AJP - Endocrinology and Metabolism, Vol 253, Issue 3 E251-E254, Copyright © 1987 by American Physiological Society
Long-latency growth-promoting activity of EGF when administered to mice at the neonatal stage
O. Imada, N. Hayashi, K. Masamoto, S. Kasuga, T. Fuwa and S. Nakagawa
The effect of biosynthetic human epidermal growth factor (Bh-EGF) as well
as mouse EGF on postnatal development of mice of ICR strain was examined.
Daily administration of Bh-EGF (0.01, 0.1, and 1.0 microgram X g body wt-1
X day-1) for 30 consecutive days postpartum caused a clearly dose-dependent
increase in their body weight. Furthermore, in addition to the well-known
premature eyelid opening and early tooth eruption, we have also observed
precocious opening of the vagina among treated females. As far as the
accelerated growth rate as reflected in their body weight gain was
concerned, daily administration for only five consecutive days postpartum
was just as effective as the above noted 30 consecutive daily injections.
As to the precocious vaginal opening, however, the susceptible 5-day-period
was found to be 14-18 days after the parturition. Some of those treated
females also entered the estrous cycle precociously, a few days after the
precocious opening of their vagina. The microscopic examination of various
organs from treated males and females revealed no apparent pathological
changes. As far as the above noted effects of EGF were concerned, Bh-EGF,
which is xenogenic to mice, was as potent as mouse EGF.
