Percentage of BDA-labeled IT-type versus PT-type terminals making axospinous synaptic contact with striatonigral versus striato-GP neurons, as identified by dopamine receptor immunolabeling
| Type of spine targeted by BDA + synaptic terminal | Percentage of BDA + IT-type terminal synapsing on given spine type | Percentage of BDA + PT-type terminal synapsing on given spine type | Significance of IT-type versus PT-type frequency difference by t test | Mean ± SEM size of BDA + IT-type axospinous synaptic terminal | Mean ± SEM size of BDA + PT-type axospinous synaptic terminal | Significance of IT-type versus PT-type size difference by t test |
|---|---|---|---|---|---|---|
| D1 + (striatonigral) | 50.9% (based on 75 BDA + IT-type synaptic terminals on D1 + spines in six striata) | 21.3% (based on 39 BDA + PT-type synaptic terminals on D1 + spines in seven striata) | IT versus PT frequency on D1 + spines significantly different at p = 0.008 | 0.40 ± 0.016 μm (n = 6 striata) | 0.68 ± 0.077 μm (n = 5 striata) | IT versus PT size significantly different on D1 + spines at p = 0.002 |
| D2 + (striato-GP) | 12.6% (based on 29 BDA + IT-type synaptic terminals on D2 + spines in five striata) | 50.5% (based on 68 BDA + PT-type synaptic terminals on D2 + spines in five striata) | IT versus PT frequency on D2 + spines significantly different at p = 0.0003 | 0.43 ± 0.057 μm (n = 3 striata) | 0.72 ± 0.041 μm (n = 5 striata) | IT versus PT size significantly different on D2 + spines at p = 0.003 |
| Significance of D1 versus D2 difference by t test | D1 versus D2 frequency of IT synaptic input significantly different at p = 0.002 | D1 versus D2 frequency of PT synaptic input significantly different at p = 0.005 | IT-type size not significantly different; p = 0.391 | PT-type size not significantly different; p = 0.578 |