In this study, the role of nitric oxide (NO) in regulation of the pulmocutaneous vasculature of the toad, Bufo marinus was investigated. In vitro myography demonstrated the presence of a neural NO signaling mechanism in both arteries. Vasodilation induced by nicotine was inhibited by the soluble guanylyl cyclase (GC) inhibitor, 1H-(1,2,4)oxadiazolo(4,3-a)quinoxalin-1-one, and the NO synthase (N...

This study determined the role of nitric oxide (NO) in neurogenic vasodilation in mesenteric resistance arteries of the toad Bufo marinus. NO synthase (NOS) was anatomically demonstrated in perivascular nerves, but not in the endothelium. ACh and nicotine caused TTX-sensitive neurogenic vasodilation of mesenteric arteries. The ACh-induced vasodilation was endothelium-independent and was mediate...

iii ACKNOWLEDGEMENTS I wish to thank my advisor Dr. Timothy Duong for supervision and guidance of my graduate studies and research; my thesis committee members Drs. Pardue for their time and suggestions with my proposal and defense. In addition I would like to thank Xiaoping Hu for financial support through his institutional training grant, Machelle Pardue for her advisement on fellowship propo...

Declining wetland areas cause many amphibian species to breed inside stormwater ponds (SWPs), which have been constructed alongside major roads collect and retain polluted road runoff water. However, the suitability of such artificial as a breeding habitat for amphibians remains unclear. Recently, study found very low survival rate European green toad tadpoles (Bufotes viridis) SWPs, presumably...

•The breeding habits of Bufo coccifer were studied in northwestern Costa Rica between 1971 and 1974. This species breeds during the rainy season, at least from May through August. Males chorus from areas of shallow water. Their calls resemble those of Mexican representatives of the species in pulse rate and duration, but are closer to those of other Costa Rican and Panamanian populations in dom...

In anuran amphibians, vascular filtrate and water of external origin enter the extensive subcutaneous spaces (Carter, 1979), which act as lymph reservoirs (Kampmeier, 1969). Although the volume of the lymphatic system is unknown, Thorson (1964) estimated 20 % of the total body weight of Bufo marinus (L.) to be occupied by interstitial fluid, including lymph. This will, of course, vary with the ...

Retrograde signaling from skeletal muscle cells to motor nerve terminals is a recognized mechanism for modulating the strength of neuromuscular transmission. We recently described a form of long-term depression of transmitter release at the mature neuromuscular junction that is dependent on the production of nitric oxide, most likely by the muscle cell (Etherington and Everett 2004 J Physiol (L...