Radiological Study of Motility of Gastro-Intestinal Tract of Rachitic Rats.

Although rickets is a disease primarily affecting the skeletal parts it nevertheless produces abnormal changes in the entire body. It is usually associated with muscular weakness and relaxation and since one of the early symptoms of rickets is constipation, the following experiments were planned to compare radiologically the motility of the gastrointestinal tract of rachitic rats with that of normals.

In these experiments 40 rats were used, 20 rachitic and 20 normal. Many of this number had to be discarded during the work for various reasons. The animals were from a uniform strain of Albino rats raised by one of us (S.N.B.) from Wistar Institute Stock. The litters were equally divided among the normal and rachitic groups. The normal groups received adequate diet. The rachitic groups were fed a rachitogenic diet, (McCollum 3143) until definite rachitic bone changes were visible by means of the x-rays. These animals were kept in individual cages in the x-ray laboratory for 3 days prior to receiving the bariumized meal, in order to let them become accustomed to the noises of the x-ray apparatus so that their motility would not be disturbed. It was shown that psychic influences such as fear and anger markedly retarded the motility of the gastro-intestinal tract. This was clearly demonstrated by the prolonged emptying time of the rats which were tied to wooden racks so as to make roentgenograms. After the rats were fasted for 48 hours and water withheld 24 hours they were given a barium meal composed of 10 gm. of barium sulphate and 10 cc. of buttermilk and were allowed to eat for 20 minutes, when they were fluoroscoped immediately in loose cotton sacks to ascertain whether their stomachs were full.