Adrenergic nerves to the rat parotid gland originating in the contralateral sympathetic chain.

The parotid gland of the rat seems to receive some adrenergic nerves from the sympathetic chain of the opposite side. This is suggested by the following evidence: after unilateral removal of the superior cervical ganglion, parotid tissue from the contralateral gland shows degeneration secretion of amylase in vitro similar to, but much smaller than that known to occur ipsilaterally. When parotid secretion is evoked parasympathetically in the anesthetized rat, superimposed stimulation of the contralateral cervical sympathetic trunk can be shown to increase the secretion of amylase into this parasympathetic saliva; as it does, much more, ipsilaterally. It may also cause an evanescent decrease of the salivary flow, suggesting that not only secretory, but also vasoconstrictor nerves had been activated. After removal of one sympathetic ganglion, some undergenerated adrenergic nerves remain ipsilaterally, as earlier demonstrated; but no such fibers can be detected when the ganglion has been removed on both sides.