PHARMACOLOGIC STUDIES OF NOREPINEPHRINE ACETYLCHOLINE AND RELATED COMPOUNDS ON NEURONS IN DEITERS NUCLEUS AND CEREBELLUM

Using multibarreled electrodes, the effects of electrophoretically applied norepinephrine (NE) and acetylcholine (ACh) were studied on the lateral vestibular nucleus (NVL) neurons in cats. In contrast to most neurons in other parts of the mammalian brain, these neurons responded to NE with excitation so far as they were sensitive to the substance. This excitation was not blocked by N-(2-chloroethyl)-di-benzylamine hydrochloride or phentolamine, but was blocked by di-chloroisopropylarterenol. Isopropylarterenol, however, had no effect upon NVL neurons. ACh also excited NVL neurons and this excitation was blocked by atropine. In the cerebellum, NE exerted excitatory effects upon neurons in the flocculus while it depressed the firing of cells in the neocerebellum. The possible physiologic roles of NE and ACh excitation are discussed.