Photodynamic ablation of early pregnancy in the rat with 5-aminolevulinic acid: a potential new therapy for tubal ectopic pregnancy in the human.
OBJECTIVE
To determine whether systemic 5-aminolevulinic acid (ALA) could produce photosensitization and photodynamic ablation of early pregnancy in the rat.


METHODS
A conventional laboratory setting.


METHODS
Female Sprague-Dawley rats, weighing 220 to 275 g at the time of breeding.


METHODS
Rats at 10 days of gestation were injected IV with saline, 20 or 200 mg/kg ALA. Three hours later, the abdominal cavity was opened to record the number of fetuses in both uterine horns. One or both uterine horns were exposed to photoactivating light at 630 nm for 0, 5, 15, or 30 minutes.


METHODS
Mean fetal survival rate was determined 7 days after treatment.


RESULTS
The mean +/- SEM fetal survival rates in groups (n = 6) treated with saline, 20 or 200 mg/kg ALA followed by 30-minute light exposure were 90.8% +/- 2.8%, 16.0% +/- 4.9%, and 0%, respectively. The mean +/- SEM fetal survival rates in groups (n = 6) treated with 200 mg/kg ALA followed by 0-, 5-, 15-, or 30-minute light exposure were 71.3% +/- 11.8%, 8.9% +/- 6.2%, 0.9% +/- 1.3%, and 0%, respectively.


CONCLUSIONS
We conclude that systemic ALA followed by transmural exposure to photoactivating light (630 nm) results in resorption of early pregnancies in the rat. This approach could potentially be developed as a new treatment for human ectopic pregnancy.
Yang
J Z
JZ
Department of Physiology, Queens's University, Kingston, Ontario, Canada.
Van Vugt
D A
DA
Melchior
M F
MF
Hahn
P M
PM
Reid
R L
RL
D000622:Aminolevulinic Acid / Q000008:administration & dosage / Q000494:pharmacology*; D000818:Animals; D004305:Dose-Response Relationship, Drug; D005260:Female; D005327:Fetal Resorption; D008027:Light; D010778:Photochemotherapy; D011247:Pregnancy; D011270:Pregnancy, Animal / Q000187:drug effects*; D011271:Pregnancy, Ectopic / Q000188:drug therapy; D051381:Rats; D017207:Rats, Sprague-Dawley
D000622:Aminolevulinic Acid