The potential of ^99mTc labeled P^1, P^4-di （adenosine-5 ＇ ）-tetraphosphate （Ap4A） for imaging experimental atherosclerotic plaques was evaluated in New Zealand white （NZW） rabbits. To label the ^99mTc to Ap4A,...The potential of ^99mTc labeled P^1, P^4-di （adenosine-5 ＇ ）-tetraphosphate （Ap4A） for imaging experimental atherosclerotic plaques was evaluated in New Zealand white （NZW） rabbits. To label the ^99mTc to Ap4A, stannous tartrate solution was used. ^99mTc-Ap4A was purified on a Sephadex G-25 column. The radiochemistry purities of ^99mTc-Ap4A were 85% to 91%. Biodistribution study revealed ^99mTc-Ap4A cleared from blood rapidly. Thirty min after ^99mTc-Ap4A administrated on NZW atherosclerotic rabbits, lesion to blood （target/blood, T/B） ratio was 3. 17 ±1.27, and lesions to normal （target/non-target, T/NT） ratio was 5.23 ±1.87. Shadows of atherosclerotic plaques were clearly visible on radioautographic film. Aortas with atherosclerotic plaques also could be seen on ex vivo gamma camera images. Atherosclerotic abdominal aortas were clearly visible on in vivo images 15 min to 3 h after ^99mTc-Ap4A administration. ^99mTc-labeled Ap4A can be used for rapid noninvasive detection of experimental atherosclerotic plaque.展开更多
The proliferationof vascular smooth muscle cells (VSMC) plays a role in the maintenance of hypertension and atherosclerosis. Diadenosine polyphosphates have been identified as modulators of the cardiovascular system. ...The proliferationof vascular smooth muscle cells (VSMC) plays a role in the maintenance of hypertension and atherosclerosis. Diadenosine polyphosphates have been identified as modulators of the cardiovascular system. We detected the existence of diadenosine polyphosphates in the heart and studied their growth stimulating effect on VSMC. Porcine cardiac tissue was deproteinated with perchloric acid and concentrated with a preparative reversed phase C18 column. Then the extract was separated with a size exclusion column, an anion exchange column, and an affinity column. It was then chromatographed with an anion exchange HPLC and a reversed phase HPLC and a purified substance was obtained. Med. Klinik I, Nephrol. Labor, Univ. Klinik Marien hospital, University of Bochum, Herne, Germany (Luo JK, Wang H, Schlüter H, JankowskifJ, Potthoff W, Tepel M and Zidek W) Using the BrdU method, this substance was shown to have a growth stimulating effect that is dose-dependent on VSMC. Matrix assisted laser desorption/ionization mass spectrometry (MALDI MS) analysis showed that the molecular mass of the substance was 757.0, the same as diadenosine triphosphate (AP 3A). UV spectrum indicated the maximum absorption at 259 nm, similar to that of adenosine. Postsource decay (PSD) MALDI MS showed that the substance contained adenine, adenosine, AMP, ADP, and ATP, respectively. Enzymatic cleavage revealed that phosphates in this molecule connected adenosine in 5' position. It was determined from the above data that the substance was Ap 3A. In this study the existence of Ap 3A was demonstrated in the heart. It has a growth stimulating effect on VSMC.展开更多
文摘The potential of ^99mTc labeled P^1, P^4-di （adenosine-5 ＇ ）-tetraphosphate （Ap4A） for imaging experimental atherosclerotic plaques was evaluated in New Zealand white （NZW） rabbits. To label the ^99mTc to Ap4A, stannous tartrate solution was used. ^99mTc-Ap4A was purified on a Sephadex G-25 column. The radiochemistry purities of ^99mTc-Ap4A were 85% to 91%. Biodistribution study revealed ^99mTc-Ap4A cleared from blood rapidly. Thirty min after ^99mTc-Ap4A administrated on NZW atherosclerotic rabbits, lesion to blood （target/blood, T/B） ratio was 3. 17 ±1.27, and lesions to normal （target/non-target, T/NT） ratio was 5.23 ±1.87. Shadows of atherosclerotic plaques were clearly visible on radioautographic film. Aortas with atherosclerotic plaques also could be seen on ex vivo gamma camera images. Atherosclerotic abdominal aortas were clearly visible on in vivo images 15 min to 3 h after ^99mTc-Ap4A administration. ^99mTc-labeled Ap4A can be used for rapid noninvasive detection of experimental atherosclerotic plaque.
文摘The proliferationof vascular smooth muscle cells (VSMC) plays a role in the maintenance of hypertension and atherosclerosis. Diadenosine polyphosphates have been identified as modulators of the cardiovascular system. We detected the existence of diadenosine polyphosphates in the heart and studied their growth stimulating effect on VSMC. Porcine cardiac tissue was deproteinated with perchloric acid and concentrated with a preparative reversed phase C18 column. Then the extract was separated with a size exclusion column, an anion exchange column, and an affinity column. It was then chromatographed with an anion exchange HPLC and a reversed phase HPLC and a purified substance was obtained. Med. Klinik I, Nephrol. Labor, Univ. Klinik Marien hospital, University of Bochum, Herne, Germany (Luo JK, Wang H, Schlüter H, JankowskifJ, Potthoff W, Tepel M and Zidek W) Using the BrdU method, this substance was shown to have a growth stimulating effect that is dose-dependent on VSMC. Matrix assisted laser desorption/ionization mass spectrometry (MALDI MS) analysis showed that the molecular mass of the substance was 757.0, the same as diadenosine triphosphate (AP 3A). UV spectrum indicated the maximum absorption at 259 nm, similar to that of adenosine. Postsource decay (PSD) MALDI MS showed that the substance contained adenine, adenosine, AMP, ADP, and ATP, respectively. Enzymatic cleavage revealed that phosphates in this molecule connected adenosine in 5' position. It was determined from the above data that the substance was Ap 3A. In this study the existence of Ap 3A was demonstrated in the heart. It has a growth stimulating effect on VSMC.
