[Development of rat stellate ganglion neurons, containing membrane muscarinic and purinoreceptors].

The aim of this study was to determine the localization and morphometric characteristics of the stellate ganglion (SG) neurons containing muscarinic and purinoreceptors in rats of different ages (newborn, 10-, 20-, 30-, 60-, and 180-day-old) using the immunocytochemical methods. The results obtained indicated that in all the animals studied, the major part of neurons contained immunopositive P2X2, P2X6 purinoreceptors and M1 cholinoreceptors since birth onwards. A few of the neurons containing P2X3 purinoreceptors were detected in all the stages of postnatal development; these neurons were scarce in rats up to 10 days of life, after which their number increased to reach a maximal value in 20-day-old animals and then declined again. No significant changes were found in the proportion of neurons expressing M1 cholinoreceptors and P2X2, P2X6 purinoreceptors during the ontogenesis. Thus, the muscarinic synaptic transmission was already present in SG of rats by the time of their birth, while the final set of purinoreceptors on the neurons of sympathetic ganglion was formed by the age of 30 days.