Sequelae of prenatal serotonin depletion and stress on pain sensitivity in rats.
The effects of interrupted synthesis of serotonin (5-HT) and immobilization stress applied to pregnant Wistar rats on behavioral measures of pain sensitivity in the formalin test were studied in their offspring at age 90 days. Prenatal 5-HT depletion decreased pain sensitivity in one third of rats and produced no significant change in the remainder. However, the latter showed a clear tendency to an increase in the interphase interval in females and a decrease in males. Prenatal stress increased pain sensitivity in 50% of rats with prenatal 5-HT deficiency and decreased pain sensitivity in the remainder. Increases in pain sensitivity were also seen in control rats (with prenatal injections of physiological saline), though to a significantly lesser extent than in animals with prenatal 5-HT depletion. The latter showed gender differences in the effects of prenatal stress on pain sensitivity. The present data provide evidence that prenatal 5-HT depletion has long-term effects on the functional activity of the nociceptive system and the important role of 5-HT in mediating the effects of prenatal stress on pain sensitivity in the formalin test.
Butkevich
I P
IP
I. P. Pavlov Institute of Physiology, Russian Academy of Sciences, 6 Makarov Bank, 199034 St. Petersburg, Russia. mik@kolt.infran.ru
Mikhailenko
V A
VA
Leont'eva
M N
MN
D000818:Animals; D001522:Behavior, Animal; D005260:Female; D008297:Male; D010147:Pain Measurement / Q000379:methods; D017288:Pain Threshold / Q000502:physiology*; D011247:Pregnancy; D011297:Prenatal Exposure Delayed Effects; D051381:Rats; D017208:Rats, Wistar; D012149:Restraint, Physical / Q000379:methods; D012701:Serotonin / Q000172:deficiency*; D012737:Sex Factors; D018709:Statistics, Nonparametric; D013315:Stress, Psychological / Q000503:physiopathology*; D013997:Time Factors; D010133:p-Chloroamphetamine / Q000494:pharmacology
D012701:Serotonin; D010133:p-Chloroamphetamine