Development of rat stellate ganglion neurons containing membrane-bound muscarinic receptors and purinoreceptors.

The aim of the study reported here was to investigate the locations and morphometric characteristics of neurons in the stellate ganglion (SG) containing muscarinic cholinoreceptors and purinoreceptors in rat pups of different ages (neonatal, 10, 20, 30, 60, and 180 days) using immunohistochemical methods. The results showed that in all animals, most neurons were immunoreactive to M1 cholinoreceptors and P2X2 and P2X6 purinoreceptors from birth. Sections showed isolated neurons containing P2X3 purinoreceptors, the numbers of which increased from day 10 of life to day 20 and then decreased again. During ontogenesis, the proportions of neurons expressing M1 cholinoreceptors and P2X2 and P2X6 purinoreceptors did not change significantly. Thus, by the moment of birth, muscarinic synaptic transmission already occurred in the SG in rats, while the final set of purinoreceptors in the neurons of this sympathetic ganglion formed by age 30 days.