In all major groups of Australian marsupials, prostaglandin F2α (PGF) or oxytocin injection initiates birth behavior in adult females, adult males and pouch young. Because inhibitors of PGF synthesis block this initiation, oxytocin may activate birth behavior via the stimulation of PGF synthesis. In this study, the role of PGF and oxytocin in the activation of birth behavior was examined in an American marsupial, the gray short-tailed opossum (Monodelphis domestica). Adult male and female gray opossums were given PGF, oxytocin, or saline (control) before behavioral observation. On the next day, the animals in the oxytocin group were injected with the PGF inhibitor flunixin meglumide (Finadyne, Schering Corp., U.S.A.) before oxytocin reinjection and behavioral observation. Both males and females showed birth behavior in response to PGF but only females responded to oxytocin. There was no significant difference in the latency of response of females to oxytocin alone versus response to oxytocin after receipt of the PGF inhibitor. These results suggest that, in contrast to Australian species, in this American marsupial, oxytocin initiates birth behavior only in females and does not operate via stimulation of prostaglandin secretion. (C) 2000 Academic Press.

Item Type:	Refereed Article
Research Division:	Agricultural, Veterinary and Food Sciences
Research Group:	Agricultural biotechnology
Research Field:	Agricultural molecular engineering of nucleic acids and proteins
Objective Division:	Expanding Knowledge
Objective Group:	Expanding knowledge
Objective Field:	Expanding knowledge in the environmental sciences
UTAS Author:	Rose, RW (Associate Professor Randy Rose)
ID Code:	19713
Year Published:	2000
Web of Science® Times Cited:	17
Deposited By:	Zoology
Deposited On:	2000-08-01
Last Modified:	2011-08-04
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