Table 1.
Astrocyte modulation of presynaptic terminals and GABAAR clusters
|
|
Number of SP boutons (per 20 μm segment) |
Number of VGAT boutons (per 20 μm segment) |
Number of VGLUT boutons (per 20 μm segment) |
Number of GABAAR clusters (per 20 μm segment) |
Percentage of GR colocalization with SP + boutons |
|---|---|---|---|---|---|
| 4 div | |||||
| Pure neuronal cultures | 2.0 ± 0.4 (55) | 0.8 ± 0.1 (88) | 1.7 ± 0.2 (42) | 1.9 ± 0.2 (38) | 0.5 ± 0.2 |
| Astrocyte cocultures | 7.9 ± 0.5 (58)** | 5.4 ± 0.6 (85)** | 4.6 ± 0.5 (46)** | 4.2 ± 0.2 (32)** | 13.3 ± 0.9** |
| ACM-treated cultures | 7.9 ± 0.8 (52)** | 5.1 ± 0.4 (87) | 4.3 ± 0.6 (47)* | 3.9 ± 0.3 (35)* | 13.7 ± 0.7** |
| FCM-treated cultures | 2.2 ± 0.5 (25) | 1.1 ± 0.3 (25) | n.d. | 2.4 ± 0.3 (25) | 0.8 ± 0.6 |
| 7 div | |||||
| Pure neuronal cultures | 4.8 ± 0.3 (55) | 2.0 ± 0.40 (68) | 4.0 ± 0.7 (53) | 2.2 ± 0.2 (35) | 6.0 ± 0.5 |
| Astrocyte cocultures | 9.7 ± 0.6 (55)** | 7.9 ± 0.7 (60)** | 7.2 ± 0.4 (52)* | 4.9 ± 0.3 (35)** | 31.9 ± 2.3** |
| ACM-treated cultures | 9.1 ± 0.4 (55)** | 8.3 ± 0.8 (60)** | 8.5 ± 0.6 (52)** | 4.8 ± 0.2 (38)** | 36.7 ± 1.1** |
| FCM-treated cultures | 4.4 ± 1.0 (25) | 2.1 ± 0.3 (25) | n.d. | 3.2 ± 0.6 (25) | 8.6 ± 2.2 |
| 10 div | |||||
| Pure neuronal cultures | 6.8 ± 0.6 (42) | 3.8 ± 0.4 (50) | 5.8 ± 0.4 (25) | 3.4 ± 0.2 (35) | 10.1 ± 1.0 |
| Astrocyte cocultures | 13.4 ± 0.5 (36)** | 11.2 ± 0.9 (42)** | 8.9 ± 0.6 (25)* | 8.0 ± 0.5 (36)** | 39.1 ± 3.9** |
| ACM-treated cultures | 12.8 ± 0.6 (41)** | 9.3 ± 0.9 (48)** | 10.2 ± 0.5 (25)** | 8.4 ± 0.2 (34)** | 37.1 ± 2.9** |
| FCM-treated cultures | 6.5 ± 0.8 (25) | 2.3 ± 0.6 (25) | n.d. | 4.6 ± 0.8 (25) | 11.0 ± 2.9 |
|
|
Number of SP boutons (per 20 μm segment) |
Number of VGAT boutons (per 20 μm segment) |
Number of VGLUT boutons (per 20 μm segment) |
Number of GABAAR cluster (per 20 μm segment) |
Percentage of GR colocalization with VGAT + boutons |
|---|---|---|---|---|---|
| 10 div | |||||
| Pure neuronal cultures | 1.3 ± 0.2 (15) | 0.7 ± 0.2 (15) | n.d. | 2.4 ± 0.3 (15) | 3.8 ± 1.9 |
| Cholesterol-treated cultures | 1.7 ± 0.2 (18) | 0.9 ± 0.2 (18) | n.d. | 2.2 ± 0.2 (18) | 1.8 ± 0.2 |
| ACM-treated cultures |
2.7 ± 0.4T (12)***
|
1.4 ± 0.3 (12)***
|
n.d. |
3.4 ± 0.4 (12) |
14.7 ± 4.0***
|
Values are shown as mean ± SEM (number of cells from 3-6 separate experiments). In the three experiments at 4, 7, and 10 div, neurons were treated with ACM using a feeder layer of astrocytes on a membrane inverted in the culture well. In the fȯurth experiment at 10 div, ACM collected from purified astrocyte monolayers was added directly to neuronal cultures, and feeder layers were not used (for details, see Materials and Methods). In all experiments, cluster number was compared among conditions using Kruskal-Wallis ANOVA followed by Dunn's pairwise multiple-comparison test. The percentage of presynaptic and postsynaptic colocalization among cultures was compared using Student's t test. *p < 0.001, **p < 0.0001, and ***p < 0.05, significantly different from pure neuronal cultures. n.d., Not determined.