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E G Espinal

Publications and source records attributed to E G Espinal.

10 recordsLinked to original sources
PubMed1985

Scanning electron microscopy of human submandibular gland.

The fracture surface of human submandibular gland analyzed by scanning electron microscopy is studied here. Acini showed spherical granules of 0.7 +/- 0.28 micron diameter, their most distinctive feature. Some empty, septate cavities found contiguous to serous acini were considered to be mucous acini. Striated ducts had a circular lumen, with microvilli forming prominences. Blebs, some intact and others ruptured, were interpreted as apocrine secretion. The 'separating zone' of the striated cells was distinguishable from the rest of the cell because the structure of the cell was granular whereas the 'separating zone' was fibrillar.

Adult↗
PubMed1985

Changes in the vascular bed of submandibular glands after chronic autonomic denervation.

The effect of chronic sympathetic denervation (SCG) or parasympathetic decentralization (PSD) on the vascularization of the submaxillary gland (SM) of rat was studied in connection with morphological and functional changes. The resection of the superior cervical ganglion or the section of the chorda tympani was performed in adult male Wistar rats prior to the injection of Microfil MV Orange 3.25 cm3/kg. Once dissected, the glands were made transparent in increasing concentrations of methyl salicylate--alcohol. Three longitudinal sections were performed and the central one was projected in an automatic image analyzer (Kontron Zeiss), where vascular length and vascular volume were measured. Another group of animals was injected with Microfil after having received an injection of noradrenaline (10 g/kg) in SCG glands and methacholine in PSD glands. In SCG glands, vascular length underwent a 60% increase and the vascular volume increased from 0.26 +/- 0.15 cu mm/cu mm in controls to 0.54 +/- 0.15 cu mm/cu mm in SCG. The intravenous administration of noradrenaline prior to Microfil injection reverted the phenomenon. PSD caused a reduction of the vascular bed which resulted mainly in increased vascular volume. The administration of methacholine (10 g/kg) reverted the-response. It was concluded that SCG induced a loss of the existing vasoconstrictor tone, thus causing increase of vascular length and volume (passive vascular dilatation). Increased vascular volume after chronic PSD is compatible with vascular stasis and the absence of variations in vascular volume after the injection of methacholine would indicate that in the SM glands of rats there is no vascular dilatation tone.

Animals↗
PubMed1984

Salivary gland tumors induced by 32P.

The oncogenic power of 32P was demonstrated in salivary glands. An intraglandular injection of 0.25 mCi of chromic colloidal phosphate (32P) was administered to young adult Wistar rats. Seven months post-injection, tumors began to appear in the neck region in 64% of the rats. The tumors were sarcomas (50%), carcinomas (35.70%), and carcino-sarcomas (14.28%).

Animals↗
PubMed1983

Freeze-fracture surface of salivary glands of rat observed by scanning electron microscopy.

The structure of parenchymal components of rat submandibular glands observed with scanning electron microscopy is presented. The glands were fixed, submerged in liquid nitrogen, cryofractured, dehydrated and critical-point-dried. The fracture surface displayed the acini, granular ducts and striated ducts. Acini exhibit a typical sponge-like pattern of irregular and empty cavities. Granular ducts are lined by bulging cells laden with numerous secretory granules. Their diameter ranged from 0.2 to 3.2 microns, with a mean value of 1.240.4 microns. Measurement of the actual granules was rendered possible by direct observation. Striated ducts exhibited a cribiform pattern near the basal cell region which corresponds to infoldings of the basal cell membrane.

Animals↗
PubMed1983

Radiation effects on submandibular gland of the rat. Stereological and ultrastructural study.

The chronic effect of 2000 rd (20 Gy) of X-rays locally applied to the submandibular gland of Wistar young-adult male rats, was studied by stereology, and light and electron microscopic observations. They demonstrated that degenerative changes were observed during the first months after irradiation. Atrophic processes developed from 6 months onwards. In the acinar compartment, atrophy was progressive from the first months post-irradiation up to 9 months post-irradiation. Ductal cell membranes and mitochondrial damage were clearly detected at ultrastructural level. Nuclear fragmentation and secretory granules alterations were also frequently seen in the acinar compartment.

Animals↗