title: Leydig cells: octopaminergic neurons in the leech.
abstract: Leydig cells are electrically-coupled neurons in the segmental ganglia of the leech. This study reports that they stain specifically with high concentrations (0.05 mg/ml) of the dye neutral red, and that they contain octopamine, as demonstrated by radioenzymatic assay. Individual cell bodies were pooled and found to contain 0.37 pmol octopamine/cell body, giving an approximate intracellular concentration of 7.75 mM. Leydig cell bodies contain approximately 75% of the octopamine content of a segmental ganglia. Intracellular injection of large amounts of Lucifer yellow, coupled with long diffusion times, revealed a previously-undescribed Leydig cell process. The probability that Leydig cells are octopaminergic neurosecretory cells is discussed.
mesh_terms: D000200:Action Potentials; D000818:Animals; D005724:Ganglia / Q000166:cytology / Q000502:physiology; D007865:Leeches; D009474:Neurons / Q000166:cytology* / Q000502:physiology; D009655:Octopamine / Q000502:physiology*
chemical_list: D009655:Octopamine