Identification of angiotensin II receptor subtypes in human brain.
The present study assessed the binding characteristics of [125I]angiotensin II to slices of human cerebellum adhered to glass slides using quantitative receptor autoradiography. Specific [125I]angiotensin II binding, defined by the inclusion of unlabelled angiotensin II (1.0 microM), was detected in the molecular layer of the cerebellum (0.09 +/- 0.02 fmol/mg tissue equivalent, mean +/- s.e.m., n = 3). The angiotensin II-2 receptor subtype selective ligand, PD123177, competed for approximately 65% of the specific binding in the molecular layer whilst the remainder of the specific binding was displaced by the angiotensin II-1 receptor subtype selective ligand, DuP753. It is concluded that angiotensin II receptor subtypes exist in human brain tissue and provide potential therapeutic sites of action.
Barnes
J M
JM
Department of Pharmacology, Medical School, University of Birmingham, Edgbaston, UK.
Barber
P C
PC
Barnes
N M
NM
D000368:Aged; D000804:Angiotensin II / Q000037:antagonists & inhibitors / Q000378:metabolism*; D057911:Angiotensin Receptor Antagonists; D001345:Autoradiography; D001667:Binding, Competitive; D001713:Biphenyl Compounds / Q000494:pharmacology; D002531:Cerebellum / Q000166:cytology / Q000378:metabolism*; D005260:Female; D006801:Humans; D007093:Imidazoles / Q000494:pharmacology; D007457:Iodine Radioisotopes; D019808:Losartan; D008297:Male; D011725:Pyridines / Q000494:pharmacology; D011945:Receptors, Angiotensin / Q000032:analysis / Q000378:metabolism*; D013777:Tetrazoles / Q000494:pharmacology
D057911:Angiotensin Receptor Antagonists; D001713:Biphenyl Compounds; D007093:Imidazoles; D007457:Iodine Radioisotopes; D011725:Pyridines; D011945:Receptors, Angiotensin; D013777:Tetrazoles; D000804:Angiotensin II; C066253:PD 123177; D019808:Losartan