The Spatial Relationship of γ-Aminobutyric Acid (GABA) Neurons and Gonadotropin-Releasing Hormone (GnRH) Neurons in Larval and Adult Sea Lamprey, Petromyzon marinus

2002 ◽  
Vol 60 (1) ◽  
pp. 1-12 ◽  
Author(s):  
Karen L. Reed ◽  
Janet K. MacIntyre ◽  
Stuart A. Tobet ◽  
Vance L. Trudeau ◽  
Lisa MacEachern ◽  
...  
Keyword(s):  
Petromyzon Marinus ◽  
Spatial Relationship ◽  
Sea Lamprey ◽  
Gonadotropin Releasing Hormone ◽  
Aminobutyric Acid ◽  
Releasing Hormone ◽  
Gaba Neurons ◽  
Gnrh Neurons ◽  
Relationship Of

Neuroanatomical Relationship of Neuronal Nitric Oxide Synthase to Gonadotropin-Releasing Hormone and Kisspeptin Neurons in Adult Female Sheep and Primates

2018 ◽  
Vol 107 (3) ◽  
pp. 218-227 ◽  
Author(s):  
Michelle N. Bedenbaugh ◽  
Richard B. McCosh ◽  
Justin A. Lopez ◽  
John M. Connors ◽  
Robert L. Goodman ◽  
...  
Keyword(s):  
Nitric Oxide ◽  
Adult Female ◽  
Gonadotropin Releasing Hormone ◽  
Releasing Hormone ◽  
Gnrh Neurons ◽  
Oxide Synthase ◽  
Relationship Of ◽  
Female Sheep ◽  
Dual Label ◽  
Close Contacts

Background: Neuronal intermediates that communicate estrogen and progesterone feedback to gonadotropin-releasing hormone (GnRH) neurons are essential for modulating reproductive cyclicity. Individually, kisspeptin and nitric oxide (NO) influence GnRH secretion. However, it is possible these 2 neuronal intermediates interact with one another to affect reproductive cyclicity. Methods: We investigated the neuroanatomical relationship of one isoform of the enzyme that synthesizes NO, neuronal NO synthase (nNOS), to kisspeptin and GnRH in adult female rhesus monkeys and sheep using dual-label immunofluorescence. Additionally, we evaluated if the phase of the reproductive cycle would affect these relationships. Results: Overall, no effect of the stage of cycle was observed for any variable in this study. In the arcuate nucleus (ARC) of sheep, 98.8 ± 3.5% of kisspeptin neurons colocalized with nNOS, and kisspeptin close-contacts were observed onto nNOS neurons. In contrast to ewes, no colocalization was observed between kisspeptin and nNOS in the infundibular ARC of primates, but kisspeptin fibers were apposed to nNOS neurons. In the preoptic area of ewes, 15.0 ± 4.2% of GnRH neurons colocalized with nNOS. In primates, 38.8 ± 10.1% of GnRH neurons in the mediobasal hypothalamus colocalized with nNOS, and GnRH close-contacts were observed onto nNOS neurons in both sheep and primates. Conclusion: Although species differences were observed, this work establishes a neuroanatomical framework between nNOS and kisspeptin and nNOS and GnRH in adult female nonhuman primates and sheep.

Distribution of lamprey gonadotropin-releasing hormone in the brain and pituitary gland of larval, metamorphic, and adult sea lampreys, Petromyzon marinus

1994 ◽  
Vol 72 (1) ◽  
pp. 48-53 ◽  
Author(s):  
Glenda M. Wright ◽  
Kim M. McBurney ◽  
John H. Youson ◽  
Stacia A. Sower
Keyword(s):  
Pituitary Gland ◽  
Preoptic Area ◽  
Petromyzon Marinus ◽  
Gonadotropin Releasing Hormone ◽  
Immunoperoxidase Technique ◽  
Dorsal Region ◽  
Releasing Hormone ◽  
Sea Lampreys ◽  
The Brain

Lamprey gonadotropin-releasing hormone was demonstrated in the brains of larval, metamorphic, and adult sea lampreys, Petromyzon marinus, using an immunoperoxidase technique. Gonadotropin-releasing hormone was observed in the neurohypophysis and preoptic area of the brain of larval, metamorphic, juvenile, and prespawning adults. The occurrence of immunoreactive cells and the intensity of the immunostaining was lowest in larvae, but by stage 5 of metamorphosis there was a marked increase in the prevalence and staining of these cells, which continued into adults. In larvae and lampreys in metamorphic stages 1–4, most immunoreactive fibres were confined to the dorsal region of the neurohypophysis. During stage 5 there was an expansion of immunopositive fibres into the ventral portion of the neurohypophysis. Prominent immunoreactivity was observed throughout the neurohypophysis from stage 5 onward through the adult stages. Changes in immunoreactivity of these cells and fibres in the brain and neurohypophysis correlate well with increased concentrations of hormone in the brain during development and with the timing of presumed changes in activity of cells in the adenohypophysis during metamorphosis.

Sign in / Sign up

Export Citation Format

Share Document