title: Abrupt changes in pentobarbital sensitivity in preBötzinger complex region, hypoglossal motor nucleus, nucleus tractus solitarius, and cortex during rat transitional period (P10-P15).
abstract: On postnatal days P10-P15 in rat medulla, neurotransmitter receptor subunit composition shifts toward a more mature phenotype. Since medullary GABAARs regulate cardiorespiratory function, abrupt alterations in GABAergic synaptic inhibition could disrupt homeostasis. We hypothesized that GABAARs on medullary neurons become more resistant to positive allosteric modulation during P10-P15. Medullary and cortical slices from P10 to P20 rats were used to record spontaneous action potentials in pre-Botzinger Complex (preBötC-region), hypoglossal (XII) motor nucleus, nucleus tractus solitarius (NTS), and cortex during exposure to pentobarbital (positive allosteric modulator of GABAARs). On P14, pentobarbital resistance abruptly increased in preBötC-region and decreased in NTS, but these changes in pentobarbital resistance were not present on P15. Pentobarbital resistance decreased in XII motor nucleus during P11-P15 with a nadir at P14. Abrupt changes in pentobarbital resistance indicate changes in GABAergic receptor composition and function that may compensate for potential increased GABAergic inhibition and respiratory depression that occurs during this key developmental transitional period.
authors.affiliation: Department of Comparative Biosciences, School of Veterinary Medicine, University of Wisconsin, Madison, WI 53706, United States.
authors.forename: Sara M F
authors.initials: SM
authors.lastname: Turner
authors.affiliation: Department of Comparative Biosciences, School of Veterinary Medicine, University of Wisconsin, Madison, WI 53706, United States. Electronic address: johnsons@svm.vetmed.wisc.edu.
authors.forename: Stephen M
authors.initials: SM
authors.lastname: Johnson
mesh_terms: D000200:Action Potentials / Q000187:drug effects; D000367:Age Factors; D000818:Animals; D000831:Animals, Newborn; D002540:Cerebral Cortex / Q000166:cytology / Q000187:drug effects / Q000254:growth & development; D006993:Hypnotics and Sedatives / Q000494:pharmacology*; D066298:In Vitro Techniques; D009434:Neural Pathways / Q000187:drug effects / Q000502:physiology; D009474:Neurons / Q000187:drug effects* / Q000502:physiology; D010424:Pentobarbital / Q000494:pharmacology*; D051381:Rats; D017208:Rats, Wistar; D012125:Respiratory Center / Q000166:cytology / Q000187:drug effects / Q000254:growth & development; D017552:Solitary Nucleus / Q000166:cytology / Q000187:drug effects / Q000254:growth & development; D013997:Time Factors
chemical_list: D006993:Hypnotics and Sedatives; D010424:Pentobarbital
keywords: Development; Hypoglossal; Nucleus tractus solitaries; Pentobarbital; preBotzinger complex