Skip to main content
. Author manuscript; available in PMC: 2023 Oct 23.
Published in final edited form as: Cell Rep. 2023 Mar 22;42(4):112283. doi: 10.1016/j.celrep.2023.112283

Figure 4. PLC-PKCδ signaling is critically involved in pruritogen-induced sensitization of mechanosensitive pruriceptors and mechanical itch.

Figure 4.

(A) Representative whole-cell MA current traces elicited by mechanical indentation on DRG neurons isolated from MrgprA3Cre; Ai9f/f mice perfused with vehicle, histamine, or CQ, respectively.

(B) Summarized data of the current density of mechanosensitive MrgprA3+ neurons in response to vehicle (n = 11), histamine (n = 9), and CQ (n = 6).

(C and D) Histamine-induced (C) and CQ-induced (D) alloknesis scores in mice treated with vehicle or PLC inhibitor U73122. n = 5 mice for each group in (C), n = 11 vehicle-treated and n = 12 U73122-treated mice in (D).

(E) m-3M3FBS-induced alloknesis score in WT mice. n = 6 for vehicle-treated and n = 7 for m-3M3FBS-treated mice.

(F) Current density of whole-cell MA currents in the presence of vehicle and 1 μM m-3M3FBS in neurons isolated from MrgprA3Cre;Ai9f/f mice.

(G) Bar graph summarized the percentage of mechanosensitive DRG neurons in presence of vehicle and 1 μM m-3M3FBS.

(H) Representative images of MrgprA3 mRNA transcripts (red) and p-PKC (green) staining in DRG neurons isolated from WT mice treated with vehicle, histamine,U73122 + histamine, and gallein + histamine, respectively. Scale bar, 50 μm.

(I) Quantification of the number of p-PKC-expressing cells in MrgprA3+ neurons in response to different treatments in (H). n = 3–5 sections from 3 mice for each group.

(J) Representative images of MrgprA3 mRNA transcripts (red) and p-PKC (green) staining in DRG neurons isolated from WT mice treated with vehicle, CQ,U73122 + CQ, and gallein + CQ, respectively. Scale bar, 50 μm.

(K) Quantification of the number of p-PKC-expressing cells in MrgprA3+ neurons in response to different treatments in (J). n = 3–5 sections from 3 mice for each group. All scale bars, 100 μm.

(L and M) Histamine-induced acute chemical itch (L) and mechanical itch (M) in Cre− (n = 5) and Cre+ (n = 4) MrgprA3Cre; PKCdf/f mice.

(N and O) CQ-induced acute chemical itch (N) and mechanical itch (O) in Cre− (n = 5) and Cre+ (n = 4) MrgprA3Cre; PKCδf/f mice.

Data are expressed as mean ± SEM. n.s, not significant. *p < 0.05, **p < 0.01, ***p < 0.001, ****p < 0.0001, ##p < 0.01, ####p < 0.0001. Unpaired two-tailed Student’s t test in (C)–(F) and (L)–(O), chi-squared test for (G), and one-way ANOVA in (B), (I), and (K).