Figure 1. Mean arterial blood pressure (MABP) in conscious endothelial nitric oxide synthase (eNOS) mutant and wild-type mice. Blood pressure in the eNOS mutant animals was higher than that in their wild-type counterparts; this difference was more marked in male than in female animals. From Rees et al. (2000), with permission.

Figure 2. Effect of N^G-monomethyl-l-arginine (L-NMMA) on mean arterial pressure in a patient with septic shock. Arrows show bolus injections of L-NMMA (1, 0.3 mg kg^{– 1}; 2, 0.3 mg kg^{– 1}; 3, 1 mg kg^{– 1}). Hatching indicates noradrenaline infusions (g kg^{– 1} min^{– 1}), as shown. From Petros et al. (1991), with permission.

Figure 3. Immunohistochemical demonstration of nitrergic degeneration in the corpus cavernosum of streptozotocin-induced diabetic rats. Neuronal nitric oxide synthase (nNOS) immunostaining in (a) a control rat, (b) a 4-week diabetic rat (note the varicosity formation and breakage in the nerve fibres), (c) an 8-week diabetic rat (note that the nitrergic nerves have become very sparse), (d) an 8-week diabetic rat treated with the NOS inhibitor N^G-nitro-l-arginine methyl ester (L-NAME) (note that the structure and number of nitrergic nerve fibres are preserved during diabetes) and (e) a rat treated with L-NAME for 8 weeks (note that the structure and number of nerve fibres are not different from those in (a)). Bar, 33 m for (c), 43 m for others. The results are typical of those observed in 6–12 animals in each. From Cellek et al. (1999), with permission.

Figure 4. Nitrite concentration (determined by chemiluminescence) in synovial fluid (SF) and serum samples from patients with rheumatoid arthritis (RA) and osteoarthritis (OA), and in serum samples from controls matched for age and sex. From Farrell et al. (1992), with permission.