TYROSINE-HYDROXYLASE MESSENGER RNA-CONTAINING NEURONS IN THE MEDIAL AMYGDALOID NUCLEUS AND THE RETICULAR NUCLEUS OF THE THALAMUS IN THE SYRIAN-HAMSTER

To confirm previous immunocytochemical findings in colchicine-treated Syrian hamsters, in situ hybridization was used to investigate the dis tribution of TH mRNA-containing cells in the medial amygdaloid nucleus (Me) and the thalamic reticular nucleus (Rt) of untreated hamsters. T H mRNA-producing neurons were observed in anterior and posterior Me an d throughout Rt, similar to the distribution of TH-immunostained cells in these areas of animals receiving colchicine. These data confirm th at TH is normally produced in amygdaloid and thalamic cell groups whic h lie outside the classical catecholamine systems.