Seasonal changes in secretory granules and crystalloid inclusions of bat thyroid parafollicular cells

E A Nunez, R P Gould, S J Holt
1970 Journal of Cell Science  
Parafollicular cells of active Autumn bats sometimes contain many large dense secretory granules (diameter 1 -2 /*m) enclosed within ribosome-studded membranes. At the same time, parafollicular cells containing small granules were often characterized by the presence of slender crystalloid rods, up to several microns in length. Parafollicular cells with large granules become depleted of them following exposure of nonhibernating bats to cold (4 °C) for 12-48 h. This treatment causes no change in
more » ... auses no change in the cells containing small granules, although partial degranulation in such cells was seen in early hibernating (November) bats. On the basis of these and previous studies it is suggested that the two types of granules in bat parafollicular cells have different fates during the animal's annual cycle of physiological activity.
pmid:5452096 fatcat:7j5mof4q25c3jefrxlnbfm2cfm