Influence of age on norepinephrine content in arteries and veins of Fischer 344 rats.
The norepinephrine content of blood vessels in male Fischer 344 rats aged 6, 12, 20 and 27 months was measured by electrochemical detection after alumina extraction and high-performance liquid chromatography separation. With the exception of the superior mesenteric artery which showed no age-related changes in norepinephrine content and the caudal artery which showed an increase from 12 to 27 months of age, all other arteries examined (renal, femoral, saphenous, superficial epigastric, and popliteal) showed a significant decline in norepinephrine content with advancing age. In contrast, the content of norepinephrine in the renal, femoral, saphenous and superior mesenteric veins remained constant at all ages. Since norepinephrine in the blood vessel wall is predominantly localized to sympathetic nerve endings, the decline in norepinephrine content in most arteries of old rats may reflect a selective decrease in the density of sympathetic neurons or alternatively an age-related alteration in the metabolic properties of these sympathetic nerve endings.
Handa
R K
RK
Department of Pharmacology, College of Medicine, University of California, Irvine 92717.
Duckles
S P
SP
D000375:Aging / Q000378:metabolism*; D000818:Animals; D001158:Arteries / Q000378:metabolism*; D008297:Male; D009638:Norepinephrine / Q000378:metabolism*; D051381:Rats; D011916:Rats, Inbred F344; D014680:Veins / Q000378:metabolism*
D009638:Norepinephrine