È stata determinata la concentrazione degli aminoacidi liberi nel contenuto intestinale, negli enterociti e nell'emolinfa delle larve mature dei Lepidotteri Philosamia cynthia e Bombyx mori. Gli aminoacidi neutri e basici sono più concentrati nell'emolinfa che nel lume intestinale, il che suggerisce un ruolo attivo dell'intestino nel loro assorbimento. Inoltre, dai rapporti tra le concentrazioni cellula/lume e emolinfa/cellula, si può ipotizzare che a livello della membrana luminale sia localizzato un meccanismo attivo di trasporto per gli aminoacidi neutri, e che a livello della membrana basolaterale sia localizzato un meccanismo attivo di trasporto per gli aminoacidi basici.
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Con il contributo del Ministero per i Beni e le Attività Culturali