Cocaine- and amphetamine-regulated transcript is present in hypothalamic neuroendocrine neurones and is released to the hypothalamic-pituitary portal circuit
Research output: Contribution to journal › Journal article › Research › peer-review
Standard
Cocaine- and amphetamine-regulated transcript is present in hypothalamic neuroendocrine neurones and is released to the hypothalamic-pituitary portal circuit. / Larsen, P J; Seier, V; Fink-Jensen, A; Holst, Jens Juul; Warberg, J; Vrang, N.
In: Journal of Neuroendocrinology, Vol. 15, No. 3, 03.2003, p. 219-26.Research output: Contribution to journal › Journal article › Research › peer-review
Harvard
APA
Vancouver
Author
Bibtex
}
RIS
TY - JOUR
T1 - Cocaine- and amphetamine-regulated transcript is present in hypothalamic neuroendocrine neurones and is released to the hypothalamic-pituitary portal circuit
AU - Larsen, P J
AU - Seier, V
AU - Fink-Jensen, A
AU - Holst, Jens Juul
AU - Warberg, J
AU - Vrang, N
PY - 2003/3
Y1 - 2003/3
N2 - Cocaine- and amphetamine-regulated transcript (CART) is present in a number of hypothalamic nuclei. Besides actions in circuits regulating feeding behaviour and stress responses, the hypothalamic functions of CART are largely unknown. We report that CART immunoreactivity is present in hypothalamic neuroendocrine neurones. Adult male rats received a systemic injection of the neuronal tracer Fluorogold (FG) 2 days before fixation, and subsequent double- and triple-labelling immunoflourescence analysis demonstrated that neuroendocrine CART-containing neurones were present in the anteroventral periventricular, supraoptic, paraventricular (PVN) and periventricular nuclei of the hypothalamus. In the PVN, CART-positive neuroendocrine neurones were found in all of cytoarchitectonically identified nuclei. In the periventricular nucleus, approximately one-third of somatostatin cells were also CART-immunoreactive. In the medial parvicellular subnucleus of the PVN, CART and FG coexisted with thyrotrophin-releasing hormone, whereas very few of the corticotrophin-releasing hormone containing cells were CART-immunoreactive. In the arcuate nucleus, CART was extensively colocalized with pro-opiomelanocortin in the ventrolateral part, but completely absent from neuroendocrine neurones of the dorsomedial part. To assess the possible role of CART as a hypothalamic-releasing factor, immunoreactive CART was measured in blood samples from the long portal vessels connecting the median eminence with the anterior pituitary gland. Adult male rats were anaesthetized and the infundibular stalk exposed via a transpharyngeal approach. The long portal vessels were transected and blood collected in 30-min periods (one prestimulatory and three poststimulatory periods). Compared to systemic venous plasma samples, baseline concentrations of immunoreactive CART were elevated in portal plasma. Exposure to sodium nitroprusside hypotension triggered a two-fold elevation of portal CART42-89 immunoreactivity throughout the 90-min stimulation period. In contrast, the concentration of portal plasma CART immunoreactivity dropped in the vehicle infused rats. The current study provides further evidence that CART is a neuroendocrine-releasing factor with a possible impact on anterior pituitary function during states of haemodynamic stress.
AB - Cocaine- and amphetamine-regulated transcript (CART) is present in a number of hypothalamic nuclei. Besides actions in circuits regulating feeding behaviour and stress responses, the hypothalamic functions of CART are largely unknown. We report that CART immunoreactivity is present in hypothalamic neuroendocrine neurones. Adult male rats received a systemic injection of the neuronal tracer Fluorogold (FG) 2 days before fixation, and subsequent double- and triple-labelling immunoflourescence analysis demonstrated that neuroendocrine CART-containing neurones were present in the anteroventral periventricular, supraoptic, paraventricular (PVN) and periventricular nuclei of the hypothalamus. In the PVN, CART-positive neuroendocrine neurones were found in all of cytoarchitectonically identified nuclei. In the periventricular nucleus, approximately one-third of somatostatin cells were also CART-immunoreactive. In the medial parvicellular subnucleus of the PVN, CART and FG coexisted with thyrotrophin-releasing hormone, whereas very few of the corticotrophin-releasing hormone containing cells were CART-immunoreactive. In the arcuate nucleus, CART was extensively colocalized with pro-opiomelanocortin in the ventrolateral part, but completely absent from neuroendocrine neurones of the dorsomedial part. To assess the possible role of CART as a hypothalamic-releasing factor, immunoreactive CART was measured in blood samples from the long portal vessels connecting the median eminence with the anterior pituitary gland. Adult male rats were anaesthetized and the infundibular stalk exposed via a transpharyngeal approach. The long portal vessels were transected and blood collected in 30-min periods (one prestimulatory and three poststimulatory periods). Compared to systemic venous plasma samples, baseline concentrations of immunoreactive CART were elevated in portal plasma. Exposure to sodium nitroprusside hypotension triggered a two-fold elevation of portal CART42-89 immunoreactivity throughout the 90-min stimulation period. In contrast, the concentration of portal plasma CART immunoreactivity dropped in the vehicle infused rats. The current study provides further evidence that CART is a neuroendocrine-releasing factor with a possible impact on anterior pituitary function during states of haemodynamic stress.
KW - Animals
KW - Common Variable Immunodeficiency
KW - Hypothalamo-Hypophyseal System
KW - Male
KW - Nerve Tissue Proteins
KW - Neural Pathways
KW - Neurons
KW - Neurotransmitter Agents
KW - Rats
KW - Rats, Wistar
KW - Stress, Physiological
U2 - 10.1046/j.1365-2826.2003.00960.x
DO - 10.1046/j.1365-2826.2003.00960.x
M3 - Journal article
C2 - 12588509
VL - 15
SP - 219
EP - 226
JO - Journal of Neuroendocrinology
JF - Journal of Neuroendocrinology
SN - 0953-8194
IS - 3
ER -
ID: 132056270