Ac. Mackinnon et al., ALPHA(2)-ADRENOCEPTORS - MORE SUBTYPES BUT FEWER FUNCTIONAL DIFFERENCES, Trends in pharmacological sciences, 15(4), 1994, pp. 119-123
The proliferation of receptor subtypes based on differences in amino a
cid sequence does not necessarily coincide with functional differences
. The number of alpha(2)-adrenoceptor subtypes, as defined by ligand-b
inding and molecular studies, has been increasing in the past few year
s, which suggests the possibility of distinct physiological and pathol
ogical pathways that could be targeted by new selective drugs. However
, the evidence from functional studies has been less convincing. This
could be due to the lack of sufficiently selective ligands or to the s
imilarity between the activated state of receptor subtypes. Species di
fferences and the local receptor environment are also important determ
inants of the pharmacological profile of a particular subtype. The pha
rmacology of the putative subtypes of alpha(2)-adrenoceptors and their
function ave discussed in this review by Alison MacKinnon, Mike Spedd
ing and Christine Brown.