Physiological Assessment in Stroke Research - Animal Models of Acute Neurological Injuries: Injury and Mechanistic Assessments - page 81

5.1. ( 14 C)
Iodoantipyrine
Autoradiography

For a number of years, autoradiography was considered to be the
gold standard in cerebral blood fl ow measurement (with a spatial
resolution of ~100 m and a temporal resolution of 30 s). This is a

highly invasive technique that requires microsurgical skills and the
animal must be sacrifi ced immediately afterward to collect fl ow data.
Iodoantipyrine autoradiography was fi rst developed by Sakurada
et al. in 1979 ( 40 ). This technique utilizes the brain distribution of
( 14 C) iodoantipyrine as a blood fl ow indicator and results are dis-
played as coronal images along the rostro-caudal axis of the brain
(Fig. 1 ). Although designed for blood fl ow analysis, this technique
allows for blood pressure measurements and blood sampling at dif-
ferent time points while the catheter is still inserted. For a detailed
technical description of this method, please refer to ref. ( 41 ).
Technique
Appropriately anesthetize the animals

μ

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Monitor animals for signs of pain, distress, and infections

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throughout the procedure. Control for body temperature
Insert a polyethylene tubing catheter (PE 10 for mice and PE 50

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for rats) approximately 3 cm into the femoral artery and vein
Infuse 10 mCi of (

14 C) iodoantipyrine into the femoral vein
over 20-30 s. During these 20 s (mice) or 30 s (rats), collect
six timed blood samples for blood radioactivity measurement

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Fig. 1. Blood fl ow measurements using the ( 14 C) iodoantipyrine autoradiography method to
test the effects of pentobarbital on local cerebral blood fl ow. Coronal sections of a control
brain ( a ) and a brain treated with pentobarbital ( b ). Pentobarbital reduces ( 14 C) iodoantipy-
rine signal indicating a drop in local cerebral blood fl ow (Wei et al.; unpublished data).