MITOTIC EFFECTS OF IONIZING RADIATION ON THE VIRULENT AND MILD EPIDERMAL HYPERPLASIA OF MICE. PART III. GENERAL IMPORTANCE OF PATHOLOGICAL MITOSES IN MOUSE EPIDERMIS

Journal Article · Wed May 01 04:00:00 EDT 1963 · Strahlentherapie (West Germany)

OSTI ID:4702714

Setaelae, K; Lindroos, B; Nyyssoenen, O

A comparison was made of the mitotic behavior in three different conditions of the same target tissue, the mouse epidermis: In malignant epidermal hyperplasia (provoked hy the carcinogen 9,10-dimethyl-1,2-benzathracene) characterized by low mitotic activity as well as by delayed and misguided cell maturation, in benign epidermal hyperplasia (provoked by the tumor enhancer Tween 60) characterized by extremely high mitotic rate and by almost normal cell maturation, and in simple regenerative epidermal hyperplasia (caused by wounding of the skin with a razor blade). In parallel experiments, mice of RA strain (mice resistant to skin-tumor evolution) and mice of Swiss CF 1 strain (mice highly susceptible to skin-tumor evolution) were used. In each animal in each series, 500 mitoses (normal or pathologic) were registered. The material comprised a total of 50 000 mitotic figures. The occurrence of pathologic mitoses in the mouse epidermis is not an expression of an already existing malignant process; their appearance is not correlated to the intensity of the cell renewal; instead their occurrence is largely strain-dependent; neither the occurrence of mitotic aberrations nor their morphology can be used as criteria in estimations of possible specific affects of noxious agents, as just the same aberrations appear in the target tissue after exposure to carcinogen, tumor enhancer, radiomimetics, the hypnotic sodium pentobarbital, ionizing radiation, or mechanical wounding of the skin. The results indicate that a number of previously uncontrolled factors must be accounted for in the evaluation of mitotic disturbances. (auth)

• Research Organization: Univ. of Helsinki
• NSA Number: NSA-17-028755
• OSTI ID: 4702714
• Journal Information: Strahlentherapie (West Germany), Journal Name: Strahlentherapie (West Germany) Vol. Vol: 121; ISSN STRAA
• Country of Publication: Country unknown/Code not available
• Language: German

Related Subjects

ANESTHESIA
AROMATICS
BARBITURIC ACID
BENZANTHRACENE
BIOLOGY AND MEDICINE
CANCER
CARCINOGENESIS
CHEMICALS
CYTOLOGY
DRUGS
GAMMA RADIATION
HETEROCYCLICS
MICE
MITOSIS
ORGANIC NITROGEN COMPOUNDS
RADIATION EFFECTS
REGENERATION
SENSITIVITY
SKIN
TISSUES
TOXICITY
TUMORS
X RADIATION