title: Gender and strain contributions to the variability of buprenorphine-related respiratory toxicity in mice.
abstract: While most deaths from asphyxia related to buprenorphine (BUP) overdose have been reported in males, higher plasma concentrations of BUP and its toxic metabolite norbuprenorphine (NBUP) have been observed in females. We previously demonstrated that P-glycoprotein (P-gp) modulation at the blood-brain barrier (BBB) contributes highly to BUP-related respiratory toxicity, by limiting NBUP entrance into the brain. In this work, we sought to investigate the role of P-gp-mediated transport at the BBB in gender and strain-related variability of BUP and NBUP-induced respiratory effects in mice. Ventilation was studied using plethysmography, P-gp expression using western blot, and transport at the BBB using in situ cerebral perfusion. In male Fvb and Swiss mice, BUP was responsible for ceiling respiratory effects. NBUP-related reduction in minute volume was dose-dependent but more marked in Fvb (p<0.01 at 1mg/kg NBUP and p<0.001 at 3 and 9mg/kg NBUP) than in Swiss mice (p<0.001 at 9mg/kg NBUP). Female Fvb mice were more susceptible to BUP than males with significantly increased inspiratory time (p<0.05) and to NBUP with significantly increased expiratory time (p<0.01). Following BUP administration, plasma BUP concentrations were significantly higher (p<0.01) and plasma NBUP concentrations significantly lower (p<0.001) in Fvb mice compared to Swiss mice. Plasma BUP concentrations were significantly higher (p<0.05) and plasma NBUP concentrations significantly lower (p<0.01) in male compared to female Fvb mice. In contrast, following NBUP administration, comparable plasma NBUP concentrations were observed in both genders and strains. No differences in P-gp expression or BUP and NBUP transport across the BBB were observed between male and female Fvb mice as well as between Swiss and Fvb mice. Our results suggest that P-gp-mediated transport across the BBB does not play a key-role in gender and strain-related variability in BUP and NBUP-induced respiratory toxicity in mice. Both gender- and strain-related differences in respiratory effects of BUP could be attributed to BUP itself rather than to its metabolite, NBUP.
authors: INSERM U705, CNRS UMR8206, Neuropsychopharmacologie des addictions, Faculté des Sciences Pharmaceutiques et Biologiques, Paris, France.
authors: Hisham
authors: H
authors: Alhaddad
authors: Salvatore
authors: S
authors: Cisternino
authors: Bruno
authors: B
authors: Saubamea
authors: Joel
authors: J
authors: Schlatter
authors: Fouad
authors: F
authors: Chiadmi
authors: Patricia
authors: P
authors: Risède
authors: Maria
authors: M
authors: Smirnova
authors: Véronique
authors: V
authors: Cochois-Guégan
authors: Nicolas
authors: N
authors: Tournier
authors: Frédéric J
authors: FJ
authors: Baud
authors: Bruno
authors: B
authors: Mégarbane
mesh_terms: D020168:ATP Binding Cassette Transporter, Subfamily B, Member 1 / Q000378:metabolism / Q000502:physiology; D000818:Animals; D001812:Blood-Brain Barrier / Q000378:metabolism; D015153:Blotting, Western; D002047:Buprenorphine / Q000633:toxicity*; D002196:Capillaries / Q000187:drug effects / Q000378:metabolism; D002560:Cerebrovascular Circulation; D004305:Dose-Response Relationship, Drug; D005260:Female; D008297:Male; D051379:Mice; D009294:Narcotics / Q000633:toxicity*; D010993:Plethysmography, Whole Body; D012131:Respiratory Insufficiency / Q000139:chemically induced* / Q000503:physiopathology; D012727:Sex Characteristics; D013045:Species Specificity
chemical_list: D020168:ATP Binding Cassette Transporter, Subfamily B, Member 1; D009294:Narcotics; D002047:Buprenorphine