Localization of neuropeptide Y and norepinephrine in the porcine ovarian artery and their influence on the local blood pressure.
The aim of the present study was to determine: (i) the presence of dopamine-beta-hydroxylase (DbetaH)- and neuropeptide Y (NPY)-immunoreactive (IR) nerve fibres in the wall of the porcine ovarian artery, (ii) the influence of NPY and norepinephrine (NE) on the contractile activity of the pig ovarian arteries, and (iii) the pharmacological analysis of the interaction between NPY and NE in the isolated porcine ovarian arteries collected from immature pigs and from animals in different days of the estrous cycle. Ovarian arteries for immunohistochemistry and isolated arteries for pharmacological studies were excised from immature pigs and mature animals on days 1-5, 8-13 and 17-20 of the estrous cycle. The study showed that both DbetaH- and NPY-IR nerve fibres were present in the pig ovarian arteries in all periods examined, and, that in some fibres DbetaH and NPY were co-localized. Both NE (10(-6) M) and NPY (10(-7) M) increased blood pressure of examined preparations, however, NE caused stronger changes in the vessel wall tension (P<0.001), than did NPY. NE significantly increased (P<0.001) blood pressure of all isolated arteries, however, this response was stronger in vessels from days 1-5 of the cycle, when compared to days 8-13 (P<0.01), 17-20 and immature pigs (P<0.001). NPY increased significantly blood pressure in isolated arteries from days 8-13 and 17-20 of the cycle (P<0.001), while in preparations taken from immature pigs and animals on days 1-5 of the estrous cycle this response was somewhat weaker (P<0.01). A higher elevation (P<0.001) of blood pressure after NPY administration was observed in isolated arteries from days 17-20 of the cycle, when compared to vessels from days 1-5 and 8-13 and those from immature pigs. Moreover, NE significantly intensified (P<0.001) an increase in the blood pressure in isolated arteries pre-treated with NPY in all periods examined. NPY insignificantly (P>0.05) potentiated increase of blood pressure in NE pre-treated vessels of immature pigs and in isolated arteries from days 17-20 of the cycle and significantly (P<0.05) in vessels from days 1-5 and 8-13 of the estrous cycle. Our results indicate that DbetaH- and NPY-IR nerve fibres are present in the pig ovarian arteries. NE and NPY administered alone increased blood pressure in the pig isolated ovarian artery and simultaneous administration of both substances caused each other potentiation of vasocontractile effect, however, the strength of observed changes was dependent on the stage of the estrous cycle.
Department of Pharmacology, Faculty of Veterinary Medicine, University of Warmia and Mazury, Olsztyn, Poland. mark@uwm.edu.pl
Włodzimierz
W
Markiewicz
Jerzy J
JJ
Jaroszewski
Beata
B
Barszczewska
Waldemar
W
Sienkiewicz
D000375:Aging / Q000502:physiology; D000818:Animals; D001158:Arteries / Q000187:drug effects / Q000294:innervation* / Q000502:physiology; D001794:Blood Pressure / Q000187:drug effects / Q000502:physiology; D004305:Dose-Response Relationship, Drug; D030762:Estrous Cycle / Q000502:physiology; D005260:Female; D007150:Immunohistochemistry; D009131:Muscle, Smooth, Vascular / Q000187:drug effects / Q000294:innervation / Q000502:physiology; D009478:Neuropeptide Y / Q000378:metabolism* / Q000494:pharmacology; D009638:Norepinephrine / Q000378:metabolism* / Q000494:pharmacology; D010053:Ovary / Q000098:blood supply* / Q000502:physiology; D012039:Regional Blood Flow / Q000187:drug effects / Q000502:physiology; D034421:Sus scrofa / Q000033:anatomy & histology / Q000378:metabolism*; D017779:Sympathetic Fibers, Postganglionic / Q000166:cytology / Q000378:metabolism*; D014661:Vasoconstriction / Q000187:drug effects / Q000502:physiology
D009478:Neuropeptide Y; D009638:Norepinephrine