Distribution of microspheres in plantaris muscles of resting and exercising rats as a function of fiber type.
Distribution of microspheres in plantaris muscles of resting and exercising rats as a function of fiber type.
复制标题
微球在休息和运动大鼠跖肌中的分布作为纤维类型的函数。
DOI：
10.1002/aja.1001820403
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发表时间：
1988
期刊：
影响因子：
--
通讯作者：
Armstrong,RB
中科院分区：
文献类型：
--
作者：
Ong,TC;Hayes,DA;Armstrong,RB
本研究的目的是在组织学上确定微球（MS）（14 μm）的分布，从而确定大鼠跖肌中相对于纤维类型（快缩-氧化-糖酵解[FOG]、快缩-糖酵解[FG]和慢缩-氧化[SO]）的血流量相对分布。研究了三种情况：（1）运动前站立;（2）以15 m/min的速度进行跑步机运动（快速行走）;（3）以60 m/min的速度进行跑步机运动（中度疾驰）。将MS悬液（含1 × 106 MS）在3种条件下通过颈动脉导管注入升主动脉，使MS按其各自的血流量比例分布于组织中。切下跖肌切片（20 μ m），测定还原型烟酰胺腺嘌呤二核苷酸四唑还原酶（NADH-TR）和肌原纤维腺苷三磷酸酶（ATP酶）活性，以便将纤维分型为SO、FOG或FG。MS位于NADH-TR切片中，并对MS旁边的纤维进行分类和计数。将在每种条件下观察到的与MS相邻的每种类型的纤维数量与基于MS随机分布在组织中的假设的相邻纤维的预测数量进行比较。该分析表明，MS（和血流）优先分配到SO纤维在运动前，SO和FOG纤维在缓慢运动，和FOG纤维在快速运动。这些数据支持这样的论点，即血流量分布在有意识的动物的肌肉纤维类型和运动强度的功能。
The purpose of this study was to determine histologically the distribution of microspheres (MSs) (14 μm), and hence the relative distribution of blood flow, in rat plantaris muscle relative to the fiber types (fast‐twitch‐oxidative‐glycolytic [FOG], fast‐twitch‐glycolytic [FG], and slow‐twitch‐oxidative [SO]). Three conditions were investigated: (1) preexercise standing; (2) treadmill locomotion at 15 m/min (fast walking); and (3) treadmill locomotion at 60 m/min (moderate galloping). The MS suspension (containing 1 × 106MSs) was infused into the ascending aorta via a catheter in the carotid artery under each of the 3 conditions so that MSs were distributed to the tissues in proportion to their respective blood flows. Sections (20 m̈m) of the plantaris muscle were cut and assayed for reduced nicotinamide adenine dinucleotide tetrazolium reductase (NADH‐TR) and myofibrillar adenosine triphosphatase (ATPase) activities so the fibers could be typed as SO, FOG, or FG. MSs were located in the NADH‐TR sections, and the fibers next to the MSs were classified and counted. The observed numbers of fibers of each type in each condition that were adjacent to MSs were compared to the predicted number of adjacent fibers based on the assumption the MSs were randomly distributed in the tissue. This analysis demonstrated that MSs (and blood flows) were preferentially distributed to SO fibers during preexercise, to SO and FOG fibers during slow locomotion, and to FOG fibers during fast locomotion. The data support the contention that blood flow is distributed in muscles of conscious animals as functions of fiber type and exercise intensity.