Page 77 - Effects of radiotherapy and hyperbaric oxygen therapy on oral microcirculation Renee Helmers

were housed separately in large cages (R-SUITE Enriched Rabbit Housing,
Techniplast SpA, Buguggiate (Varese), Italy) in a 24-hour light-controlled
room (12 h light/dark cycle) that was maintained at a constant temperature
of 22±1oC and humidity of 55±10%. Consumption of standard food pellet diet
(LK-04, AB Diets, Woerden, The Netherlands) and water (acidified to pH 2.7)
was available ad libitum. Sedation to perform microcirculation measurements,
blood sampling and administration of RT, was achieved though administration
of subcutaneous injection of a mixture of ketamine (Nimatek, Eurovet Animal
Health BV, Bladel, The Netherlands; 15 mg·kg-1) and dexmedetomidine (Dexdomitor, Pfizer Animal Health BV, Capelle aan den Ijssel, The Netherlands;
0.2 mg·kg-1). To monitor general hematological health a blood sample was
obtained at every measurement time point by drawing 1 mL of blood from the
central ear artery, anticoagulated in K2E 7.2 mg EDTA BD Vacutainer® 4 mL
tubes (Becton, Dickinson & Co., Plymouth, United Kingdom) and analyzed by 4 an automated Sysmex XE-5000 (Sysmex Corporation, Kobe, Japan). Hereafter, microcirculation measurements and RT were performed. After all data
collection and RT atipamezole (Antisedan®, Pfizer Animal Health BV, Capelle aan den IJssel, The Netherlands; 1 mg·kg-1 sc) was administered to reverse anesthesia. At the end of the study the animals were sacrificed using sodium pentobarbital (Euthasol®, AST Farma BV, Oudewater, The Netherlands; 120 mg·kg-1 iv) administered via the lateral ear vein. After sacrifice the mandibles with overlaying mucosa were dissected and excised for postmortem histopathological analysis. All animals were exposed to the same experimental proceedings: weighing, sedation, baseline and consecutive weekly whole blood counts, microcirculation measurements, RT, reversal of anesthesia, sacrifice and mandibular excision.
Irradiation (IR)
IR was performed using an Xstrahl X-ray generator (Xstrahl Ltd., Surrey, United Kingdom), operated at 225 kV and 15 mA and inherent filtration with 1 mm Cu, a square tube collimator with an area of 8x8 cm2. After being anesthetized the fur on the right lower jaw was shaved, the right side of the mandible was marked and subsequently the animals were transported from their housing facility to the IR lab at the Department of Experimental RT. Upon arrival at the experimental RT lab each rabbit was placed in a dorsally recumbent position on a table-top under the X-ray generator. The mandible faced the focus source of
Onset of late irradiation effects
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