Embryological studies on the genesis of ano-rectal malformations, using pig models.
Grant-in-Aid for international Scientific Research
|Allocation Type||Single-year Grants|
|Research Institution||Institute of Clinical Medicine|
OHAKWA Haruo Professor, Institute of Clinical Medicine, Tsukuba University, 臨床医学系, 教授 (30009667)
HORI Tetsuo Associate PROF. INST. of Clinical MED., UNIV. of Tsukuba, 臨床医学系, 講師 (80173615)
PUTTE Scfoon ユトレヒト大学, 医学部(オランダ王国), 助教授
MATSUMOTO Masatomo Assistant, INST. of Clinical MED., Tsukuba University, 臨床医学系, 助手 (00229569)
VAN DER PUTTE SCJ Associate Professor, DEPT. of MED., Utrecht University
VANDERPUTTE ユトレヒト大学, 医学部(オランダ王国), 助教授
PUTTE SCT va ユトレヒト大学医学部病理学教室(オランダ), 助教授
|Project Period (FY)
1990 – 1991
Completed(Fiscal Year 1991)
|Budget Amount *help
¥2,100,000 (Direct Cost : ¥2,100,000)
Fiscal Year 1991 : ¥600,000 (Direct Cost : ¥600,000)
Fiscal Year 1990 : ¥1,500,000 (Direct Cost : ¥1,500,000)
|Keywords||Ano-rectal malformations / Anal atresia / Pig model with anal atresia / Cloaca / Cloacal plate / Internal anal sphincter / Three dimensional reconstruction / 三次元立体構築 / 三次元立体構築法 / Cloacal plate / dorsal cloaca / cloac(総排泄腔) / 直腸尿道瘻|
An ano-rectal malformation is one of the most important diseases in pediatric surgery. Various operative methods and their variations have been devised so far. But the operative results of high type of anomalies have not been necessarily satisfactory at all. We have tried to solve these problems from an embryological point of view.
We have already established 2 families of pig model of ano-rectal malformations and have been capable to get anomalous pigs and foetuses from experimental matings. Pig foetuses of 25-60 days were obtained systematically, but there are still defective gestational ages of foetuses. They were supplemented by the materials of University of Utrecht by this co-opearative study, which had been produced from their already extinguished family.
The results of the present studies are followed.
1) Two pig families with malformations have been maintained by Tsukuba University team.
2) Abnormal foetuses of 22-60 days were successfully obtained. But younger ages than 22 days w
ere not obtained, and they were concluded to be impossible to get in the present method of abortion.
3) Early embryological developments of anorectal malformations have been studied with these serially sectioned foetuses. They were studied in combination with those materials in the cooperative research with Utrecht University.
4) Especially for the three dimensional reconstruction studies, over 1, 000 serial sections were necessary from each foetus.
5) The progressive process of the partition between the ano-rectum and urogenital sinus from original cloacal system were ascertained. It was shown by the three dimensional pictures from our own devices. (Mebio 9(1), 1992)
6) Classical explanation and concept of "cloacal membrane" was denied by our research. The defect of cloacal plate between the dorsal cloaca and tail groove were suggested to be a cause of anal atresia. This unsuccessful partition around 30 days in the case of pig is a cause of the anomaly.
7) The inductive role of the cloacal plate was confirmed. But the true story must be confirmed by the materials before 21 days in the future.
8) The development of internal sphincter was confirmed in normal abnormal pigs.
9) The sex difference in the development of anal atresia were clearly explained by this research embryologically. Less
Research Products (26results)