AJP - Regulatory, Integrative and Comparative Physiology, Vol 249, Issue 3 285-R289, Copyright © 1985 by American Physiological Society
Effect of pregestational sialoadenectomy of nursing mothers on eyelid opening of pups
S. Okamoto and T. Oka
The eyelid opening of pups born to and nursed by normal mice occurred by
the 15th day of birth, whereas pregestational sialoadenectomy (removal of
submandibular glands) of nursing mice delayed eyelid opening of their pups
by as much as 5 days. Parotidectomy, however, had no effect on eyelid
opening. Cross-foster nursing experiments indicated that the cause for
delayed eyelid opening of pups was to be found in sialoadenectomized
mothers, not their pups. Sialoadenectomized mothers had underdeveloped
mammary glands that produced approximately 50% less milk than controls, and
the amount of epidermal growth factor in their milk was similarly reduced.
When epidermal growth factor, a polypeptide produced by the submandibular
gland, was injected daily at a dose of 5 micrograms into sialoadenectomized
pregnant mice, the eyelid opening of the pups nursed by their mothers
occurred normally. These results are discussed with regard to the possible
role of the submandibular gland and epidermal growth factor in neonatal
eyelid opening.
