Authors : JR.L.H. Jales , A.M.O.Ramos , R.L.C.Jales , C.M.C.X.Holanda , P.L.J.Brito , R.D.Jales , L.H.Jalesneto , L.S.A.A. Viana , M.L. Teixeira , M.T.J. Catanho , R.C.H. Leite , L.M.L. Brito , K.C. Brand?o , L.F. Amorim and E.M. Bernardo-Filho
Abstract: The biodistribution of radiopharmaceutical used in diagnostic imaging can be altered by a wide variety of factors. There are some evidences that some drugs (natural or synthetic) can modify the bioavailability of. radiopharmaceutical. If unknown, the drug interaction with radiopharmaceuticals can lead to misdiagnosis or the necessity to repeat the examination, increasing the dose to the patient. The morphine is the main analgesic drug of the group of the opium and it has been used extensively in the medical field to treat severe pain, mainly those provoked by cancer. Many patients suffering of oncologic pain utilize the morphine as anthialgic therapy and need to submit themselves to complementary exams like bone scintigraphy which utilizes the methylenediphosphonic acid(MDP) labeled with 99m Technetium (99mTc-MDP) to evaluate the presence of metastasis. To evaluate the effects of the morphine on the biodistribution of 99mTc-MDP in male Wistar rats, morphine (30mg/Kg/day) was administered in male Wistar rats (n=6; age= 3 months old),orally, during 7 days. One hour after the last dose, were injected 0,1ml of 99Tc-MDP(100?Ci), via ophthalmic plexus. The control group (n=6) received only physiologic solution, instead of morphine, in the same conditions. The animals were rapidly sacrificed in 2 different periods: one group in 60 minutes (n= 6) and the other group in a 120 minutes (n=6) after administration the 99mTc-MDP. The various organs from the animals were isolated then, the radioactivity of the 99m Tc-MDP was counted and compared between the two groups : morphine treated and control. Statistical analysis were performed using the Wilcoxon test(P<0.05) The analysis of the results reveals a significant increase (p<0.05) of the uptake of radioactivity in the treated group at 60 minutes in lungs, heart , stout bowel, liver, spleen, kidneys, bladder, femoral muscles and femoral boneand a reduction in thyroid, stomach and pancreas. And in the group treated at 120minutes analysis of the results reveals a significant reduction (p<0.05) of the %ATI in lungs, heart, thyroid, stout bowel, liver, pancreas, spleen, kidneys, bladder, testis, femoral muscles and bone, on the other hand , results show a increase of the %ATI in stomach and duodenum. These results could be associated with the biological effects or/and metabolization of the morphine.
JR.L.H. Jales , A.M.O.Ramos , R.L.C.Jales , C.M.C.X.Holanda , P.L.J.Brito , R.D.Jales , L.H.Jalesneto , L.S.A.A. Viana , M.L. Teixeira , M.T.J. Catanho , R.C.H. Leite , L.M.L. Brito , K.C. Brand?o , L.F. Amorim and E.M. Bernardo-Filho , 2004. Influence of the Morphine on the Kinetic of Biodistribution of Technetium-99m Labeled with MDP in Wistar Rats . Journal of Animal and Veterinary Advances, 3: 306-310.