The ACE inhibitor [3H]SQ29,852 identifies a high affinity recognition site located in the human temporal cortex.
The angiotensin converting enzyme (ACE) inhibitor [3H]SQ29,852 identified a single high affinity recognition site (defined by 10.0 microM captopril) in the human temporal cortex (pKD 8.62 +/- 0.03; Bmax 248 +/- 24 fmol mg-1 protein, mean +/- S.E.M., n = 4). ACE inhibitors and thiorphan competed to a similar level for the [3H]SQ29,852 binding site in the human temporal cortex with a rank order of affinity (pKi values mean +/- S.E.M., n = 3), lisinopril (9.49 +/- 0.02), captopril (9.16 +/- 0.08), SQ29,852 (8.58 +/- 0.04), epicaptopril (7.09 +/- 0.08), fosinopril (7.08 +/- 0.05) and thiorphan (6.40 +/- 0.04). Since this rank order of affinity is similar to the affinity of these compounds to inhibit brain ACE activity it is concluded that [3H]SQ29,852 selectively labels the inhibitor recognition site of ACE in the human temporal cortex.
School of Pharmacy, University of Bradford, West Yorkshire, UK.
N M
NM
Barnes
B
B
Costall
P
P
Egli
Z P
ZP
Horovitz
J W
JW
Ironside
R J
RJ
Naylor
T J
TJ
Williams
D000328:Adult; D000368:Aged; D000806:Angiotensin-Converting Enzyme Inhibitors / Q000494:pharmacology*; D001665:Binding Sites / Q000187:drug effects*; D002540:Cerebral Cortex / Q000187:drug effects / Q000378:metabolism*; D006801:Humans; D066298:In Vitro Techniques; D007457:Iodine Radioisotopes; D007700:Kinetics; D008297:Male; D008875:Middle Aged; D009943:Organophosphorus Compounds / Q000494:pharmacology*; D011392:Proline / Q000031:analogs & derivatives* / Q000494:pharmacology; D013702:Temporal Lobe / Q000187:drug effects / Q000378:metabolism*
D000806:Angiotensin-Converting Enzyme Inhibitors; D007457:Iodine Radioisotopes; D009943:Organophosphorus Compounds; D011392:Proline; C054518:ceronapril