Cystic adventitial disease of the popliteal artery is an uncommon disorder. 58-year-old male complained of left intermittent calf claudication and couldn't sit straight. He preferred playing baseball and jogging. Digital subtraction angiograms revealed a smooth extrinsic compression on the proximal left popliteal artery. Surgical procedure was performed with posterior approach. The left popliteal artery was confirmed to be surrounded by two adventitial cysts at operation. After the evacuation and removal of these cystic wall, peripheral popliteal artery pulse was improved. Postoperative course was smooth and calf claudication was completely disappeared, post operative angiogram showed no stenosis. Histological examination of the resected specimen showed degenerated elastic fiber and inflammatory granulation. We have found 40 cases previously reported in Japan and the present case was 2nd one in our institute.

OBJECTIVECadmium is known to affect the vascular tone of isolated blood vesselsin vitro and the arterial pressure of ratsin vivo. However, the mechanisms of cadmium actions on the vascular system have not been clarified. To elucidate the actions of cadmium on vascular tonus, effects of cadmium on vasocontractile and vasorelaxant responsesin vitro were investigated using aortic strips isolated from rats.

METHODSAortic strips isolated from male Wistar rats were incubated with CdCl(2) (10μM) for 24 hr, washed with fresh CdCl(2)-free medium, and then used for measurement of isometric tension and Western blot analysis of eNOS (endothelial nitric oxide synthase) and iNOS (inducible nitric oxide synthase).

RESULTSIn the aortas pretreated with cadmiumin vitro, the contractile response to phenylephrine was significantly higher than that in the control aortic strips pretreated with a vehicle. The sodium nitroprusside-induced relaxing response was significantly higher in the aortic strips pretreated with cadmium for 24 hr, compared with that in the control pretreated with a vehicle. The isoproterenol-induced relaxing response was also significantly higher in the cadmium-accumulated aortic strips.In vitro cadmium treatment slightly but not significantly increased the acetylcholine-induced relaxation of the aortic strips. Cadmium treatment induced expression of iNOS and significantly increased expression of eNOS in the aortic strips, while it did not affect expression of β-actin.

CONCLUSIONSCadmium treatmentin vitro augmented the α1 adrenoceptor-mediated contractile response, even though eNOS and iNOS were upregulated by cadmium treatment. NO-induced and β-adrenoceptor-mediated relaxing responses were also augmented by cadmium treatment. These results suggest that both vasocontractile and vasorelaxing responses are augmented in cadmium-accumulated aortas.