DECREASE IN PREPRO-NEUROPEPTIDE-Y GENE-EXPRESSION IN THE ADRENAL-GLAND AND CEREBRAL-CORTEX OF SPONTANEOUSLY HYPERTENSIVE RATS

Changes in the mRNA and peptide levels of neuropeptide Y (NPY) in the adrenal gland and brain areas of spontaneously hypertensive rats (SHR) and of age-matched normotensive rats were investigated. The level of adrenal NPY mRNA of SHR decreased during progression of hypertension a nd was lower than that of Wistar-Kyoto (WKY) and Sprague-Dawley (SD) r ats in the early stage of hypertension, while the level of adrenal NPY was unchanged or even higher than that of control rats. These finding s suggest that both the biosynthesis and release of vasoconstrictive N PY peptide in the adrenal glands of SHR might decrease during progress ion of hypertension. In contrast, the NPY mRNA level neither decreased remarkably until week 17 in the cerebral cortex of SHR, nor changed a t all in the other brain areas, This late decrease in cerebral NPY gen e expression might be related to the disturbance in behavior and memor y of SHR.