Tina software v 2

The aortas were excised, frozen in cooled isopentane, and sliced into serial longitudinal cryosections of 8 and 20 µm; then the accumulation of [⁶⁸Ga]Ga-DOTA-TCTP-1 in different areas of the aorta was analyzed by autoradiography. Air-dried sections were opposed to an imaging plate (Fuji Imaging Plate BAS-TR2025, Fuji Photo Film Co., Tokyo, Japan). After more than two radionuclide half-lives, the plates were scanned with a Fuji BAS-5000 analyzer (Fuji, Tokyo, Japan; internal resolution of 25 μm). Tracer accumulation was measured as counts per area (photostimulated luminescence per square millimeter, PSL/mm²) using TINA software v. 2.1 (Raytest Isotopenmessgeräte, GmbH, Straubenhardt, Germany). After careful co-registration of autoradiography and histological images, regions of interest (ROIs) defining plaque lesions, vessel wall, and adventitia were created. Background area count densities were subtracted from the image data. Uptake in the autoradiographs was normalized using a mathematical algorithm taking into account the radionuclide decay, injected radioactivity dose, time from injection to imaging plate exposure, and exposure time. Accumulation was measured primarily from 20 µm sections, with a comparison with immunohistochemistry being performed using the adjacent 8 µm sections.

A subgroup of MI rats (n = 3) were further analyzed to determine the microscopic distribution of the ⁶⁸Ga-DOTA at 30 minutes post-injection of the tracer. The LV was frozen in cooled isopentane and sliced into serial transverse cryosections of 8 and 20 μm at 1 mm intervals (five to six intervals per heart) from apex to base. Distribution of ⁶⁸Ga-DOTA in the infarcted and remote myocardium was analyzed by autoradiography of tissue sections. Air-dried sections were apposed to an imaging plate (BAS-TR2025; Fuji Photo Film Co. Tokyo, Japan), and after more than two radionuclide half-lives, the plates were scanned with a Fuji BAS-5000 analyzer (internal resolution of 25 μm). Tracer accumulation was measured as counts per area (photostimulated luminescence per square millimeter, PSL/mm²) with TINA software v.2.1 (Raytest Isotopenmessgeräte, GmbH, Straubenhardt, Germany).
After co-registration of autoradiography and histological images, ROIs were defined in the infarcted and remote areas of the LV. The background area count densities were subtracted from the image data. After autoradiography, the serial LV cryosections were stained with hematoxylin-eosin (HE) for histology.