VARIATIONS OF HISTAMINE IN TISSUES AFTER IRRADIATION WITH HIGH DOSES OF GAMMA RAYS

Journal Article · Sun Apr 01 04:00:00 EST 1962 · Atti Accad. Med. Lombarda

OSTI ID:4634682

Mariani, L; Fornasari, F; Giorgi, M

Guinea pigs were exposed to 850, 3250, and 8500 r doses of gamma rays in a Co/sup 60/unit of 8000-C strength for period of 7, 35, and 70 sec, respectively. All animals exposed to 850 r died within 15 days, whereas after the two higher doses, death occurred in 2 to 4 days. Histamine content of blood and various organs was assayed 10 min postexposure. Even at the highest radiation doses, none of the animals showed bronchospasm or other evidence of acute histamine release, such as is seen in anaphylactic shock. Blood histamine content was not affected by 850 r but was reduced about 30% 10 min after 3250 r and 80% after 8500 r. In contrast, anaphylactic shock, induced by intravenous injection of ovalbumin in sensitized guinea pigs, caused a 4-fold rise in blood histamine level. After exposure to 3250 r, the histamine content of the following organs decreased: lung (46%), liver (38%), spleen (37%), kidney (17%), intestine (19%), and uterus (7%). The content did not change in heart. In all of these organs the histamine content fell 40 to 70% following anaphylaxis. Thus massive irradiation lowered tissue histamine to a lesser degree than anaphylaxis and caused a drop rather than a rise in its blood level, as compared with anaphylaxis. However, it was shown that in spite of tissue histamine depletlon in these lethally irradiated animals, they underwent anaphylactic shock (when previously sensitized and then challenged with ovalbumin) of the same severity as unirradiated sensitized guinea pigs. The mechanism by which massive irradiation lowers the histamine content of tissues is unknown, but the possibility that it may damage the enzyme system (histidine decarboxylase) responsible for the generation of histamine is mentioned. (BBB)

• Research Organization: Universita, Milan
• NSA Number: NSA-17-038776
• OSTI ID: 4634682
• Journal Information: Atti Accad. Med. Lombarda, Journal Name: Atti Accad. Med. Lombarda Vol. Vol: 17
• Country of Publication: Country unknown/Code not available
• Language: Italian

Related Subjects

ALBUMINS
AMINES
BIOCHEMISTRY
BIOLOGY AND MEDICINE
BLOOD
COBALT 60
ENZYMES
GAMMA RADIATION
GUINEA PIGS
HEART
HISTAMINE
IMMUNITY
INTESTINE
KIDNEYS
LIVER
LUNGS
QUANTITY RATIO
RADIATION DOSES
RADIATION EFFECTS
SEX
SPLEEN
SURVIVAL TIME
TISSUES
UTERUS