Dept. of Physiology and Cell Biology, Univ. of Nevada School of Medicine, Reno, 89557, USA.
Am J Physiol Gastrointest Liver Physiol. 2010 May;298(5):G643-56. doi: 10.1152/ajpgi.00260.2009. Epub 2010 Feb 11.
The morphology of interstitial cells of Cajal (ICC) in the circular muscle layer of the cynomolgus monkey internal anal sphincter (IAS) and rectum and their relationship to sympathetic and nitrergic nerves were compared by dual-labeling immunohistochemistry. Contractile studies confirmed that nitrergic nerves participate in neural inhibition in both regions whereas sympathetic nerves serve as excitatory motor nerves only in the IAS. Muscle bundles extended from myenteric to submucosal edge in rectum but in the IAS bundles were further divided into "minibundles" each surrounded by connective tissue. Dual labeling of KIT and smooth muscle myosin revealed KIT-positive stellate-shaped ICC (ICC-IAS) within each minibundle. In the rectum intramuscular ICC (ICC-IM) were spindle shaped whereas stellate-shaped ICC were located at the myenteric surface (ICC-MY). ICC were absent from both the myenteric and submucosal surfaces of the IAS. Nitrergic nerves (identified with anti-neuronal nitric oxide synthase antibodies or NADPH diaphorase activity) and sympathetic nerves (identified with anti-tyrosine hydroxylase antibody) each formed a plexus at the myenteric surface of the rectum but not the IAS. Intramuscular neuronal nitric oxide synthase- and tyrosine hydroxylase-positive fibers were present in both regions but were only closely associated with ICC-IM in rectum. Minimal association was also noted between ICC-IAS and cells expressing the nonspecific neuronal marker PGP9.5. In conclusion, the morphology of rectal ICC-IM and ICC-MY is similar to that described elsewhere in the gastrointestinal tract whereas ICC-IAS are unique. The distribution of stellate-shaped ICC-IAS throughout the musculature and their absence from both the myenteric and submucosal surfaces suggest that ICC-IAS may serve as pacemaker cells in this muscle whereas their limited relationship to nerves suggests that they are not involved in neuromuscular transmission. Additionally, the presence of numerous minibundles, each containing both ICC-IAS and nerves, suggests that this muscle functions as a multiunit type muscle.
采用双重免疫组织化学染色的方法比较了食蟹猴肛门内括约肌（IAS）和直肠环状肌层中 Cajal 间质细胞（ICC）的形态及其与交感神经和氮能神经的关系。收缩研究证实，氮能神经参与两个区域的神经抑制，而交感神经仅作为 IAS 的兴奋性运动神经。直肠的肌束从肌间延伸到黏膜下层边缘，但在 IAS 中，束进一步分为“小束”，每个小束都被结缔组织包围。KIT 和平滑肌肌球蛋白的双重标记显示，每个小束内都有 KIT 阳性的星状 ICC（ICC-IAS）。在直肠中，ICC-IM 呈梭形，而星状 ICC 位于肌间表面（ICC-MY）。IAS 的肌间和黏膜下表面均没有 ICC。氮能神经（用神经元型一氧化氮合酶抗体或 NADPH 黄递酶活性鉴定）和交感神经（用酪氨酸羟化酶抗体鉴定）在直肠的肌间表面形成一个神经丛，但在 IAS 中没有。两种神经都存在于肌间神经元型一氧化氮合酶和酪氨酸羟化酶阳性纤维中，但仅在直肠中与 ICC-IM 密切相关。ICC-IAS 与表达非特异性神经元标志物 PGP9.5 的细胞之间也存在最小的关联。总之，直肠 ICC-IM 和 ICC-MY 的形态与胃肠道其他部位描述的形态相似，而 ICC-IAS 是独特的。星状 ICC-IAS 分布在整个肌肉中，并且它们不存在于肌间和黏膜下层表面，这表明 ICC-IAS 可能作为该肌肉的起搏细胞，而它们与神经的有限关系表明它们不参与神经肌肉传递。此外，存在许多小束，每个小束都包含 ICC-IAS 和神经，这表明这种肌肉作为一种多单位类型的肌肉起作用。
