Biomedical subjects

N C Wynn

Publications and source records attributed to N C Wynn.

3 recordsLinked to original sources

PubMed1985

Renal functional status and patterns of catecholamine excretion.

Twenty-four hour urinary catecholamine measurements were obtained in seven normal individuals and 23 patients with essential hypertension or renal disease. As renal function decreased, large reductions in the excretion of free catecholamines and total dopamine were measured. Since urinary catecholamine measurements are used for diagnostic and physiologic studies, our data indicate a need to assess renal function for accurate interpretation of these measurements. Our results are also consistent with a renal origin for a major portion of the urinary dopamine content.

Adult↗

PubMedDate not supplied

MacCueSee: a quality control program for the Macintosh computer.

MacCueSee was written to perform routine calculations on quality control concentration values from radioimmunoassay. It is written in Microsoft QuickBASIC for the Apple Macintosh computer. The program calculates within and between assay standard deviation (S.D.) and coefficient of variation from a spreadsheet file containing concentration values of controls analyzed. It also calculates the average concentration +/- 1 S.D. and contraction +/- 2 S.D. to establish between assay ranges. Its flexibility permits varying replicates between assays and automatic exclusion of missed assays. Within assay variability calculations are made for single, duplicate, and triplicate tubes. Results are displayed and can optionally be printed. In addition to radioimmunoassay, MacCueSee can be applied to a number of analytical methods in which quality control is monitored. An example of program use is included.

Microcomputers↗

PubMedDate not supplied

Dopamine and L-dopa potentiation of pressor responses to norepinephrine in isolated perfused rat kidneys.

The ability of l-dopa and dopamine to modulate renal vascular responses to norepinephrine (NE, 50-150 ng) was examined in isolated Tyrode-perfused kidneys from male Sprague-Dawley rats. Renal pressor responses to bolus injections of NE were constant during saline infusion. In contrast, l-dopa (15 micrograms/min and 75 micrograms/min) and dopamine (15 micrograms/min) infusions that did not alter baseline perfusion pressure increased pressor responses to NE significantly. Concomitant infusion of the aromatic l-amino-acid decarboxylase inhibitor carbidopa (20 micrograms/min) suppressed the ability of l-dopa (75 micrograms/min) but not dopamine to enhance renal pressor responses to NE. The pressor potentiation of NE did not appear to be the result of a general musculotropic effect or altered alpha-1 adrenoreceptor activity since increased vasoconstrictor responses to phenylephrine (PE) and serotonin (5-HT) were not observed. Infusions of cocaine (15 micrograms/min) enhanced the renal pressor effects of NE but not PE in similar fashion to l-dopa and dopamine. In the presence of cocaine, l-dopa did not potentiate NE constriction further. These results suggest that endogenous or exogenous dopamine in the kidney may affect neuronal NE uptake to enhance its renal vascular effects.

Animals↗