title: Peri, pre and postnatal morphine exposure: exposure-induced effects and sex differences in the behavioural consequences in rat offspring.
abstract: This study investigated the behavioural consequences of peri, pre and postnatal morphine (MO) exposure in rats. From gestational day 1 dams were treated with either saline or MO subcutaneously once a day (5 mg/kg on the first 2 days, 10 mg/kg subsequently). Spontaneous locomotor activity in a new environment (habituation) and antinociceptive effects of MO were measured separately in male and female pups after weaning and also in late adolescence or adulthood. The rewarding effect of MO was assessed by conditioned place preference in adult animals. Both exposure-induced and sex differences were observed. A significant delay in habituation to a new environment and decreased sensitivity to the antinociceptive effect of MO were found in male offspring of MO-treated dams. In contrast, the place preference induced by MO was enhanced in the MO-exposed adult animals and this effect was more marked in females. Prenatal exposure to MO resulted in more marked changes than the postnatal exposure through maternal milk. The results indicate that a medium MO dose administered once-daily results in long-term consequences in offspring and may make them more vulnerable to MO abuse in adulthood.
authors.affiliation: Department of Pharmacology and Pharmacotherapy, Semmelweis University, Budapest, Hungary. timjul@pharma.sote.hu
authors.forename: Julia
authors.initials: J
authors.lastname: Timár
authors.forename: Melinda
authors.initials: M
authors.lastname: Sobor
authors.forename: Kornél P
authors.initials: KP
authors.lastname: Király
authors.forename: Susanna
authors.initials: S
authors.lastname: Gyarmati
authors.forename: Pál
authors.initials: P
authors.lastname: Riba
authors.forename: Mahmoud
authors.initials: M
authors.lastname: Al-Khrasani
authors.forename: Susanna
authors.initials: S
authors.lastname: Fürst
mesh_terms: D000818:Animals; D000833:Animals, Suckling; D001724:Birth Weight / Q000187:drug effects; D002755:Choice Behavior / Q000187:drug effects; D003216:Conditioning, Operant / Q000187:drug effects; D005260:Female; D006185:Habituation, Psychophysiologic / Q000187:drug effects*; D008297:Male; D009020:Morphine / Q000009:adverse effects* / Q000494:pharmacology; D009294:Narcotics / Q000009:adverse effects* / Q000494:pharmacology; D017288:Pain Threshold / Q000187:drug effects; D011247:Pregnancy; D011297:Prenatal Exposure Delayed Effects / Q000523:psychology*; D051381:Rats; D017208:Rats, Wistar; D012201:Reward; D012727:Sex Characteristics; D013997:Time Factors
chemical_list: D009294:Narcotics; D009020:Morphine