AIM:To observe the effects of mouse nerve growth factor(NGF),rat recombinant brain derived neurotrophic factor(rm-BDNF)and recombinant human neurotrophin-3(rh-NT-3)on the gastrointestinal motility and the migratingmyoelectric complex(MMC)in rat.METHODS:A randomized,double-blinded,placebo-controlledexperiment was performed.5-7 days after we chronicallyimplanted four or five bipolar silver electrodes on thestomach,duodenum,jejunum and colon,21 experimentalrats were coded and divided into 3 groups and injectedNGF,rm-BDNF,rh-NT-3 or placebo respectively via tail veinat a dose of 20 μg·kg~(-1).The gastrointestinal myoelectricalactivity was recorded 2 hours before and after the testsubstance infusions in these consciously fasting rats.RESULTS:The neurotrophins-induced pattern of activitywas characterized by enhanced spiking activity of differentamplitudes at all recording sites,especially in the colon.Inthe gastric antrum and intestine,only rh-NT-3 had increasedeffects on the demographic characteristics of electricalactivities(P<0.05),but did not affect the intervals of MMCs.In the colon,all the three kinds of neurotrophins couldsignificantly increase the frequency,amplitude and durationlevels of spike bursts,and also rh-NT-3 could prolong theintervals of MMC in the transverse colon(25±11 min vs19±6 min,P<0.05).In the distal colon rh-NT-3 could evokephase Ⅲ-like activity and disrupt the MMC pattern,whichwas replaced by a continuously long spike bursts(LSB)andirregular spike activity(ISA)for 48±6 min.CONCLUSION: Exogenous neurotrophic factors can stimulate gut myoelectric activities in rats. AIM: To observe the effects of mouse nerve growth factor (NGF), rat recombinant brain derived neurotrophic factor (rm-BDNF) and recombinant human neurotrophin-3 (rh- NT-3) on the gastrointestinal motility and the migrating myoelectric complex in rat. METHODS: A randomized, double-blinded, placebo-controlledexperiment was performed.5-7 days after we chronically implanted four or five bipolar silver electrodes on the stomach, duodenum, jejunum and colon, 21 experimental rats were coded and divided into 3 groups and injectedNGF, rm-BDNF, rh-NT-3 or placebo respectively via vein vein a a dose of 20 μg · kg -1. The gastrointestinal myoelectric activity was recorded 2 hours before and after the testsubstance infusions in these consciously fasting rats .RESULTS : The neurotrophins-induced pattern of activity was characterized by enhanced spiking activity of different amplitudes at all recording sites, especially in the colon. Inthe gastric antrum and intestine, only rh-NT-3 had increased effects on the demographic c haracteristics of electricalactivities (P <0.05), but did not affect the intervals of MMCs. The colon, all the three kinds of neurotrophins couldsignificantly increase the frequency, amplitude and durationlevels of spike bursts, and also rh-NT-3 could prolong theintervals of MMC in the transverse colon (25 ± 11 min vs19 ± 6 min, P <0.05) .In the distal colon rh-NT-3 could evokephase Ⅲ-like activity and disrupt the MMC pattern, whichwas replaced by a continuous long spike bursts (LSB) andirregular spike activity (ISA) for 48 ± 6 min. CONCLUSION: Exogenous neurotrophic factors can stimulate gut myoelectric activities in rats.