geoscience.net logo
+ Resolve Article
+ Follow Us
Follow on FacebookFollow on Facebook
Follow on TwitterFollow on Twitter

+ Translate
+ Subscribe to Site Feed
GeoScience Most Shared ContentMost Shared Content

Does nitric oxide contribute to the basal vasodilation of pregnancy in conscious rabbits?


, : Does nitric oxide contribute to the basal vasodilation of pregnancy in conscious rabbits?. American Journal of Physiology. Regulatory, Integrative and Comparative Physiology 281(5): R1624-R1632

Pregnancy produces marked systemic vasodilation, but the mechanism is unknown. Experiments were performed in conscious rabbits to test the hypotheses that increased nitric oxide (NO) production contributes to the increased vascular conductance, but that the contribution varies among vascular beds. Rabbits were instrumented with aortic and vena caval catheters and ultrasonic flow probes implanted around the ascending aorta, superior mesenteric artery, terminal aorta, and/or a femoral artery. Hemodynamic responses to intravenous injection of Nq-nitro-L-arginine (L-NA; 20 mg/kg or increasing doses of 2, 5, 10, 15, and 20 mg/kg) were determined in rabbits first before pregnancy (NP) and then at the end of gestation (P). L-NA produced similar increases in arterial pressure between groups, but the following responses were larger (P < 0.05) when the rabbits were pregnant: 1) decreases in total peripheral conductance [-3.7 [plus or minus] 0.3 (NP), -5.0 [plus or minus] 0.5 (P) ml min-1 mmHg-1], 2) decreases in mesenteric conductance [-0.47 [plus or minus] 0.05 (NP), -0.63 [plus or minus] 0.07 (P) ml min-1 mmHg-1], 3) decreases in terminal aortic conductance [-0.43 [plus or minus] 0.05 (NP), -0.95 [plus or minus] 0.19 ml min-1 mmHg-1 (P)], and 4) decreases in heart rate [-41 [plus or minus] 4 (NP), -62 [plus or minus] 5 beats/min (P)]. Nevertheless, total peripheral and terminal aortic conductances remained elevated in the pregnant rabbits (P < 0.05) after L-NA. Furthermore, decreases in cardiac output and femoral conductance were not different between the reproductive states. We conclude that the contribution of NO to vascular tone increases during pregnancy, but only in some vascular beds. Moreover, the data support a role for NO in the pregnancy-induced increase in basal heart rate. Finally, unknown factors in addition to NO must also underlie the basal vasodilation observed during pregnancy. Reprinted by permission of the publisher.

US$29.90

PMID: 11641135


Other references

Guo, Y.; Harwalkar, J.; Stacey, D.W.; Hitomi, M., 2004: Destabilization of cyclin D1 message plays a critical role in cell cycle exit upon mitogen withdrawal. Cyclin D1 is critical for entry into, continuation of, and exit from the cell division cycle. Mitogen stimulation of quiescent cells induces cyclin D1 expression in a transcription-dependent manner. In actively cycling cells, on the other hand, fl...

Pappu, B.P.; Angkasekwinai, P.; Dong, C., 2008: Regulatory mechanisms of helper T cell differentiation: new lessons learned from interleukin 17 family cytokines. Interleukin 17 (IL-17) family consists of six cytokines in mammals. Among them, IL-17 and IL-17F are expressed by a novel subset of CD4+ helper T (Th) cells and play critical function in inflammation and autoimmunity. On the other hand, IL-17E, al...

Kubasiewicz, L., 1984: Milk fat content in progeny of bulls - carriers of achondroplasia. Milk fat percentage was studied in 3623 daughters of 44 bulls that are carriers of the achondroplasia gene, and in 6982 daughters of non-carrier bulls. In the case of only 1 carrier bull was there a significant difference in fat percentage between...

Valenzuela, R.B., 1961: El chercen, Troglodytes musculus chilensis Lesson. Revista de la Universidad Catolica Santiago, 46: 45-53

Valencia, M.C.; Nicolas, E.A.; Capitan Vallvey, L.F., 1999: Speciation of selenium (IV) in natural waters by solid phase spectrophotometry. A method for the speciation of selenium (IV) based on solid-phase spectrophotometry (SPS), is described. In acidic conditions selenium (IV) oxidizes potassium iodide and the I3- forms an ionic association with Rhodamine B (RB) which is fixed on a...

de Vera Floristán, C.J.; Peña Porta, J.M.; Puig Giro, R.; Guajardo Guajardo, J., 2001: 74-year-old male with abdominal pain and hypotension. Revista Clinica Espanola 200(10): 573-574

Satou, R.; Miyanaga, A.; Ozawa, H.; Funa, N.; Katsuyama, Y.; Miyazono, K-ichi.; Tanokura, M.; Ohnishi, Y.; Horinouchi, S., 2014: Structural basis for cyclization specificity of two Azotobacter type III polyketide synthases: a single amino acid substitution reverses their cyclization specificity. Type III polyketide synthases (PKSs) show diverse cyclization specificity. We previously characterized two Azotobacter type III PKSs (ArsB and ArsC) with different cyclization specificity. ArsB and ArsC, which share a high sequence identity (71%),...

Caldicott, W.J.; Taub, K.J.; Hollenberg, N.K., 1977: Identical mesenteric, femoral and renal vascular responses to angiotensin II and III in the dog. Life Sciences 20(3): 517-521

Behmer, S.T.; Joern, A., 1994: The influence of proline on diet selection: sex-specific feeding preferences by the grasshoppers Ageneotettix deorum and Phoetaliotes nebrascensis (Orthoptera: Acrididae). The effect of proline as a feeding stimulant in reproductively-active grasshoppers was studied using the graminivorous Ageneotettix deorum and the generalist (but mostly graminivorous) Phoetaliotes nebrascensis. Females, but not males, of both spe...

Aidinis, V.; Carninci, P.; Armaka, M.; Witke, W.; Harokopos, V.; Pavelka, N.; Koczan, D.; Argyropoulos, C.; Thwin, M-Maung.; Möller, S.; Waki, K.; Kazunori, W.; Gopalakrishnakone, P.; Ricciardi-Castagnoli, P.; Thiesen, H-Jürgen.; Hayashizaki, Y.; Kollias, G., 2005: Cytoskeletal rearrangements in synovial fibroblasts as a novel pathophysiological determinant of modeled rheumatoid arthritis. Rheumatoid arthritis is a chronic inflammatory disease with a high prevalence and substantial socioeconomic burden. Despite intense research efforts, its aetiology and pathogenesis remain poorly understood. To identify novel genes and/or cellular...