title: Transcription and protein synthesis inhibitors influence long-term effects of acetyl-l-carnitine on non-associative learning in the leech.
abstract: Acetyl-l-carnitine (ALC) is the principal acetyl ester of L-carnitine and it plays an essential role in intermediary metabolism. ALC affects several targets in the nervous system. Along this line of investigation, we analyzed the long-term effects of ALC on elementary nonassociative learning in the swimming induction model of the leech Hirudo medicinalis, in which nociceptive stimulation of the dorsal skin produces a more rapid swim response to a test stimulus (sensitization). In this simplified model a single ALC administration blocked the sensitizing effects of nociceptive stimulation in swim induction showing increasingly long lasting effects. Herein, we have analyzed the long-term effects of ALC on sensitization and dishabituation. Leeches were treated with inhibitors of either transcription or protein synthesis 30 min after the administration of ALC and, subsequently, subjected to noxious stimuli: the animals exhibited a sensitized swimming response 6 days after ALC treatment but not after 2 hours indicating that the long-term suppressive effects of ALC on sensitization/dishabituation needed mRNA and protein synthesis.
authors.affiliation: Dipartimento di Scienze Farmaceutiche, Università degli Studi di Perugia, Perugia 06126, Italy. Electronic address: giovanna.traina@unipg.it.
authors.forename: Giovanna
authors.initials: G
authors.lastname: Traina
authors.affiliation: Dipartimento di Ricerca Traslazionale e delle Nuove Tecnologie in Medicina e Chirurgia, Università di Pisa, Pisa 56127, Italy.
authors.forename: Rossana
authors.initials: R
authors.lastname: Scuri
mesh_terms: D000108:Acetylcarnitine / Q000494:pharmacology*; D000818:Animals; D007858:Learning / Q000187:drug effects* / Q000502:physiology; D007865:Leeches; D011500:Protein Synthesis Inhibitors / Q000494:pharmacology*; D013550:Swimming / Q000502:physiology / Q000523:psychology; D013997:Time Factors; D014158:Transcription, Genetic / Q000187:drug effects* / Q000502:physiology
chemical_list: D011500:Protein Synthesis Inhibitors; D000108:Acetylcarnitine
keywords: Acetyl-l-carnitine; Dishabituation; Leech; Protein synthesis; Sensitization; Swimming induction