Biomaterial Database

Two major tachykinins, substance P and substance K, are localized to distinct subsets of amacrine cells in the anuran retina. 2005

Dávid A Schäffer, and Robert Gábriel

MTA-PTE Adaptational Biology Research Group, Ifjúság u. 6, H-7624 Pécs, Hungary.

Tachykinins are known to be major excitatory neuromodulators in neural systems, including the retina of many vertebrate species. Among them substance P has been detected in several species, including anurans. However, none of the other major tachykinins has been sought for in the anuran retina. The aim of this study was to identify another major tachykinin, substance K (neurokinin A) in the frog retina and compare its distribution to that of substance P. Since one of the synthetic pathways of the above mentioned tachykinins make it possible to produce both peptides from one large precursor RNA, we also investigated possible colocalization with double-label immunocytochemistry. Our results show that both substance P and substance K are localized to wide-field amacrine cells in the retina of a terrestrial frog (Pelobates fuscus). Preabsorption and double-label studies provided evidence that the populations of substance P- and substance K-immunoreactive cells are clearly distinct and their dendritic arbor do not overlap in the inner plexiform layer of the retina. These findings provide evidence for the presence of (i) a novel anatomically/neurochemically identifiable amacrine cell type and (ii) predict distinct synthetic pathways for substance P and substance K in the anuran retina.

UI	MeSH Term	Description	Entries
D008297	Male		Males
D009434	Neural Pathways	Neural tracts connecting one part of the nervous system with another.	Neural Interconnections,Interconnection, Neural,Interconnections, Neural,Neural Interconnection,Neural Pathway,Pathway, Neural,Pathways, Neural
D009435	Synaptic Transmission	The communication from a NEURON to a target (neuron, muscle, or secretory cell) across a SYNAPSE. In chemical synaptic transmission, the presynaptic neuron releases a NEUROTRANSMITTER that diffuses across the synaptic cleft and binds to specific synaptic receptors, activating them. The activated receptors modulate specific ion channels and/or second-messenger systems in the postsynaptic cell. In electrical synaptic transmission, electrical signals are communicated as an ionic current flow across ELECTRICAL SYNAPSES.	Neural Transmission,Neurotransmission,Transmission, Neural,Transmission, Synaptic
D003712	Dendrites	Extensions of the nerve cell body. They are short and branched and receive stimuli from other NEURONS.	Dendrite
D005260	Female		Females
D000818	Animals	Unicellular or multicellular, heterotrophic organisms, that have sensation and the power of voluntary movement. Under the older five kingdom paradigm, Animalia was one of the kingdoms. Under the modern three domain model, Animalia represents one of the many groups in the domain EUKARYOTA.	Animal,Metazoa,Animalia
D001001	Anura	An order of the class Amphibia, which includes several families of frogs and toads. They are characterized by well developed hind limbs adapted for jumping, fused head and trunk and webbed toes. The term "toad" is ambiguous and is properly applied only to the family Bufonidae.	Bombina,Frogs and Toads,Salientia,Toad, Fire-Bellied,Toads and Frogs,Anuras,Fire-Bellied Toad,Fire-Bellied Toads,Salientias,Toad, Fire Bellied,Toads, Fire-Bellied
D013373	Substance P	An eleven-amino acid neurotransmitter that appears in both the central and peripheral nervous systems. It is involved in transmission of PAIN, causes rapid contractions of the gastrointestinal smooth muscle, and modulates inflammatory and immune responses.	Euler-Gaddum Substance P,Hypothalamic Substance P,SP(1-11),Euler Gaddum Substance P,Substance P, Euler-Gaddum,Substance P, Hypothalamic
D013569	Synapses	Specialized junctions at which a neuron communicates with a target cell. At classical synapses, a neuron's presynaptic terminal releases a chemical transmitter stored in synaptic vesicles which diffuses across a narrow synaptic cleft and activates receptors on the postsynaptic membrane of the target cell. The target may be a dendrite, cell body, or axon of another neuron, or a specialized region of a muscle or secretory cell. Neurons may also communicate via direct electrical coupling with ELECTRICAL SYNAPSES. Several other non-synaptic chemical or electric signal transmitting processes occur via extracellular mediated interactions.	Synapse
D014785	Vision, Ocular	The process in which light signals are transformed by the PHOTORECEPTOR CELLS into electrical signals which can then be transmitted to the brain.	Vision,Light Signal Transduction, Visual,Ocular Vision,Visual Light Signal Transduction,Visual Phototransduction,Visual Transduction,Phototransduction, Visual,Transduction, Visual