Serotoninergic and enkephalinergic cell groups in the reticular formation of the bat ray and two skates.

Title

Serotoninergic and enkephalinergic cell groups in the reticular formation of the bat ray and two skates.

Creator

Stuesse S L; Cruce W L; Northcutt R G

Publisher

Brain, behavior and evolution

Date

1991
1991

Description

The distribution of cells which were immunohistochemically positive for leu-enkephalin (LENK+) or serotonin (5-HT+), two substances widely distributed in the reticular formation, was determined in two species of skates (Raja binoculata and Raja rhina) and a bat ray (Myliobatis californica). The Rajoids are closely related to the Rhinobatoids which contains Platyrhinoidis, an elasmobranch that does not have a nucleus raphe dorsalis. Myliobatis was chosen for an outgroup comparison. Most of the nuclei that were 5-HT+ were also LENK+. The greatest number of labeled cells was in the hypothalamus bordering the third ventricle and in the neurointermediate lobe of the pituitary. The mesencephalon was rich in cells in the ventral tegmental area bordering the red nucleus. In both genera, there were numerous 5-HT+ and LENK+ fusiform cells paralleling the ventral surface of the metencephalon and myelencephalon. These cells were located in several reticular nuclei but were especially prominent in nucleus reticularis (n.r.) pontis oralis, n.r. magnocellularis, and n.r. paragigantocellularis lateralis. The latter nucleus contained fewer LENK+ than 5-HT+ cells. In both genera, 5-HT+ and LENK+ cells were located in raphe pallidus, raphe obscurus, raphe magnus, raphe centralis superior, and raphe linearis. Minor differences in distribution of the remaining 5-HT+ and LENK+ cell groups were found, but these representative elasmobranchs lack a dorsal raphe nucleus which, in mammals, is the largest serotoninergic group.

Subject

Animals; Brain Mapping; Diencephalon/anatomy & histology/physiology; Enkephalin; Immunoenzyme Techniques; Leucine/*physiology; Mesencephalon/anatomy & histology/physiology; Neurons/physiology; Reticular Formation/anatomy & histology/*physiology; Serotonin/*physiology; Skates (Fish)/*physiology; Species Specificity; Spinal Cord/anatomy & histology/physiology

Identifier

Rights

Article information provided for research and reference use only. All rights are retained by the journal listed under publisher and/or the creator(s).

Pages

39–52

Issue

1

Volume

38

Citation

Stuesse S L; Cruce W L; Northcutt R G, “Serotoninergic and enkephalinergic cell groups in the reticular formation of the bat ray and two skates.,” NEOMED Bibliography Database, accessed April 22, 2024, https://neomed.omeka.net/items/show/4724.