Alpha-melanocyte-stimulating hormone infusions during pregnancy in the rat: effects on offspring weight, pain reactivity and sexual behavior.
Pregnant rats treated during the last third of pregnancy with a continuous infusion of alpha-melanocyte-stimulating hormone (alpha-MSH) produced offspring that weighed less at birth and in adulthood. These offspring of the alpha-MSH treated mothers were less sensitive to pain and as adults showed a reduced analgesic response to morphine. Male offspring of alpha-MSH treated mothers and of control animals responded similarly in sexual performance tests, except that the treated animals significantly shifted their pattern of responding when they encountered a new testing arena or experienced defeat. The offspring of alpha-MSH treated mothers were influenced more by changes in their environment than were control offspring. These effects are similar to those reported following perinatal treatment with opiate drugs or peptides.
Martin
J T
JT
College of Osteopathic Medicine of the Pacific, Pomona, California 91766-1889.
Bradshaw
W
W
Miczek
K
K
Baum
M J
MJ
D000375:Aging; D000818:Animals; D000831:Animals, Newborn; D001724:Birth Weight / Q000187:drug effects*; D001835:Body Weight / Q000187:drug effects; D005260:Female; D008297:Male; D010146:Pain / Q000503:physiopathology*; D011247:Pregnancy; D011270:Pregnancy, Animal / Q000187:drug effects*; D051381:Rats; D012737:Sex Factors; D012726:Sexual Behavior, Animal / Q000187:drug effects*; D000521:alpha-MSH / Q000494:pharmacology*
D000521:alpha-MSH