Mitochondrial inclusions in the snake renal tubules

The fate of intramitochondrial paracrystalline inclusion bodies in germ line cells of water frogs (Amphibia, Anura)

Numerous intramitochondrial paracrystalline inclusion bodies (ICIB) were observed in the germinal plasm of a mid-blastula, and in primordial germ cells (PGCs) after their migration to the germinal ridges, in Rana ridibunda, R. lessonae and R. esculenta. In oogonia the number of ICIB decreases rapidly. Single ICIB are observed in the germ cells up to the leptotene stage; they have never been observed in pachytene oocytes. In diplotene oocytes that have reached a diameter of about 100 microns ICIB are visible again, and their number increases concomitantly with oocyte growth.

[Giant mitochondria in the A cells of the pancreas of a lizard: Varanus niloticus]

Pancreatic A cells of the lizard Varanus niloticus are characterized by the presence of two types of mitochondria: (a) normal, small mitochondria (about 0.4 X 1 micron), and (b) giant mitochondria, measuring up to 9 micron in length and 1 micron in diameter. Giant mitochondria show various shapes. Their matrix is filled with tubules, filaments, and dense granules. Transverse sections of tubules are polygonal in shape and about 20 nm in diameter. They are grouped in bundles. The filaments, about 9-10 nm in diameter, are arranged in parallel layers crossing each other at a 57 degree angle. In a closely related species, Varanus exanthematicus, pancreatic A cells do not show these peculiar features.