Frog stomach enteric plexuses in culture: isolation, morphological characterization and bioelectrical recordings

Area of Science:

• Gastroenterology
• Neuroscience
• Amphibian Biology

Background:

• The enteric nervous system (ENS) regulates gastrointestinal function.
• Studying ENS in amphibians presents unique challenges due to cellular osmolarity requirements.

Purpose of the Study:

• To isolate, culture, and characterize Rana ridibunda stomach enteric plexuses.
• To assess the viability of bioelectric recordings from cultured amphibian enteric plexuses.
• To establish a foundation for studying amphibian gastrointestinal neurotransmission.

Main Methods:

• Isolation and culture of Rana ridibunda stomach enteric plexuses using modified Eagle MEM.
• Collagenase digestion and culture conditions adapted for amphibian osmolarity (70% dilution).
• Morphological characterization via phase contrast microscopy, acetylcholinesterase, and fluorescence staining (OsO4-ZnI2, PFA).
• Intra- and extracellular bioelectric recordings from cultured explants.

Main Results:

• Successful isolation and culture of amphibian enteric plexuses were achieved.
• Morphological analysis revealed distinct neuron types (pyramidal, bipolar, aligned oval somas).
• Bioelectric recordings confirmed the preservation of neuronal membrane electrophysiological properties in culture.
• Methods demonstrated consistency across different staining techniques.

Conclusions:

• The established culture conditions maintain the viability and electrophysiological integrity of frog enteric neurons.
• This model system is suitable for further investigation into amphibian gastrointestinal neurotransmitters and synaptic function.