PROKR2 and Alzheimer disease: In the animal model of AD, induced by intracerebroventricular (i.c.v.)injection of the b amyloid peptide toxic fragment 1–42 (Aβ1–42) n the rat, this PKR2 splice variant is strongly upregulated, leading to an increase in the expression ratio between TM 4-7/PKR2 in the rat hippocampus [23].