Associate Professor
McCoy Hall 135A
Email: heiko@vetmed.wsu.edu
Telephone:(509) 335-7056
Fax: (509) 335-4650
Jansen
Lab Homepage
Research centers on investigations of the neural mechanisms
controlling seasonal reproduction and the photoperiodic control of
motivated behaviors. A complex and poorly understood interaction
between environmental and endogenous signals modulates the activity of a
subset of neurons secreting the decapeptide, gonadotropin
releasing-hormone (GnRH), to ultimately affect gamete production in both
males and females. Additional neurons in the suprachiasmatic nucleus
regulate our daily rhythms and synchronize them to the light:dark
cycle. GnRH neurons and their projections to the median eminence
represent the final common pathway in the neural control of reproduction
for all vertebrates. To ensure that young are born at favorable times,
temperate zone species have adapted a highly successful strategy of
restricting reproductive activity to limited portions of the sidereal
year. Changes in daylength (photoperiod) serve as the predominant
factor responsible for causing reproductive transitions ('Nature's
contraceptive') in many of these species. Yet, how the photoperiod
signal is conveyed to the GnRH neurons remains a key unanswered question
in the field. The bulk of evidence suggests that photoperiodic
information (via the endocrine signal for daylength - melatonin) reaches
GnRH neurons indirectly through neural inputs (afferents) from other
brain regions; these vary with season. Interestingly, changes in
daylength also modulate the expression of various motivated behaviors,
including sexual activity and drug seeking, amongst others. Our goal is
to advance a more unified hypothesis of the neural mechanisms underlying
these seasonal adaptations.
Biographical Information
Heiko T. Jansen, Associate Professor in VCAPP, received his B.A. in
Biology from Franklin Pierce College, Rindge, NH. He received both his
M.S. in Pharmacology/Toxicology (1987) and Ph.D. in Physiology (1993)
from the University of Illinois at Urbana/Champaign, IL. From 1993-1997
he did postdoctoral work at the University of Cincinnati and was awarded
an NIH post-doctoral fellowship. In 1997, he was appointed to the
faculty at the University of Cincinnati as Research Assistant Professor
and also served as a member of the Neuroscience Graduate Program. From
1997-1999, he also served as an adjunct faculty member in the Biology
Department of Xavier University. He joined the Department of VCAPP at
Washington State University and the Neuroscience Graduate Faculty in the
summer of 2000.
Recent Publications
Sleipness E, Sorg BA, and Jansen HT. 2007. Diurnal differences in
dopamine transporter and tyrosine hydroxylase levels in the rat brain:
dependence on the suprachiasmatic nucleus. Brain Res. 1129: 34-42.
Brown TE, Forquer MR, Cocking DL, Jansen HT, Harding JW and Sorg BA.
2007. Role of matrix metalloproteinases in consolidation and
reconsolidation of cocaine-induced conditioned place preference. Learn
Mem 14: 214-223.
Sleipness EP, Sorg BA, Jansen HT. 2007 Contribution of the
suprachiasmatic nucleus to day:night variation in cocaine seeking
behavior. Physiol. Behav. 91(5):523-30.
Jansen HT, Kirby JD, Cooke PS, Arambepola N, Iwamoto GA. 2007
Impact of neonatal hypothyroidism on reproduction in the male hamster,
Mesocricetus auratus. Physiol. Behav. 90: 771-81.
Sleipness EP, Sorg BA, Jansen HT. 2005 Time of day alters
long-term sensitization to cocaine in rats. Brain Res.
1065(1-2):132-7.
Jansen HT, Cutter C, Hardy S, Lehman MN, Goodman RL. (2003) Seasonal
Plasticity within the Gonadotropin-Releasing Hormone (GnRH) System of
the Ewe: Changes in Identified GnRH Inputs and Glial Association.
Endocrinology. 144(8):3663-76.
Romeo RD, Wagner CK, Jansen HT, Diedrich SL, Sisk CL. (2002)
Estradiol induces hypothalamic progesterone receptors but does not
activate mating behavior in male hamsters (Mesocricetus auratus) before
puberty. Behav Neurosci.116(2):198-205.
Vigui C, Jansen HT, Glass DG, Watanabe M, Billings HJ, Coolen LM,
Lehman MN, Karsch FJ.: (2001) Potential for PSA-NCAM-mediated
neuroplasticity within the GnRH system of the ewe. Endocrinology
142:1317-1314.
PubMed Publications (Note: PubMed Search may produce additional
"Jansen" authors.)
