Table 2.
Summary of the main ultrastructural features of the subcellular and subsynaptic localization of mGluR subtypes in the basal ganglia, as revealed by high resolution pre-embedding immunogold procedures.
| Structure | Presynaptic | Postsynaptic | References | |||
|---|---|---|---|---|---|---|
| Intracellular | Membrane-bound | |||||
| Extrasynaptic | Perisynaptic | Synaptic | ||||
| Striatum | 1a (Thal, Ctx) | 1a | 1a | 1a (Glu) | 1a (GABA) | 1a, 5: Paquet and Smith, 2003 |
| 3 (Ctx) | 5 | 5 | 5 (Glu, DA) | 5 (GABA) | 3: Tamaru et al., 2001 | |
| 4 (Glu, GABA) | 4: Corti et al., 2002 | |||||
| GP | 4 (GABA) | 5 | 1a | 1a (Glu) | 1a (GABA) | 1a, 5: Hanson and Smith, 1999 |
| 5 | 5 (Glu) | 5 (GABA) | 4: Corti et al., 2002 | |||
| STN | - | 1a | 1a | 1a (Glu, GABA) | - | 1a, 5: Kuwajima et al., 2004b |
| 5 | 5 | 5 (Glu, GABA) | ||||
| SNr | 4 (Glu, GABA) | 5 | 1a | 1a (Glu) | 1a (GABA) | 1a, 5: Hubert et al., 2001 |
| 5 | 5 (Glu) | 5 (GABA) | 4: Corti et al., 2002 | |||
Source(s) of afferents and chemical phenotype of synapses are indicated in parentheses. Ctx– cortex; DA – dopamine; GABA – γ-aminobutyric acid; Glu – glutamate; Thal – thalamus.
In all basal ganglia, most of the plasma membrane-bound group I mGluRs is extrasynaptic.
No published data is available on the immunogold localization of mGluRs 2, 7, and 8 in all basal ganglia