title: Ultrastructural Evidence of Serous Gland Polymorphism in the Skin of the Tungara Frog Engystomops pustulosus (Anura Leptodactylidae).
abstract: Three types of serous products were detected in the syncytial cutaneous glands of the leptodactylid tungara frog, Engystomops pustulosus: type Ia, granules with wide halos and variable density cores; type Ib, high density granules without halos; and type II, vesicles containing a finely dispersed product. Ultrastructural evidence revealed that these products were manufactured by different serous gland types and excluded that they represented different steps in the secretory cycle of a single gland type. Indeed, secretory maturation affecting the products released by the Golgi apparatus proceeded through different mechanisms: confluence (vesicles), interactions between syncytium and secretory product (type Ib granules), and a combination of both processes (type Ia granules). In conclusion, this investigation of secretory maturation was shown to be a suitable approach for the identification of serous gland polymorphism and demonstrated that the tungara frog belongs to the minority of anuran species characterized by this peculiar morpho-functional trait.
authors.affiliation: Dipartimento Di Biologia, Università Degli Studi Di Firenze, Florence, Italy.
authors.forename: Giovanni
authors.initials: G
authors.lastname: Delfino
authors.affiliation: Dipartimento Di Biologia, Università Degli Studi Di Firenze, Florence, Italy.
authors.forename: Filippo
authors.initials: F
authors.lastname: Giachi
authors.affiliation: Dipartimento Di Scienze Biomediche, Sperimentali E Cliniche "Mario Serio", Università Degli Studi Di Firenze, Florence, Italy.
authors.forename: Cecilia
authors.initials: C
authors.lastname: Malentacchi
authors.affiliation: Dipartimento Di Medicina Sperimentale E Clinica, Università Degli Studi Di Firenze, Florence, Italy.
authors.forename: Daniele
authors.initials: D
authors.lastname: Nosi
mesh_terms: D000818:Animals; D001001:Anura / Q000033:anatomy & histology* / Q000145:classification; D003594:Cytoplasmic Granules / Q000648:ultrastructure*; D005088:Exocrine Glands / Q000648:ultrastructure*; D046529:Microscopy, Electron, Transmission; D022142:Secretory Vesicles / Q000648:ultrastructure*; D012867:Skin / Q000648:ultrastructure*
keywords: anurans; serous cutaneous glands; ultrastructure