Morphometric analyses of the microvasculature of tumors during growth and after x-irradiation
Morphometric methods were used to investigate changes in the microvasculature of C3H/Bi mammary carcinomas during tumor growth and following single-dose x-irradiation of 8 mm average diameter tumors. Estimates included per cent vascular volume, average vessel diameter, and mean vessel length and surface area per unit volume of viable tumor tissue. Necrotic tissue volume was quantitated also. Changes in vascular parameter estimates, particularly a decrease in vascular surface area, indicated that the microvasculature may become less capable of handling the exchange of essential nutrients at an early stage in tumor growth. Following irradiation, there was a transient improvement in colloidal-carbon-filling of tumor microvasculature, and a change in morphological character of vessels toward that seen in smaller tumors, which may improve capability for exchange of essential nutrients. The results support the conclusion that these quantitative methods are of value in studying time and dose relationships in radiotherapy or chemotherapy, particularly in conjunction with other radiobiological methods. (auth) The interaction between the genetically deficient hematopoietic stem cells of W/W/sup v/ mice and the stimulation produced by bacterial endotoxin in irradiated and nonirradiated mice was studied. Effects of 25 mu g S. typhosa endotoxin injected l day before irradiation proved to be similar to effects in +/+ normal mice in several respects. After 300 rads survival was increased from 23% to 77%, recovery of hemoglobin concentration began on day 13 rather than day 17 and granulocyte concentrations were maintained at approximately l500 per mm/sup 3/ compared to a drop to 350 per mm/sup 3/ on day 17 in those given no endotoxin. Erythrocytic spleen colonies were negligible whether or not endotoxin was given. Endotoxin induced granulocytic colonies in significant numbers as early as 5 days after 300 rads, but their peak number (on day 7) was comparable to that seen 4 days after 700 rads in endotoxin treated +/+ mice. Spleen and femur cells of nonirradiated W/W/sup v/ mice given nine daily endotoxin injections produced very few erythrocytic colonies on transplantation into normal irradiated recipients, but a fairly substantial number of granulocytic colonies. This number was, nevertheless, far below that for spleen or femur cells of +/+ mice. When W/W/sup v/ mice were used as recipients instead of irradiated +/+ mice cells from both normal and W/W/sup v/ failed to produce granulocytic colonies. Endotoxin acts as a stem cell and granulopoietic stimulus In W/W/sup v/ mice as it does in +/+ mice, the cellular response to this stimulus being sluggish and subnormal as it is with other stimuli in W/W/sup v/ mice. (auth)
- Research Organization:
- Army Medical Research Inst. of Infectious Diseases, Frederick, MD
- Sponsoring Organization:
- USDOE
- NSA Number:
- NSA-29-016036
- OSTI ID:
- 4356032
- Journal Information:
- Cancer (Philadelphia), Vol. 33, Issue 1; Other Information: Orig. Receipt Date: 30-JUN-74; ISSN 0008-543X
- Country of Publication:
- Country unknown/Code not available
- Language:
- English
Similar Records
Radioprotection of mice with interleukin-1: Relationship to the number of spleen colony-forming units
Dose rate effects on the survival of normal hematopoietic stem cells cells of BALB/c mice