Organ | Subtype of α2-AR | References | |
---|---|---|---|
Periphery | Spleen | α2C 3-a | Elenkov and Vizi, 1991 |
Thymus | α2C 3-a | Hasko et al., 1995b | |
Ileum | α2C 3-a | Blandizzi et al., 1993 | |
Central nervous system | Cortex | α2A | Trendelenburg et al., 1996 |
Hippocampus | α2A | Kiss et al., 1995 | |
Spinal cord | α2A | Umeda et al., 1997 |
↵3-a Earlier it was designated as α2B-ARs, because prazosin increased the release of NE, but it has recently been shown that prazosin is an α1 and α2B/C antagonist (cf. Docherty, 1998), and it was shown, using gene substitution/knockout mice, that α2B-ARs are located postsynaptically (cf. Hein et al., 1998). Therefore it seems very likely that the α2C-subtype of presynaptic α2-ARs is involved in the negative feedback modulation of NE release.