MEDICO-BIOLOGIC RESEARCH 



in stereo-microvasographical studies. These 

 authors also injected OM into both the 

 anterior chamber and Schlemm's canal and 

 found free communication between these 

 structures. 



Tumor vessels were under study by 

 Bohatirchuk (19-13) (24) and Delarue et al. 

 (1956) (-44). Bohatirchuk investigated ex- 

 perimental tumors, mostly their metastases 

 in Brown-Pearce rabbit cancero-sarcoma. 

 Vital injection of thorotrast was used, in 

 some cases complemented by post mortem 

 filling. This author found that scarcity and 

 irregularity characterize neoplastic blood 

 vessels. Many sinuses, cavities and irregu- 

 lar canals are present in the tumor stroma 

 through which evidently blood circulation 

 proceeds. This work is in apparent contra- 

 diction to the work of Delarue et al. (44), 

 who investigated the blood supply in tu- 

 mors of the human large intestine. They 

 found that the blood supply is abundant in 

 tumors. However, the irregularity and scar- 

 city of tumor vessels have only an indirect 

 relation to the tumor blood supply. In one 

 sinus or cavity there may be more blood 

 than in many regular capillaries. In addition 

 to that, the vital injection produces results 

 more reliable than post mortem filling. The 

 profuse hemorrhages w'hich happen fre- 

 quently in tiunors of the large intestine are 

 better explained by the presence of sinuses 

 and cavities within the tumor stroma than 

 by the presence of a plexus of regular blood 

 vessels. Fig. 16 presents kidney metastases 

 of Brown-Pearce tmnor in which large cavi- 

 ties in tumor tissue are conspicuous. Of 

 course, only two works on this subject are 

 insufficient to give a complete answer to 

 this interesting question. 



A very promising and original method of 

 studying blood vessels in situ was used by 

 Bellman and Engfeldt (13) in their experi- 

 ments on the action of gonadotropin on the 

 ovarian blood vessels in the rabbit. The 

 authors put a film wrapped in aluminum 

 foil under the ovaries of the Uving animal, 



Fig. 16. MRD of rabbit kidney with metastases 

 of Brown-Pearce tumor (two of these are seen on 

 the kidnej' surface, approx. in center of the pic- 

 ture), direct vital thorotrast injection, 15 n, ap- 

 prox. X80. 



Large irregular cavities and vessels are seen 

 within both metastases filled with thorotrast. Note 

 the great amount of thorotrast in cavities which 

 indicates that despite the poor development of 

 regular vessels the blood supply of tumor stroma 

 is ampler than in normal organ tissue. 



after which OM was administered and one 

 macroradiograph made, followed with gon- 

 adotropin injection and another macroradio- 

 graph taken on a new film. The considerable 

 enlargement of vessels was found after gona- 

 dotropin. Microradiography confirmed their 

 finding. 



Bellman and Engfeldt (123) studied kid- 

 ney lesions during hypervitaminosis D. 

 Though changes in blood vessels are con- 

 spicuous in the microradiographs presented, 

 the material is not enough to make any final 

 conclusions. 



Our review of works in microvasography is 

 incomplete, yet it is adequate to show that 

 with this method many problems of vascular 

 morphology and of blood circulation may be 



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