PERIPHERAL PROJECTIONS OF CALRETININ-IMMUNOREACTIVE PRIMARY SENSORY NEURONS IN CHICK HINDLIMBS

In chicken dorsal root ganglia, calretinin immunoreactivity is express ed by a subpopulation of large A-neurons, most of which co-express cal bindin D-28k. The myelinated axons of these neurons selectively innerv ate all muscle spindles and most Herbst corpuscles associated to feath ers in hindlimbs. It is suggested that the presence of calretinin in p rimary afferents may be correlated with the electrophysiological prope rties of rapidly adapting mechanoreceptors.