Abstract
99mTc-hexamethylpropyleneamineoxime (99mTc-HMPAO) is a reagent for scanning cerebral blood flow. We investigated how99mTc-HMPAO changed in the blood and brain. The99mTc-HMPAO, which was prepared by adding of99mTcO 4- to HMPAO and Sn(II), consisted of primary and secondary complexes, reduced hydrolyzed99mTc, and99mTc0pertechnetate. The percentage of the primary complex in99mTc-HMPAO decreased with time after preparation. The primary complex converted to the secondary one very rapidly in the presence of plasma. When99mTc-HMPAO was injected into patients,99mTc activity was immediately partitioned in the plasma fraction, with approximately 60% in whole blood. In plasma,99mTc was found to be associated with proteins such as albumin and globulin.99mTc trapped in red cells was not washed out with either plasma or saline. Biodistribution studies showed that the less lipophilic compounds of99mTc-HMPAO could not pass through the blood brain barrier (BBB), and therefore did not accumulate in the brain. The results of gel chromatography and equilibrium dialysis indicated that no specific99mTc binding protein was present in the brain. Considering the instability of99mTc-HMPAO in vivo, we proposed that the speed at which the primary complex converted to the less lipophilic compounds was important in allowing99mTc-HMPAO to pass through the BBB and to be fixed in the brain.
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References
Canning LR, Nechvatal G, Cumming SA, Nowotnik DP, Pickett RD, Piper IM, Neirinckx RD, Volkert WA, Troutner DE, Holmes RA (1986)99mTc-Hexamethyl-porpyleneamineoxime (99mTc-HMPAO): A new radiopharmaceutical for rCBF imaging. Nuklearmedizin 22:173–175 [Suppl]
Costa DC, Ell PJ, Cullum ID, Jarritt PH (1986) The in vivo distribution of99mTc in normal man. Nucl Med Commun 7:647–658
Ell PJ, Hocknell JML, Costa DC, Jarritt PH, Cullum ID, Lui D, Nowotnik DP, Pickett RD, Neirinckx RD, Jewkes RF, Steiner TJ, Jones B (1986)99mTc-Hexamethyl-propyleneamineoxime (99mTc-HMPAO): A breakthrough in radionuclide CBF tomography. Nuklearmedizin 22:179–181 [Suppl]
Gemmell HG, Sharp PF, Besson JAO, Crawford JR, Ebmeier KP, Davidson J, Smith FW (1987) Differential diagnosis in dementia using the cerebral blood flow agent99mTc-HMPAO: A SPECT study. J Comput Assist Tomogr 11:398–402
Hammersley PAG, McCready VR, Babich JW, Coghlan G (1987)99mTc-HMPAO as a tumor blood flow agent. Eur J Nucl Med 13:90–94
Hill TC, Holman BL, Lovett R, O'Leary DH, Fronbt D, Magistretti P, Zimmerman RE, Moore S, Clousen ME, Wu JL, Lin TH, Baldwin RM (1982) Initial experience with SPECT (Single-Photon Computerized Tomography) of the brain using N-isopropyl I-123-iodoamphetamine. Concise Communication. J Nucl Med 23:191–195
Neirinckx RD, Channing LR, Piper IM, Nowotonik DP, Pickett RD, Holmes RA, Volkert WA, Forster AM, Weisner PS, Marriott JA, Chaplin SB (1987a) Technetium 99m d,l-HMPAO: A new radiopharmaceutical for SPECT imaging of regional cerebral blood perfusion. J Nucl Med 28:191–202
Neirinckx RD, Harrison RC, Forster AM, Burke JF, Anderson AR, Lassen NA (1987b) A model for the in-vivo behaviour of Tc-99m d,l-HMPAO in man (abstr.). J Nucl Med 28:559
Podreka I, Suess E, Goldenberg G, Steiner M, Brucke T, Muller C, Lang W, Neirinckx RD, Deecle L (1987) Initial experience with technetium-99m HMPAO brain SPECT. J Nucl Med 28:1657–1666
Sharp PF, Smith FW, Gemmell HG, Lyall D, Evans NTS, Gvozdanovic D, Davidson J, Tyrrell DA, Pickett RD, Neirinckx RD (1986) Technetium-99m HMPAO stereoisomers as potential agents for imaging regional cerebral blood flow: Human volunteer studies. J Nucl Med 27:171–177
Spreafico G, Cammelli F, Gadola G, Nicola G, Zancamer F, Tonnearelli G, Sala E, Freschi R (1987) Initial experience with SPECT of the brain using99mTc-hexamethyl-propyleneamineoxime (99mTc-HMPAO). Eur J Nucl Med 12:557–559
Tukatani Y, Nakamura K, Fujii H, Kuneida E, Ogawa K, Kubo A, Hashimoto S, Terayama Y, Amano T, Goto F, Sanmiya T, Shimizu S, Sakurada (1988) Basic and clinical evaluation on regional cerebral perfusion scintigraphy of Tc-99m-HMPO. Jpn J Clin Radiol 33:743–749
Volkert WA, Hoffmann TJ, Seger RM, Troutner DE, Holmes RA (1984)99mTc-propylene amine oxime (99mTc-PnO); a potential brain radiopharmaceutical. Eur J Nucl Med 9:511–516
Yeh SH, Liu RS, Hu HH, Wong WJ, Lo YK, Lai ZY, Huang JC, Chang SL, Wang SJ, Chu FL (1986) Brain SPECT imaging with99mTc-hexamethylpropyleneamine oxime in the early detection of cerebral infarction. Comparison with trausmission computed tomography. Nucl Med Commun 7:873–878
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Nakamura, K., Tukatani, Y., Kubo, A. et al. The behavior of99mTc-hexamethylpropyleneamineoxime (99mTc-HMPAO) in blood and brain. Eur J Nucl Med 15, 100–107 (1989). https://doi.org/10.1007/BF00702628
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DOI: https://doi.org/10.1007/BF00702628