(A) β1/2-AR deletion did not significantly increase phenol red excretion in feces (unpaired t-test, n = 10 in each group); acupuncture at ST37 increased fecal phenol red excretion significantly, relative to non-acupuncture, in both β1/2-AR KO mice and their WT littermates (* P < 0.05, ** P < 0.01; unpaired t-test, n = 10 in each group). (B) β1/2-AR deletion did not increase phenol red excretion in feces significantly (unpaired t-test, n = 10 in each group); Acupuncture at ST25 increased fecal phenol red excretion significantly relative to non-acupuncture in β1/2-AR KO mice (** P < 0.01; unpaired t-test, n = 10 in each group); (C) M2/3-R deletion increased phenol red excretion in feces significantly (## P < 0.01, unpaired t-test, n = 10 in each group); Acupuncture at ST37 facilitated fecal phenol red excretion significantly relative to non-acupuncture in WT littermates (** P < 0.01; unpaired t-test, n = 10 in each group). (D) M2/3-R deletion increased phenol red excretion in feces significantly (## P < 0.01, unpaired t-test, n = 10 in each group); Acupuncture at ST25 decreased fecal phenol red excretion significantly relative to non-acupuncture in M2/3-R KO mice (*P < 0.05; unpaired t-test, n = 10 in each group). (E) The rate of increase in phenol red excretion induced by acupuncture at ST37 in β1/2-AR KO mice was not significantly different from that in WT littermates (unpaired t-test, n = 10 in each group). Deletion of M2/3-Rs significantly abolished the increase in phenol red excretion induced by acupuncture at ST37 compared with that in WT littermates (** P < 0.01, unpaired t-test, n = 10 in each group). (F) β1/2-AR knockout significantly diminished the decrease in phenol red excretion induced by acupuncture at ST25 relative to WT littermates (** P < 0.01, unpaired t-test, n = 10 in each group); the change in phenol red excretion induced by acupuncture at ST25 in M2/3-R KO mice was significantly different from that in WT littermates (** P < 0.01, unpaired t-test, n = 10 in each group).