Chemical modification of the backbone at the cleavage site in the (6-13)-octapeptide of equine angiotensinogen resulted in greatly increased binding affinity and resistance to cleavage by renin. The D-His6-Tyr13 octapeptide analog containing the reduced bond -CH2-NH-instead of a peptide bond -CO-NH- at the Leu10-Leu11 linkage (H-77) was a powerful in vitro inhibitor of canine renin (IC50 = 24nM). It gave an IC50 of 1 microM against human renin and 0.6 microM against rat renin. In sodium-depleted conscious dogs, infusion of H-77 caused dose-related falls of plasma angiotensin I plasma angiotensin II concentration and mean arterial pressure; the minimum effective dose was 0.1 mg . kg-1 hr-1. Similar infusions of H-77 in chronically catheterized rats have no effect on blood pressure or plasma angiotensin II concentration. Thus, the in vitro effect of H-77 as an inhibitor of renin in dog, human, and rat plasma was paralleled by its action in the whole animal.

Angiotensin I↗

PubMedDate not supplied

Key issues in the introduction of nurse endoscopy.

The inspection technique of gastrointestinal endoscopy is becoming increasingly popular and services in this area are expanding. Conditions which could only be treated by surgery can now be done endoscopically and this requires suitably trained medical staff. Consequently, there are demands from the medical and nursing professions to develop the role of the nurse endoscopist. This paper raises issues of concern to nurses who wish to undertake diagnostic endoscopy and suggests how the necessary skills and knowledge to gain competence can be obtained.

Education, Nursing, Continuing↗

PubMedDate not supplied

New pharmacologic approaches to acute spinal cord injury.

The incidence of spinal cord injury (SCI) in the United States is approximately 10,000 new cases per year. Strategies to prevent injury or salvage a few dermatomal levels may have significant effects on outcome. Several pharmacologic agents have been evaluated for their efficacy in patients with acute SCI. Methylprednisolone, when administered early, was the first drug to show significant improvement in outcome and is a standard of comparison for future agents. Several new drugs show promising results in animal models of SCI, with more extensive human trials currently under way. Results of more well-controlled clinical trials are necessary to determine which agents have significant neurologic benefits.

Antioxidants↗

PubMedDate not supplied

New pharmacologic strategies for acute neuronal injury.

The number of new drugs for treating neurotrauma is rapidly expanding. Emerging theories regarding the mechanisms of secondary neuronal injury provide the scientific basis for evaluating these new agents. Some of the most promising mechanisms for intervention are ionotropic channel antagonism, inhibition of lipid peroxidation, and neurotrophic factor augmentation. Many of these new agents are undergoing clinical trials to establish their roles in therapy.

Brain Injuries↗