MICROVASCULAR SURFACE AREA, AS REFLECTED IN THE PROPORTIONALLY INCREASING AMAX/KM OR BMAX VALUES FOR ALL SUBSTRATES AND INHIBITOR, RESPECTIVELY, FOR BOTH ACE AND NCT, INCONTROL AND IRRADIATED ANIMALS. 2) IONIZING RADIATION TO THE CHEST PRODUCED ENDOTHELIAL ECTOENZYME DYSFUNCTION, AS REFLECTED IN THE ALTERED ENZYME KINETICS AND SUBSTRATE METABOLISM, WHICH WERE PRESENT WITHIN A WIDE RANGE OF PHYSIOLOGIC PULMONARY BLOOD FLOW VALUES. 3) POST-RADIATION ADMINISTRATION OF INDOMETHACIN CORRECTED OR PREVENTED MOST EVIDENCE OF RADIATION- INDUCED ENDOTHELIAL DYSFUNCTION, BUT IT FAILED TO REVERSE THE RADIATION-INDUCED DEPRESSION OF THE BINDING OFACE WITH ITS INHIBITOR (RAC-X-65). 4) THE CORRECTIVE OR PROTECTIVE ACTIONS OF INDOMETHACIN APPEAR TO INVOLVE DIRECT CYTOPROTECTION RATHER THAN SHUNTING OF THE BLOOD THROUGH NORMAL OR LESS INJURED VESSELS. (SHORTENED)

Grantor dc:publisher

University of Ioannina

Year dc:date

1989

Authors dc:creator

• Orfanos, Stylianos
• Ορφανός, Στυλιανός

• 5'-ΝΟΥΚΛΕΟΤΙΔΑΣΗ (NCT)
• Ενδοθήλιο
• Ινδομεθακίνη
• Ιονίζουσα ακτινοβολία
• Μετατρεπτικό ένζυμο αγγειοτενσίνης (ACE)
• ΜΟΝΤΕΛΟ ΚΑΡΔΙΑΚΗΣ ΠΑΡΑΚΑΜΨΗΣ
• Πνεύμονες
• 5'-NUCLEOTIDASE (NCT)
• Angiotensin converting enzyme
• Endothelium
• HEART BYPASS MODEL
• Indomethacin
• Ionizing radiation
• Lungs
• Ιατρική και Επιστήμες Υγείας
• Κλινική Ιατρική
• Medical and Health Sciences
• Clinical Medicine

Language dc:language

gre

Identifier

10.12681/eadd/1116

OAI identifier oai:identifier

oai:10442/1116