Scanning electron microscopy of the wall of the third ventricle of the brain of Rana temporaria. III. Electron microscopy of the ventricular surface of the median eminence

The Neurosecretory System Is Hypertrophied in Senescence-Accelerated Mice

The hypothalamic supraoptic and paraventricular nuclei form the neurosecretory system and synthesize the neurohormones oxytocin and arginine-vasopressin. The senescence-accelerated mouse is a model of rapid aging that displays senile amyloidosis and memory problems. This paper presents the characterization of the neurosecretory system and describes the presence of a bilateral constant cluster of neurosecretory neurons in these mice. The stereologic analysis revealed that these groups contain 197 +/- 18 cells (87% synthesize arginine-vasopressin and 13% oxytocin). The presence of these clusters of neurosecretory neurons suggests that these mice could present greater neurohormone synthesis, increasing the deleterious effects of accelerated aging in this strain.

Scanning electron microscopy of central nervous system cerebrospinal-fluid-contacting surfaces: a bibliography (1963-1995)

This bibliography is compiled to assist in locating papers related to the application of scanning electron microscopy (SEM) to cerebrospinal-fluid-contacting surfaces in vertebrates. The use of SEM by neuroscientists has continued apace since the publication of the first bibliography in 1980. SEM studies now include more than 50 species of vertebrates and range from cyclostomes to humans; they encompass development from embryo to senescence and concern both normal and pathologic morphology. Although remarkable strides have been made toward a greater understanding of many aspects of the structure and function of cerebrospinal-fluid-contacting surfaces, many significant problems await the judicious application of scanning electron microscopy.

Purification of viable ciliated cuboidal ependymal cells from rat brain

Trypsinization of coronal sections of rat brain, followed by incubation with the chelating agent, ethyleneglycol-bis(beta-aminoethyl ether)-N,N'-tetraacetic acid (EGTA), results in selective release of ciliated cuboidal ependymal cells which may be further purified by centrifugal methods. The isolated cells are motile, viable, and exhibit ultrastructure comparable to that in situ.

Specializations of the ependyma in the third ventricle of the developing hamster

Ependymal cells in the region of the hypothalamic sulcus, hypothalamus, infundibular recess and supraoptic recess exhibit large apical protrusions between day 12 and day 14 post coitus. The ependyma was examined using light microscopy and transmission and scanning electron microscopy. The protrusions contain ribosomes and cytoplasmic matrix. Occasionally other cytoplasmic organelles were found within the protrusions. The protrusions range in shape from a rounded elevation of the apical surface of the ependymal cell to spherical bodies attached to cell surface by a slender stalk. The unique transitory specialization of the ependyma may represent either a neurosecretory or mechanical folding mechanism.