Ekström J, Kemplay S K, Garrett J R, Duchen L W
Experientia. 1977 Nov 15;33(11):1458-60. doi: 10.1007/BF01918806.
The choline acetyltransferase activity of submandibular glands that had previously received a retrograde injection of botulinum toxin via their ducts was found to be markedly lower than in the untreated contralateral glands. In the parotid glands exposed to the same treatment the activity of this enzyme was less affected.