Substance P-like immunoreactivity in sympathetic ganglion from toad

Area of Science:

• Neuroscience
• Cell Biology
• Pharmacology

Background:

• Substance P is a neuropeptide implicated in various physiological processes.
• Sympathetic ganglia play a crucial role in the autonomic nervous system.
• The presence and function of Substance P in amphibian sympathetic ganglia are not fully understood.

Purpose of the Study:

• To investigate the localization of Substance P-like immunoreactivity in toad sympathetic ganglia.
• To determine the effect of Substance P on synaptic transmission in these ganglia.

Main Methods:

• Immunohistochemistry was used to identify Substance P-like immunoreactive cells.
• Electrophysiological recordings were performed to assess synaptic transmission.
• Experiments were conducted on normal and capsaicin-treated sympathetic ganglia of Caudiverbera caudiverbera.

Main Results:

• Substance P-like immunoreactivity was found in mast cells and SIF (small intensely fluorescent) cells in the eighth sympathetic ganglion.
• Application of Substance P (0.001-0.003 mM) increased the compound action potential.
• Substance P enhanced both tetanic stimulation and post-tetanic potentiation, indicating facilitation of synaptic transmission.

Conclusions:

• Substance P is present in specific cell types within toad sympathetic ganglia.
• Substance P acts as a facilitator of synaptic transmission in the sympathetic ganglia of Caudiverbera caudiverbera.