Abstract
Substance P-like immunoreactivity (SPLI) and methionine-enkephalinlike immunoreactivity (MELI) were determined in salivary glands from rats by radioimmunoassay. In all salivary glands investigated (submandibular gland, sublingual gland and parotid gland), SPLI and MELI were detected. The amount of both peptides is comparable to or relatively higher than those found in any other peripheral tissue. The level of SPLI showed a tendency to increase following chronic treatment with morphine; the enhancement in the submandibular gland and the sublingual gland was especially remarkable. The level of MELI was decreased, particularly in the submandibular gland.
