Studies <jn tlie Kiulocriiie (Hands 205 



The base of the riglit lung seems slightly congested. Tiie intestine and 

 its contents and the organs of tiie body generally appear normal. 



Pancreas. — The nuclei of the alveolar cells var}- in size from 37/x 

 to bfx, but some are as large as 7'5/x, and there are even a few as 

 large as lO/x. They lie near the base of the cells. Some of them 

 contain large nucleoli, with a tendency for the chromatin granules 

 to be arranged near the periphery of the nucleus, whilst otiiers have 

 uniformly scattered coarse chrouiatin granules. All the nucleoli are 

 stained blue by Mallory. Mixed with the ordinary larger rounded- 

 angular cells are many smaller cells. The zymogen granules are 

 much fewer than either in the control or in the parathyroid- 

 ectomised animal. The cells of the islets and the centro-aciuar cells 

 exhibit no diti'erences from the normal. 



Summary of the Effects of Parathyroidectomy and 

 Thyroidectomy upon the Pancreas, 



1. Parathyroidectomy produces comparatively little change in the 

 structural appearances of the pancreas. But the alveolar cells are some- 

 what smaller, and their cytoplasm less compact in structure, exhibiting 

 numerous small vacuoles and crevices (appearance of canalisation). There 

 is rather less zymogen than in the normal pancreas. 



2. Thyroidectomy is followed by the appearance of many small cells 

 in the alveoli, and Ijy an enlargement of many of the cell-nuclei. There is 

 a greater diminution of zymogen than after parathyroidectomy. 



3. The islets of Langerhans appear unaltered as the result of these 

 operations. 



4. No mitoses are visible after either operation. 



Effects of Thyroid Feeding on Pancreas. 



The remaining rats of each of the three groups A, B, and C were, from 

 now on, fed with the paste of ground rusks and water (without meat), to 

 which was added 1 grm. of dry ox-thyroid per rat per diem : this diet was 

 maintained for one week, from March 25 to 31. From the third day of the 

 addition of thyroid to the diet the animals of all the groups were observed 

 to be less active than before and to be losing weight. The appetite decreased 

 to a remarkable extent. Some of the animals showed marked emaciation ; 

 several suffered from diarrhcea; and the hair was shed to a much greater 

 extent than usual. At the end of the week one rat (No. 2) of each group 

 was killed. The following are the findings : — 



(a) In Unoperated Animal. 



No. 2 rat of A group. Thyroid-fed. Weight 140 grm. 

 Both the small and large intestines are somewhat congested. The 

 contents of the laro^e intestine are soft. 



