Maintenance of the Adult Rat Superior Cervical Ganglion In Vitro: Comparison of Organ and Explant Culture Systems

Abstract: Concentrations of selected intermediates of energy metabolism whole rat superior cervical ganglia maintained in vitro by an organ culture technique were compared with values measured in small slices of this maintained under essentially the same conditions. Rates of incorporation ³H]leucine into trichloroacetic acid-precipitable material in whole ganglia mained constant for at least 48 h: however, the oxidation-reduction state tissue as indexed by (NAD):(NADH) ratios calculated from measured amounts of lactate and pyruvate decreased more than 50% within ³h in vitro . Ganglion explants prepared by cutting the tissue into ³⁰⁰-pm transverse sections played (NAD):(NADH) ratios that were about three times greater than noted in whole ganglia maintained in vitro for the same period of time. explants contained significantly higher concentrations of pyruvate and α-ketoglutarate than whole ganglia maintained in culture. Maintenance of vorable metabolic state may support the extensive growth of neurites seen explant cultures of superior cervical ganglia. Outgrowth of processes containing catecholamines could be detected readily in explant cultures of ganglia adult rats; however, this was somewhat slower and less consistent than growth observed in explants from neonatal rats. Outgrowth of neurites adult ganglia was minimal without the addition of Nerve Growth Factor.