Effects of boron neutron capture irradiation on the normal lung of rats.
The whole lung of rats was irradiated with X-rays, thermal neutrons, or thermal neutrons in the presence of p-boronophenylalanine (BPA). A >/= 20% increase in breathing rate, in the period 40-80 days after irradiation, was indicative of radiation-induced pneumonitis. The ED(50) (+/-SE) for a >/= 20% increase in breathing rate, relative to age-matched controls, was 11.6 +/- 0.13 Gy for X-rays and 9.6 +/- 0.08 Gy for neutrons only. This indicated a thermal neutron beam RBE of 1.2 and an RBE of 2.2 for the high-LET components of the dose, assuming a dose reduction factor of 1.0 for gamma rays. Preliminary data indicate the compound biological effectiveness factor for BPA in the lung is approximately 1.5.
Nuclear Engineering Department, Massachusetts Institute of Technology, 150 Albany Street, Cambridge, MA 02139, USA.
J L
JL
Kiger
W S
WS
Kiger
H
H
Patel
P J
PJ
Binns
K J
KJ
Riley
J W
JW
Hopewell
O K
OK
Harling
J A
JA
Coderre
D000818:Animals; D001896:Boron Compounds; D016754:Boron Neutron Capture Therapy / Q000009:adverse effects* / Q000295:instrumentation / Q000706:statistics & numerical data; D004307:Dose-Response Relationship, Radiation; D008168:Lung / Q000503:physiopathology / Q000528:radiation effects*; D008297:Male; D019047:Phantoms, Imaging; D010649:Phenylalanine / Q000031:analogs & derivatives*; D017564:Radiation Pneumonitis / Q000209:etiology* / Q000503:physiopathology; D011874:Radiometry / Q000706:statistics & numerical data; D051381:Rats; D011916:Rats, Inbred F344; D012062:Relative Biological Effectiveness; D012119:Respiration / Q000528:radiation effects
C436045:4-dihydroxyborylphenylalanine; D001896:Boron Compounds; D010649:Phenylalanine