Conseguenze funzionali del trasporto di BoNT/A

Dagli studi finora condotti possiamo osservare che esiste una propagazione degli effetti della tossina, sia in senso anterogrado che retrogrado. Ci domandiamo adesso se la BoNT/A possa alterare i normali cicli di esocitosi ed endocitosi a livello sinaptico. Per far questo useremo il saggio che ho descritto nei “Risultati” (vedi il paragrafo 3.2.4): usando l’anticorpo rivolto contro il dominio luminale della sinaptotagmina è stato possibile dimostrare una captazione specifica ed attività dipendente di quest’anticorpo, evento che è ideale per lo studio di eventuali conseguenze funzionali dell’iniezione di BoNT/A. Con tale saggio sarà possibile BoNT/A

Midollo

Nocicettore dei gangli delle radici

verificare se le sinapsi contenenti SNAP-25 (e distanti dal sito di iniezione) saranno deficitarie nei cicli di eso- ed endocitosi.

Un altro approccio usato nel nostro laboratorio è stato quello di valutare l’ultrastruttura nel sito di iniezione e in sinapsi lontane. Un’osservazione è stata quella che le sinapsi intossicate hanno una densità di vescicole e una dimensione maggiore rispetto a quelle non intossicate. A questo punto ci proponiamo quindi di valutare l’ultrastruttura delle sinapsi in siti distanti dall’iniezione di BoNT/A, per comprendere se ci siano eventuali alterazioni nei cicli di eso- ed endocitosi.

B

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Ringraziamenti

Questo lavoro è stato svolto presso l’Istituto di Neuroscienze del CNR di Pisa. Il principale ringraziamento va dunque a tutti coloro che lavorano lì, ma in particolar modo al dott. Matteo Caleo a tutto il suo staff (Chiara C, Chiara R, Flavia, Laura G, Laura R, Marco e Marta): il loro contributo, la loro simpatia, umanità e disponibilità sono stati fondamentali alla realizzazione di questa tesi. Ringrazio anche il dott. Federico Cremisi e la prof.ssa Irma Nardi per la preziosa collaborazione.

Il secondo “grazie” va senza alcun dubbio alla mia famiglia ed a mio fratello Ferruccio, per aver finanziato i miei studi, aver accettato ogni mia scelta come se fosse la migliore possibile ed avermi dato tutto il loro supporto.

Ultimi per esigenza ma non per importanza, i miei amici (universitari, storici, ritrovati ed inaspettati). Senza di loro sarebbe impossibile mantenere quella buona dose di spensieratezza, sostegno ed allegria che non guasta mai. Ognuno, a suo modo, mi regala momenti importanti; ad ogni modo, fra i molti non posso non citare chi c’è davvero sempre: Emanuela, Niccolò, Carlo e Rossana. L’ultimo “grazie” va a Marco. Lui sa perché.