The central nervous system of Limulus polyphemus: Physiological and pharmacological studies

1980 ◽  
Vol 66 (2) ◽  
pp. 121-124
Author(s):  
R.J. Walker ◽  
Victoria A. James
Keyword(s):  
Central Nervous System ◽  
Nervous System ◽  
Limulus Polyphemus ◽  
Pharmacological Studies ◽  
The Central Nervous System

scholarly journals Bacopa monnieri: Historical aspects to promising pharmacological actions for the treatment of central nervous system diseases

2022 ◽  
Vol 21 (2) ◽  
pp. 131-155
Author(s):  
Andreia Fuentes Santos ◽  
◽  
Marilia Moraes Queiroz Souza ◽  
Karoline Bach Pauli ◽  
Gustavo Ratti da Silva ◽  
...  
Keyword(s):  
Central Nervous System ◽  
Nervous System ◽  
Cognitive Processes ◽  
Biological Effects ◽  
Bacopa Monnieri ◽  
Cellular Mechanisms ◽  
Healthy Elderly ◽  
Pharmacological Studies ◽  
Gastrointestinal Side Effects ◽  
The Central Nervous System

Bacopa monnieri(L.) Wettst. (Plantaginaceae), also known as Brahmi, has been used to improve cognitive processes and intellectual functions that are related to the preservation of memory. The objective of this research is to review the ethnobotanical applications, phytochemical composition, toxicity and activity of B. monnieriin the central nervous system. It reviewed articles on B. monnieriusing Google Scholar, SciELO, Science Direct, Lilacs, Medline, and PubMed. Saponins are the main compounds in extracts of B. monnieri. Pharmacological studies showed that B. monnieriimproves learning and memory and presents biological effects against Alzheimer’s disease, Parkinson’s disease, epilepsy, and schizophrenia. No preclinical acute toxicity was reported. However, gastrointestinal side effects were reported in some healthy elderly individuals. Most studies with B. monnierihave been preclinical evaluations of cellular mechanisms in the central nervous system and further translational clinical research needs to be performed to evaluate the safety and efficacy of the plant.

Central origin of the efferent neurons projecting to the eyes of Limulus polyphemus

1991 ◽  
Vol 6 (5) ◽  
pp. 481-495 ◽  
Author(s):  
B. G. Calman ◽  
B.- A. Battelle
Keyword(s):  
Central Nervous System ◽  
Nervous System ◽  
Optic Nerve ◽  
Optic Tract ◽  
Limulus Polyphemus ◽  
Cell Of Origin ◽  
Optic Nerves ◽  
Visual Cells ◽  
Efferent Neurons ◽  
The Central Nervous System

AbstractCircadian rhythms affect the anatomy, physiology, and biochemistry of the visual cells in the eyes of the horseshoe crab (Limulus polyphemus). These rhythms are mediated by the activity of efferent neurons that project from the central nervous system to all of the eyes. In this study, the optic nerves of Limulus were backfilled with Neurobiotin revealing the location of efferent cell bodies and their projections through the central nervous system. We propose that this efferent system mediates the circadian changes in visual functions in Limulus. Whether these cells are the circadian pacemaker neurons is unknown.The cell bodies of the efferent neurons are ovoid and have a diameter of 40−80 μm. They lie within the cheliceral ganglion of the tritocerebrum, just posterior to the protocerebrum. This ganglion is on the lateral edge of the circumesophageal ring, near the middle of the dorsal-ventral axis of the ring. Each optic nerve contains axons from both ipsilateral and contralateral efferent cells, and some, possibly all, of them project bilaterally and to more than one type of optic nerve.The efferent axons form a tract that projects anteriorly from the cell bodies to the protocerebrum, and bifurcates just lateral to the protocerebral bridge. One branch crosses the midline and projects anteriorly to the optic tract and medulla on the side contralateral to the cell of origin; the other branch follows a symmetric pathway on the ipsilateral side. Small branches arising from the major efferent axons in the optic tract project through the ocellar ganglia to the median optic nerves. The efferent axons branch again in the medulla, and some of these branches innervate the ventral optic nerves. The major branches of the efferent axons continue through the lamina and enter the lateral optic nerve.

The effect of α-bungarotoxin on spontaneous activity in the ventral nerve cord of Limulus polyphemus

1981 ◽  
Vol 59 (2) ◽  
pp. 139-143 ◽  
Author(s):  
William Thomas ◽  
James G. Townsel
Keyword(s):  
Central Nervous System ◽  
Nervous System ◽  
Spontaneous Activity ◽  
Horseshoe Crab ◽  
Specific Binding ◽  
Limulus Polyphemus ◽  
Cholinergic Antagonist ◽  
The Central Nervous System ◽  
Predominant Effect ◽  
Stimulation Of

The physiological action of α bungarotoxin in the central nervous system of the horseshoe crab Limulus polyphemus was investigated. Two types of effects were produced by the toxin. The predominant effect was an inhibition of spontaneous activity. However, in some instances α bungarotoxin caused a stimulation of activity. In both cases the action of the toxin resembled the effect of d-tubocurarine and opposed the effect of carbamylcholine. Both effects of α-bungarotoxin were maximal within 15 min and were sustained for at least 2 h. These results suggest that α-bungarotoxin acts as a cholinergic antagonist in the central nervous system of Limulus and are consistent with the specific binding of the toxin to an acetylcholine receptor.

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