- Tytuł:
- Neuropeptide Y as a presynaptic modulator of norepinephrine release from the sympathetic nerve fibers in the pig pineal gland
- Autorzy:
-
Ziolkowska, N.
Lewczuk, B.
Przybylska-Gornowicz, B. - Powiązania:
- https://bibliotekanauki.pl/articles/30183.pdf
- Data publikacji:
- 2015
- Wydawca:
- Polska Akademia Nauk. Czytelnia Czasopism PAN
- Opis:
- Norepinephrine (NE) released from the sympathetic nerve endings is the main neurotransmitter controlling melatonin synthesis in the mammalian pineal gland. Although neuropeptide Y (NPY) co-exists with NE in the pineal sympathetic nerve fibers it also occurs in a population of non-adrenergic nerve fibers located in this gland. The role of NPY in pineal physiology is still enigmatic. The present study characterizes the effect of NPY on the depolarization-evoked 3H-NE release from the pig pineal explants. The explants of the pig pineal gland were loaded with 3H-NE in the presence of pargyline and superfused with Tyrode medium. They were exposed twice to the modified Tyrode medium containing 60 mM of K+ to evoke the 3H-NE release via depolarization. NPY, specific agonists of Y1- and Y2-receptors and pharmacologically active ligands of a2-adrenoceptors were added to the medium before and during the second depolarization. The radioactivity was measured in medium fractions collected every 2 minutes during the superfusion. NPY (0.1 - 10 μM) significantly decreased the depolarization-induced 3H-NE release. Similar effect was observed after the treatment with Y2-agonist: NPY13-36, but not with Y1-agonist: [Leu31,Pro34]-NPY. The tritium overflow was lower in the explants exposed to the 5 μM NPY and 1 μM rauwolscine than to rauwolscine only. The effects of 5 μM NPY and 0.05 μM UK 14,304 on the depolarization-evoked 3H-NE release were additive. The results show that NPY is involved in the regulation of NE release from the sympathetic terminals in the pig pineal gland, inhibiting this process via Y2-receptors.
- Źródło:
-
Polish Journal of Veterinary Sciences; 2015, 18, 1
1505-1773 - Pojawia się w:
- Polish Journal of Veterinary Sciences
- Dostawca treści:
- Biblioteka Nauki
Artykuł