Sensory systemCulture conditions determine the prevalence of bipolar and monopolar neurons in cultures of dissociated spiral ganglion
Section snippets
Animals
Newborn and postnatal day 1 mice, CD-1 strain (Charles River Laboratories, Wilmington, MA, USA) were used. The care and use of the animals in this study were carried out in accordance with the NIH Guide for the Care and Use of Laboratory Animals and was approved by the Animal Care and Use Committee of Northwestern University. Every effort was made to minimize the suffering of research animals and to limit their numbers.
Cell culture
Cultures of dissociated spiral ganglion in 96-well plates were prepared as
Results
We previously demonstrated that neuronal survival 42 h after plating could be increased when LIF was added to the control conditions of BDNF+NT3+serum. This additional survival in LIF cultures was associated with an increase in the absolute number of bipolar neurons over that in control cultures (Whitlon et al., 2006). Signaling by LIF is known to be initiated at the cell surface through the LIFRβ-gp130 receptor. To determine if other cytokines that are known to function through the LIFRβ-gp130
Discussion
In this study, we have exposed spiral ganglion cultures to neurotrophins, LIF-type cytokines and BMP4 and examined the resulting neuronal survival, morphology and neurite lengths. Under all conditions, monopolar neurons, bipolar neurons and neurons with no neurites comprise over 95% of the neurons in the culture. However, the relative contributions of the different morphologies differ between control, LIF and BMP4 conditions. Specifically, as compared with control, inclusion of LIF type
Acknowledgments
The authors appreciate the advice of Dr. Adriana Ferreira on neuronal cell cultures. We thank Dr. Ferreira, Dr. James Bartles and Dr. David Tieu for their insightful comments on the manuscript. This work was supported by NIH grant #DC00653.
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