Dissociation of photoreceptor cells from the pineal organ of the lamprey, Lampetra japonica

1991 ◽  
Vol 263 (3) ◽  
pp. 589-592 ◽  
Author(s):  
M. Samejima ◽  
S. Tamotsu ◽  
Y. Muranaka ◽  
Y. Morita
Keyword(s):  
Pineal Organ ◽  
Photoreceptor Cells ◽  
Lampetra Japonica

Neural elements of the pineal complex of the frog, rena esculenta, I: Centrally projecting neurons

1990 ◽  
Vol 4 (05) ◽  
pp. 389-397 ◽  
Author(s):  
Peter Ekström ◽  
Hilmar Meissl
Keyword(s):  
Pineal Organ ◽  
Photoreceptor Cells ◽  
Rana Esculenta ◽  
Projection Neurons ◽  
Pineal Complex ◽  
Bipolar Neuron ◽  
Neural Organization ◽  
Hand Functions ◽  
Frontal Organ ◽  
Pineal Tract

AbstractThe pineal complex of anuran &hibians is a directly photosensory organ, encompassing both an extracranial portion, the frontal organ, and an intracranial portion, the pineal organ proper. The projection neurons of the frontal organ respond differentially according to the wavelengths of the light stimuli. The pineal organ, on the other hand, functions mainly as a luminosity meter. Most of its centrally projecting neurons respond to all increases in ambient illumination with decreases in spontaneous firing of action potentials, although some neural units in the pineal organ may respond according to wavelength. This difference in responses to light stimulation may be reflected in the neural organization of the two parts of the pineal complex. In the present study, we have analyzed the morphology of the projection neurons of the frontal and pineal organs of the frog,Rana esculenta, by backfilling of the neurons with horseradish peroxidase through their cut axons. In the pineal organ, several types of centrally projecting neurons were observed: peripherally situated unipolar and multipolar neurons, the dendrites of which extend into a superficial axon plexus that surrounds the pineal epithelium; smaller unipolar, bipolar, or multipolar neurons situated close to the central pineal tract; and radially oriented bipolar neurons, with short dendritic processes oriented towards the lumen of the pineal organ. This latter type was strongly reminiscent of photoreceptor cells. The centrally projecting neurons of the frontal organ were multipolar, and situated in the ventral part of the organ. One photoreceptor-like bipolar neuron was observed in one frontal organ. The neurons of the frontal organ did not form a superficial plexus of neurites. This difference may relate to the different ratio of chromaticity/luminosity units in the frontal and pineal organs.

Three Kinds of Guanylate Cyclase Expressed in Medaka Photoreceptor Cells in Both Retina and Pineal Organ

1999 ◽  
Vol 255 (2) ◽  
pp. 216-220 ◽  
Author(s):  
Osamu Hisatomi ◽  
Hanayo Honkawa ◽  
Yoshikazu Imanishi ◽  
Takunori Satoh ◽  
Fumio Tokunaga
Keyword(s):  
Guanylate Cyclase ◽  
Pineal Organ ◽  
Photoreceptor Cells

Photoreceptor Cells of the Pike Pineal Organ as Cellular Circadian Oscillators

1997 ◽  
Vol 9 (4) ◽  
pp. 643-653 ◽  
Author(s):  
Valérie Bolliet ◽  
Valérie Bégay ◽  
Catherine Taragnat ◽  
Jean Paul Ravault ◽  
Jean Pierre Collin ◽  
...  
Keyword(s):  
Pineal Organ ◽  
Photoreceptor Cells ◽  
Circadian Oscillators

A quantitative morphological study of the pineal organ in the goldfish, Carassius auratus

1981 ◽  
Vol 59 (7) ◽  
pp. 1312-1325 ◽  
Author(s):  
John A. McNulty
Keyword(s):  
Endoplasmic Reticulum ◽  
Pineal Organ ◽  
Smooth Endoplasmic Reticulum ◽  
Close Association ◽  
Photoreceptor Cells ◽  
Nerve Fibers ◽  
Substantial Part ◽  
Electron Microscopic ◽  
Goldfish Carassius Auratus ◽  
Supportive Cells

Stereological techniques applied to a light and electron microscopic study of the pineal organ of the goldfish indicated that photoreceptor and supportive cells were comparable in their number and cell volume and that approximately 500 nerve cells were present in the pineal end vesicle. There were approximately 310 nerve fibers descending the distal part of the pineal tract. Quantitative analysis of organelles in photoreceptor cells revealed that the endoplasmic reticulum and Golgi bodies, in the vicinity of which were situated both clear and dense-cored vesicles, formed a substantial part of the cytoplasmic volume. Other new observations reported for this species include a close association between mitochondria and parts of the smooth endoplasmic reticulum, a characteristic feature of photoreceptor cells, and the presence of subsurface cisternae formed from profiles of endoplasmic reticulum. Moreover, specialized contacts were found between both photoreceptor and supportive cells. Some of these ultrastructural features are similar to those reported in the secretory pinealocytes of mammals. These findings suggest that (1) the pineal organ in this species has a high degree of photosensitivity as evidenced by the large number of photoreceptor cells related to each nerve cell, and (2) photoreceptor cells are metabolically active possibly having functions other than photoreception.

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