Penttilä H, M.D., Huttunen P, M.Sc., von Smitten K, M.D., Ph.D., Ashammakhi N, M.D., Ph.D., FRCSEd., Waris T, M.D., Ph.D.

Abstract
To investigate the changes in noradrenaline concentrations in transplanted arterial grafts in rats, thirty-one four- to six-week-old female rats of AO/Ks:OC strain were operated on. Femoral arterial grafts were anastomosed to carotid arteries and compared with control femoral segments. Six rats were included in each follow-up group at 0, 1, 4 and 12 weeks and there were seven rats in the 20-week follow-up group. High-performance liquid chromatography (HPLC) was used to determine the concentrations of noradrenaline. The operation itself decreased noradrenaline concentrations in the grafts to 76% of that in control segments. One week after the operation the noradrenaline concentration had fallen to 1.7% of control and it started to recover thereafter. One month after the operation it was 23%, at three months 31% and at five months 43% of control values. The decrease from time 0 to one week was significant (p=0.001), as was the increase from one week to 20 weeks (p=0.004). Noradrenaline concentrations had fallen significantly one week after the operation and thereafter they rose to levels comparable to those seen in the immediate postoperative period.

Keywords: Arterial grafts, adrenergic nerves, noradrenaline, regeneration, reinnervation.