Fig. 5
Inhibition of Gβγ-mediated GIRK signaling by Nb5. a Representative whole-cell recording of a GIRK2+ striatal medium spiny neuron (MSN) treated with 10 μM of intracellular Nb5. A single electrical stimulation evoked a D2R-IPSC that showed a significant amplitude reduction 15 min post-treatment with Nb5 (greencyan) as compared to the averaged trace observed at 5 min post-treatment with Nb5 (grey). b Representative trace of an M4-IPSC that displays an amplitude reduction 15 min post-treatment with Nb5 (greencyan) as compared to the averaged trace observed at 5 min post-treatment with Nb5 (grey). But no significant change was noted in D2R-IPSC either exposed to 10 μM intracellular Nb17 (c) or without nanobody treatment (d). Time course measurements showing a decrease in D2R-IPSC (e) and M4R-IPSC (f) amplitudes upon their exposure to 10 μM Nb5. Time course measurements of D2R-IPSC amplitudes recorded either with Nb17 (g) or without nanobody treatment (h). Bar graph quantification of D2R-IPSC (n = 9) (i) and M2R-IPSC (n = 8) (j) amplitudes recorded with Nb5. Bar graph quantification of D2R-IPSC amplitudes (n = 5) recorded either with 10 μM Nb17 (k) or without nanobody treatment (l), revealing no significant change in amplitudes over 15 min. Results are expressed as the mean ± SEM. *P < 0.05, Student’s t-test m Proposed model of GIRK inhibition by Nb5
