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

BACKGROUND The present-day amphibian and reptile fauna of Western Siberia are the least diverse of the Palaearctic Realm, as a consequence of the unfavourable climatic conditions that predominate in this region. The origin and emergence of these herpetofaunal groups are poorly understood. Aside from the better-explored European Neogene localities yielding amphibian and reptile fossil remains, t...

In order to probe the organization of the contractile machinery in smooth muscle, we have studied the distribution of a-actinin, a protein present in high concentration in dense bodies, structures apparently analogous to the Z-disks of striated muscle. Localization of aactinin in single isolated smooth muscle cells ofthe stomach muscularis of Bufo marinus was determined by analysis of the patte...

Cardiac output and peripheral resistance have not been measured in conscious anuran amphibians, although some data exist for pithed and anaesthetized frogs (Shelton and Jones, 1965a,b; Shelton, 1970; Tazawa et al. 1979). The periodic lung ventilation characteristic of conscious anurans could increase cardiac output reflexively or by changes in venous return, as in mammals. Furthermore, because ...

Chronic obstructive pulmonary disease (COPD) is chronic inflammation leading to irreversible airway obstruction. Previous studies showed increased metalloproteinases (MMP) level, especially MMP-9, as a sign of local inflammation. Up-to-date, only a few studies estimated the MMP-9 serum concentration in COPD with respect to correlation with systemic inflammation. The aim of the present study was...

Cynthia A; HRANITZ, John M; Bloomsburg University; [email protected] Temperature-Induced Stress Responses in the Blackworm (Lumbriculus variegatus) The aquatic worm Lumbriculus variegatus (blackworm) is an ideal candidate for toxicity testing and is being used increasingly to assess ecological risk. Blackworms are sensitive to sublethal doses of various toxins and display readily observable b...