Regional adaptation of Muller cells in the chick retina. A Golgi and electron microscopical study

We report the morphological differences of Müller cells in relation to their topography, using the Golgi method. Müller cells in the central retina are long and slender, with numerous inner prolongations. In the peripheral retina, the morphology of the Müller cells adapts to the reduced thickness of the retina1 layers. In this zone, they are short and have thick inner prolongations which end in a large foot in the internal limiting membrane. In the optic disc margin, Müller cells have a particular morphology characterized by thick, arched prolongations that in general form a glial network between the retina and optic nerve. The ultrastructure of these cells is also described. The results are discussed with respect to the nature of Müller cells

A morphometric study of the secretory granules of the granular duct in the submaxillary gland of the rat following stimulation with noradrenalin and isoproterenol

In the present work, we carry out a morphometric analysis, at ultrastructural level, of the secretory granules of the granular undulated duct of the submaxillary gland of the rat, under basal conditions (Control Group or I), following stimulation for 10 minutes with 2 mg1100 g weight of Isoproterenol (Group 11), and following stimulation with 2 gamrnas/100 g weight of Noradrenalin for the same time as in the former case. It is seen that in general, Noradrenalin produces the appearance of a greater number of small granules than does Isoproterenol or the control group; and that Isoproterenol induces the presence of larger-sized granules than does Noradrenalin