Effect of 4-hydroxypyrazolo (3,4-d) pyrimidine (allopurinol) on postirradiation cerebral blood flow: implications of free radical involvement

Journal Article · Fri Jan 01 04:00:00 EST 1988 · Free Radical Biol. Med.; (United States)

DOI:https://doi.org/10.1016/0891-5849(88)90048-2· OSTI ID:6968741

Cockerham, L G; Arroyo, C M; Hampton, J D

In an attempt to elucidate mechanisms underlying the irradiation-induced decrease in regional cerebral blood flow (rCBF) in primates, hippocampal and hypothalamic blood flows of rhesus monkeys were measured by hydrogen clearance, before and after exposure to 100 Gy, whole body, gamma irradiation. Systemic blood pressures were monitored simultaneously. Compared to control animals, the irradiated monkeys exhibited an abrupt decline in systemic blood pressure to 35% of the preirradiation level within 10 min postirradiation, falling to 12% by 60 min. A decrease in hippocampal blood flow to 32% of the preirradiation level was noted at 10 min postirradiation, followed by a slight recovery to 43% at 30 min and a decline to 23% by 60 min. The hypothalamic blood flow of the same animals showed a steady decrease to 43% of the preirradiation levels by 60 min postirradiation. The postradiation systemic blood pressure of the allopurinol treated monkeys was not statistically different from the untreated, irradiated monkeys and was statistically different from the control monkeys. However, the treated, irradiated monkeys displayed rCBF values that were not significantly different from the nonirradiated controls. These findings suggest the involvement of free radicals in the postirradiation decrease in regional cerebral blood flow but not necessarily in the postirradiation hypotension seen in the primate.

• Research Organization: Armed Forces Radiobiology Research Institute, Bethesda, MD (USA)
• OSTI ID: 6968741
• Journal Information: Free Radical Biol. Med.; (United States), Journal Name: Free Radical Biol. Med.; (United States) Vol. 4:5; ISSN FRBME
• Country of Publication: United States
• Language: English

Related Subjects

560152* -- Radiation Effects on Animals-- Animals
63 RADIATION, THERMAL, AND OTHER ENVIRON. POLLUTANT EFFECTS ON LIVING ORGS. AND BIOL. MAT.
ANIMALS
AZINES
BIOCHEMICAL REACTION KINETICS
BIOLOGICAL EFFECTS
BIOLOGICAL RADIATION EFFECTS
BLOOD FLOW
BLOOD PRESSURE
BODY
BRAIN
CENTRAL NERVOUS SYSTEM
CEREBRUM
ELECTROMAGNETIC RADIATION
EXTERNAL IRRADIATION
GAMMA RADIATION
HETEROCYCLIC COMPOUNDS
HIPPOCAMPUS
HYPOTHALAMUS
IONIZING RADIATIONS
IRRADIATION
KINETICS
MAMMALS
MONKEYS
NERVOUS SYSTEM
ORGANIC COMPOUNDS
ORGANIC NITROGEN COMPOUNDS
ORGANS
PRIMATES
PYRIMIDINES
RADIATION EFFECTS
RADIATIONS
RADICALS
RADIOSENSITIVITY EFFECTS
REACTION KINETICS
VERTEBRATES
WHOLE-BODY IRRADIATION