Colloid resorption in thyroid glands as revealed by scanning electron microscopy. 1978

A Lupulescu

Colloid resorption from thyroid follicles in control and in calcitonin-treated rabbits was studied with the scanning electron microscope. Thus, an intense cell surface activity with several vesicles (exocytotic vesicles) and large pseudopods, sometimes cylindroids, is predominant on the thyroid follicular cells of calcitonin-treated rabbits. The pseudopods are irregular, mostly elongated, cup or dome-shaped and operate by phagocytosis or engulfment of colloid droplets (endocytosis). Only microvilli are visible on the cell surface of thyroid follicles in control rabbits. Comparative ultrastructural studies also revealed the occurrence of small exocytotic vesicles and large pseudopods in thyroid glands stimulated by calcitonin. The present findings demonstrate that the scanning electron microscopy better visualizes the colloid resorption and provides more details for the role of follicular cell surface in thyroid physiology.

UI MeSH Term Description Entries
D008297 Male Males
D008855 Microscopy, Electron, Scanning Microscopy in which the object is examined directly by an electron beam scanning the specimen point-by-point. The image is constructed by detecting the products of specimen interactions that are projected above the plane of the sample, such as backscattered electrons. Although SCANNING TRANSMISSION ELECTRON MICROSCOPY also scans the specimen point by point with the electron beam, the image is constructed by detecting the electrons, or their interaction products that are transmitted through the sample plane, so that is a form of TRANSMISSION ELECTRON MICROSCOPY. Scanning Electron Microscopy,Electron Scanning Microscopy,Electron Microscopies, Scanning,Electron Microscopy, Scanning,Electron Scanning Microscopies,Microscopies, Electron Scanning,Microscopies, Scanning Electron,Microscopy, Electron Scanning,Microscopy, Scanning Electron,Scanning Electron Microscopies,Scanning Microscopies, Electron,Scanning Microscopy, Electron
D010587 Phagocytosis The engulfing and degradation of microorganisms; other cells that are dead, dying, or pathogenic; and foreign particles by phagocytic cells (PHAGOCYTES). Phagocytoses
D011817 Rabbits A burrowing plant-eating mammal with hind limbs that are longer than its fore limbs. It belongs to the family Leporidae of the order Lagomorpha, and in contrast to hares, possesses 22 instead of 24 pairs of chromosomes. Belgian Hare,New Zealand Rabbit,New Zealand Rabbits,New Zealand White Rabbit,Rabbit,Rabbit, Domestic,Chinchilla Rabbits,NZW Rabbits,New Zealand White Rabbits,Oryctolagus cuniculus,Chinchilla Rabbit,Domestic Rabbit,Domestic Rabbits,Hare, Belgian,NZW Rabbit,Rabbit, Chinchilla,Rabbit, NZW,Rabbit, New Zealand,Rabbits, Chinchilla,Rabbits, Domestic,Rabbits, NZW,Rabbits, New Zealand,Zealand Rabbit, New,Zealand Rabbits, New,cuniculus, Oryctolagus
D002116 Calcitonin A peptide hormone that lowers calcium concentration in the blood. In humans, it is released by thyroid cells and acts to decrease the formation and absorptive activity of osteoclasts. Its role in regulating plasma calcium is much greater in children and in certain diseases than in normal adults. Thyrocalcitonin,Calcitonin(1-32),Calcitrin,Ciba 47175-BA,Eel Calcitonin,Calcitonin, Eel,Ciba 47175 BA,Ciba 47175BA
D003102 Colloids Two-phase systems in which one is uniformly dispersed in another as particles small enough so they cannot be filtered or will not settle out. The dispersing or continuous phase or medium envelops the particles of the discontinuous phase. All three states of matter can form colloids among each other. Hydrocolloids,Colloid,Hydrocolloid
D004705 Endocytosis Cellular uptake of extracellular materials within membrane-limited vacuoles or microvesicles. ENDOSOMES play a central role in endocytosis. Endocytoses
D005089 Exocytosis Cellular release of material within membrane-limited vesicles by fusion of the vesicles with the CELL MEMBRANE.
D000818 Animals Unicellular or multicellular, heterotrophic organisms, that have sensation and the power of voluntary movement. Under the older five kingdom paradigm, Animalia was one of the kingdoms. Under the modern three domain model, Animalia represents one of the many groups in the domain EUKARYOTA. Animal,Metazoa,Animalia
D013961 Thyroid Gland A highly vascularized endocrine gland consisting of two lobes joined by a thin band of tissue with one lobe on each side of the TRACHEA. It secretes THYROID HORMONES from the follicular cells and CALCITONIN from the parafollicular cells thereby regulating METABOLISM and CALCIUM level in blood, respectively. Thyroid,Gland, Thyroid,Glands, Thyroid,Thyroid Glands,Thyroids

Related Publications

Copied contents to your clipboard!