Studies on the eventual relationships between central oxytocin
neurotransmission and gamma-hydroxybutyrate,MDMA,are urgently needed.
Cl.
Ann N Y Acad Sci 807: 164-174 (1997)
Integrative functions of lactational hormones in social behavior and
stress
management
Carter CS, Altemus M
Department of Zoology, University of Maryland College Park 20742, USA.
For mammalian reproduction to succeed, self-defense and asociality
must be
subjugated to positive social behaviors, at least during birth,
lactation,
and sexual behavior. Perhaps the important task of regulating the
interaction between social and agonistic behaviors is managed, in
part, by
interactions between two related neurochemical systems that
incorporate
oxytocin and vasopressin in their functions. The neuropeptides
oxytocin and
vasopressin participate in important reproductive functions, such as
parturition and lactation, and homeostatic responses, including
modulation
of the adrenal axis.
Recent evidence also implicates these hormones in
social aspects of reproductive behaviors. For example, oxytocin is
important for a variety of positive social behaviors, including the
regulation of maternal-infant interactions. In adult animals, oxytocin
may
facilitate both social contact and selective social interactions
associated
with social attachment and pair bonding, and it participates in the
regulation of parasympathetic functions.
Vasopressin, in contrast, is
associated with behaviors that might be broadly classified as
"defensive"
including enhanced arousal, attention, or vigilance, increased
aggressive
behavior, and a general increase in sympathetic functions.
On the basis of
the literature on the functions of these hormones and our own recent
findings, we propose that dynamic interactions between oxytocin and
vasopressin are components of a larger system which integrates the
neuroendocrine and autonomic changes associated with mammalian social
behaviors and the concurrent regulation of the stress axis.
In addition,
studies of lactating females provide a valuable model for
understanding the
more general neuroendocrinology of the stress axis. Peptide hormones,
including oxytocin and vasopressin, do not readily cross the
blood-brain
barrier and must be administered centrally (i.c.v.) to reach the
brain.
Nasal sprays have been used to promote milk let down and have been
used in
some behavioral studies, but the extent to which such compounds reach
the
brain is not known.
Therefore, virtually nothing is known regarding the
effects in humans of centrally administered oxytocin.................
The study of human
lactation, in conjunction with animal research, provides an
opportunity to
begin to develop viable hypotheses regarding the behavioral effects of
oxytocin.
PMID: 9071349, MUID: 97224976
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