Figure 3.

Comparison of the number of patients expressing transcripts of G protein coupled receptor kinase (GRK), protein LIN-7 (LIN7) homologs, and 5-HT₄ or 5-HT₇ receptor splice variants in the mucosal (A), circular muscle (B), and longitudinal muscle (C) layers in tissue samples obtained from throughout the human colon (n = 16-18). Data are expressed as the number of patients where transcripts were detected. 5-HT₄ receptor d and g splice variants in mucosa and longitudinal muscle, GRK5 and GRK6 (all tissue layers) were detected at significantly lower frequencies than 5-HT₇ or 5-HT₄ a, b, c, or n receptor splice variants (P < 0.05 one-way ANOVA followed by Tukey’s multiple comparisons test).