Abstract:
Rhythmic electrical events, termed slow waves, govern the timing and amplitude of phasic contractions of the gastric musculature. Extracellular multielectrode measurement of gastric slow waves can be a biomarker for phenotypes of motility dysfunction. However, a gastric slow-wave conduction pathway for the rat, a common animal model, is unestablished. In this study, the validity of extracellular recording was demonstrated in vitro with simultaneous intracellular and extracellular recordings and by pharmacological inhibition of slow waves. The conduction pathway was determined by in vivo extracellular recordings while considering the effect of motion. Slow-wave characteristics [means (SD)] varied regionally having higher amplitude in the antrum than the distal corpus [1.03 (0.12) mV vs. 0.75 (0.31) mV; n = 7; P = 0.025 paired t test] and faster propagation near the greater curvature than the lesser curvature [1.00 (0.14) mm·s-1 vs. 0.74 (0.14) mm·s-1; n = 9 GC, 7 LC; P = 0.003 unpaired t test]. Notably, in some subjects, separate wavefronts propagated near the lesser and greater curvatures with a loosely coupled region occurring in the area near the distal corpus midline at the interface of the two wavefronts. This region had either the greater or lesser curvature wavefront propagating through it in a time-varying manner. The conduction pattern suggests that slow waves in the rat stomach form annular wavefronts in the antrum and not the corpus. This study has implications for interpretation of the relationship between slow waves, the interstitial cells of Cajal network structure, smooth muscles, and gastric motility.NEW & NOTEWORTHY Mapping of rat gastric slow waves showed regional variations in their organization. In some subjects, separate wavefronts propagated near the lesser and greater curvatures with a loosely coupled region near the midline, between the wavefronts, having a varying slow-wave origin. Furthermore, simultaneous intracellular and extracellular recordings were concordant and independent of movement artifacts, indicating that extracellular recordings can be interpreted in terms of their intracellular counterparts when intracellular recording is not possible.
摘要:
有节奏的电事件,称为慢波,控制胃肌肉组织阶段性收缩的时间和幅度。胃慢波的细胞外多电极测量可以是运动功能障碍表型的生物标志物。然而,大鼠的胃慢波传导通路,一个普通的动物模型,是不确定的。在这项研究中,通过同时进行细胞内和细胞外记录以及对慢波的药理学抑制,在体外证明了细胞外记录的有效性。通过体内细胞外记录确定传导途径,同时考虑运动的影响。慢波特性(平均值(SD))区域变化,在胃窦中的振幅高于远端主体(1.03(0.12)mVvs0.75(0.31)mV;n=7;p=0.025配对t检验),并且在较大曲率附近的传播比较小曲率(1.00(0.14)mms-1vs0.74(0.14)mms-1;n=9GC,7LC;p=0.003未配对t检验)。值得注意的是,在某些学科中,在较小和较大曲率附近传播的单独波前,在远端本体中线附近的区域出现松散耦合区域,在两个波前的交界处。该区域具有较大或较小曲率的波前以时变方式传播通过它。传导模式表明,大鼠胃中的慢波在胃窦而不是主体中形成环形波前。这项研究对解释慢波之间的关系,Cajal网络结构的间质细胞,平滑肌,和胃动力。