777 SAFETY, TOLERABILITYAND PHARMACOKINETIC OF MULTIPLE ASCENDING DOSES OF THE EP-1 RECEPTOR ANTAGONIST ONO-8539, A POTENTIAL NEW AND NOVEL THERAPY TO OVERACTIVE BLADDER IN HEALTHY YOUNG AND ELDERLY SUBJECTS

This study examined auditory temporal sensitivity in young adult and elderly listeners using psychophysical tasks that measured duration discrimination. Listeners in the experiments were divided into groups of young and elderly subjects with normal hearing sensitivity and with mild-to-moderate sloping sensorineural hearing loss. Temporal thresholds in all tasks were measured with an adaptive forced-choice procedure using tonal stimuli centered at 500 Hz and 4000 Hz. Difference limens for duration were measured for tone bursts (250 msec reference duration) and for silent intervals between tone bursts (250 msec and 6.4 msec reference durations). Results showed that the elderly listeners exhibited diminished duration discrimination for both tones and silent intervals when the reference duration was 250 msec. Hearing loss did not affect these results. Discrimination of the brief temporal gap (6.4 msec) was influenced by age and hearing loss, but these effects were not consistent across all listeners. Effects of stimulus frequency were not evident for most of the duration discrimination conditions.

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A comparison of fasting serum amino acid profiles of young and elderly subjects.

Journal of the American College of Nutrition ◽

10.1080/07315724.1991.10718185 ◽

1991 ◽

Vol 10 (6) ◽

pp. 668-674 ◽

Cited By ~ 22

Author(s):

G Sarwar ◽

H G Botting ◽

M Collins

Keyword(s):

Amino Acid ◽

Elderly Subjects ◽

Fasting Serum ◽

Amino Acid Profiles ◽

Young And Elderly Subjects

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Atrial natriuretic peptide suppresses osmostimulated vasopressin release in young and elderly humans

AJP Endocrinology and Metabolism ◽

10.1152/ajpendo.1991.261.2.e252 ◽

1991 ◽

Vol 261 (2) ◽

pp. E252-E256 ◽

Cited By ~ 1

Author(s):

B. A. Clark ◽

D. Elahi ◽

L. Fish ◽

M. McAloon-Dyke ◽

K. Davis ◽

...

Keyword(s):

Atrial Natriuretic Peptide ◽

Hypertonic Saline ◽

Natriuretic Peptide ◽

Serum Sodium ◽

The Elderly ◽

Sodium Concentration ◽

Elderly Subjects ◽

Vasopressin Release ◽

Young And Elderly Subjects ◽

Atrial Natriuretic

Atrial natriuretic peptide (ANP) may suppress vasopressin release, but the dynamics of this interaction as well as the influence of age have not been defined. We studied six or seven young (19-40 yr old) and seven elderly volunteers (65-83 yr old) under two circumstances: 1) after infusion of 5% saline (0.04 ml.kg-1.min-1) for 2 h and 2) after the same infusion given with simultaneous synthetic human ANP (0.05 micrograms.kg-1.min-1). Hypertonic saline alone produced a progressive rise in plasma vasopressin with increasing serum sodium. During hypertonic saline alone, vasopressin levels began to rise at an increment in serum sodium of 1.67 +/- 0.35 mM in the young and 1.43 +/- 0.32 mM in the elderly and rose linearly with increasing serum sodium. When ANP was infused with hypertonic saline (with peak ANP levels of approximately 1,000 pM), vasopressin levels began to rise at an increment in serum sodium of 4.43 +/- 0.67 mM in the young and 4.57 +/- 0.43 mM in the elderly (P less than 0.01 vs. saline alone). Furthermore, the vasopressin response for any given serum sodium was significantly reduced in both young and elderly subjects, resulting in a rightward displacement of the curve relating vasopressin response to sodium concentration (P less than 0.001). In conclusion, ANP not only suppresses vasopressin but raises the threshold for release of vasopressin in response to osmotic stimulation in both young and elderly individuals. High circulating ANP levels may be responsible in part for the suppression of vasopressin levels and water diuresis seen during states of volume expansion.

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