Detailed characteristics of the migrating motor complex in Man and Animals

Interdigestive dönemde tek mideli türlerde mid eve ince barsaklar tamamen boştur. Başlangıç periyodunda tüketilen gıdalar sindirim ve transport işlemine uğrarlar. Bununla birlikte nispeten küçük miktarlarda sindirilemeyen gıda kalıntıları, hücresel döküntüler, bakteri ve muhtemelen çok az miktarda sindirilemeyen sıvı ve katı gıdalar gastrointestinal lümende kalır. Sindirim sıvılarının salgılanması açlık safhasında tamamen inhibe edilmez ve gastrointestinal lümende sindirim sıvılarının kalması bu safhada lüminal içeriğin taşınmasının ana sebeplerindendir. Yemek sonrasında olduğu gibi gastrointestinal gıda karışımının aralıksız olmasına da gerek yoktur. Dolayısıyla gıda almayan insane ve tek mideli hayvanlarda mevcut motor aktivitenin özelliği gerçek durumlara uyum sağlar ve interdigestive motilite siklik özelliktedir. Bu nedenle siklik motor aktivite olarak tanımlanır ve bu sikluslar göç eden motor kompleksler (MMCs) olarak kabul edilirler. MMC gittikçe artan kontraksiyon yağunluğu gösteren dört safhayı kapsamaktadır; genelde en uzun safha olan bazende faz IIa ve IIb olarakta ayrılan faz II döneminde, kontraksiyon şiddeti ve sıklığı belirlenmektedir; faz III sırasında en güçlü kontraksiyonlar maksimum sıklıkta belirlenir; her zaman belirlenemeyen faz IV döneminde faz II dönemine benzer düzensiz azami olmayan kasılmalar kaydedilir. MMC tanımlanmasında kesin kriterler mevcuttur ve bu normal ve anormal MMCs durumların ayırt edilmesini mümkün kılar. Birçok memeli ve kuşlarda gerçekleşen bu açlık dönemleri fötal yaşamda organize edilmekte ve ruminat ve diğer ot oburlar gibi bazı türlerde beslemeyle ortadan kalkmamaktadır. Monometrik teknikler hala insan ve hayvanlarda en azından gastric ve intestinal MMC kaydedilmesinde altın standart metot olarak görünerek interdigestive motilitenin detaylı analizini klinik amaçla kullanılan diğer minimal invaziv metotlardan daha detaylı nalizlerine imkan vermektedir.

İnsanda ve hayvanlarda göç edici motor kompleksin özellikleri

During the interdigestive state occurring in monogastric species, the stomach and small intestine are almost empty. The meal consumed during the foregoing period undergoes the digestive and transport processes. Notwithstanding, the relatively small amounts of indigestible food remnants, cellular debris, bacteria and possibly the small portions of ingested liquids and solid foods may remain in the gastrointestinal lumen. The secretion of the digestive juices is not inhibited completely during the fasting state and the presence of the digestive juices in the gastrointestinal lumen appears to be one of the main reasons to maintain the transport of the luminal content during this period. There is no need to retain an uninterrupted mixing of gastrointestinal flow of digesta as it occurs during the postprandial period. Thus, the character of motor activity present in nonfed humans and monogastric animals adapts to the actual conditions and the interdigestive motility exhibits the cyclical character. Therefore, it was defined as cyclic motor activity and these cycles are regarded as the migrating motor complexes (MMCs). The MMC comprises four phases exhibiting the exponential intensity of contractions: phase I was defined as the weakest or with no contractions; during usually the longest phase II, divided sometimes into phase IIa and IIb, the increased frequency and amplitude of contractions are noticed; in the course of phase III, the strongest contractions occur at the maximal frequency; during phase IV, not always observed, the irregular submaximal contractions, similar to those during phase II can be recorded. There are quite precise criteria for MMC identification and it is possible to distinguish normal and abnormal MMCs. This fasting pattern occurring in most mammals and birds, is organized during the fetal life and in some species, like ruminants and other herbivores, is not abolished by feeding. The manometric technique still appears to be the gold standard method in man and promising in animals at least for the gastric and small-intestinal MMC registration to allow more detailed analysis of the interdigestive motility than the other minimally invasive methods used for clinical purposes.

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Kafkas Üniversitesi Veteriner Fakültesi Dergisi-Cover
  • ISSN: 1300-6045
  • Yayın Aralığı: Yılda 6 Sayı
  • Başlangıç: 1995
  • Yayıncı: Kafkas Üniv. Veteriner Fak.