Cervical stimulation activates A1 and locus coeruleus neurons that project to the paraventricular nucleus of the hypothalamus
Autor: | Richard Bertram, Raphael E. Szawka, De’Nise T. McKee, C. V. V. Helena, Marc E. Freeman, Maristela O. Poletini |
---|---|
Rok vydání: | 2012 |
Předmět: |
medicine.medical_specialty
endocrine system Hypothalamo-Hypophyseal System Stilbamidines Tyrosine 3-Monooxygenase Lactotrophs Ovariectomy Lumbosacral Plexus Stimulation Nerve Tissue Proteins Cervix Uteri Biology Oxytocin Axonal Transport Article Rats Sprague-Dawley Dopamine Internal medicine Copulation Neural Pathways medicine Animals Fluorescent Dyes Neurons Medulla Oblongata Tyrosine hydroxylase General Neuroscience Prolactin Circadian Rhythm Rats Endocrinology medicine.anatomical_structure nervous system Hypothalamus Locus coeruleus Female Locus Coeruleus Nucleus Proto-Oncogene Proteins c-fos hormones hormone substitutes and hormone antagonists medicine.drug Paraventricular Hypothalamic Nucleus |
Zdroj: | Brain research bulletin. 88(6) |
ISSN: | 1873-2747 |
Popis: | In female rats, stimulation of the uterine cervix during mating induces two daily surges of prolactin. Inhibition of hypothalamic dopamine release and stimulation of oxytocin neurons in the paraventricular nucleus (PVN) are required for prolactin secretion. We aim to better understand how stimulation of the uterine cervix is translated into two daily prolactin surges. We hypothesize that noradrenergic neurons in the A1, A2, and locus coeruleus (LC) are responsible for conveying the peripheral stimulus to the PVN. In order to determine whether projections from these neurons to the PVN are activated by cervical stimulation (CS), we injected a retrograde tracer, Fluoro-Gold (FG), into the PVN of ovariectomized rats. Fourteen days after injection, animals were submitted to artificial CS or handling and perfused with a fixative solution. Brains were removed and sectioned from the A1, A2, and LC for c-Fos, tyrosine hydroxylase (TH), and FG triple-labeling using immunohistochemistry. CS increased the percentage of TH/FG+ double-labeled neurons expressing c-Fos in the A1 and LC. CS also increased the percentage of TH+ neurons expressing c-Fos within the A1 and A2, independent of their projections to the PVN. Our data reinforce the significant contributions of the A1 and A2 to carry sensory information during mating, and provide evidence of a functional pathway in which CS activates A1 and LC neurons projecting to the PVN, which is potentially involved in the translation of CS into two daily prolactin surges. |
Databáze: | OpenAIRE |
Externí odkaz: |