Arginine vasopressin (AVP), synthesized in hypothalamic neurons, is transported in axons either to the pituitary for release into the circulation or to different brain areas. In our previous experiments we documented central antipyretic AVP pathways from the hypothalamus to the ventrolateral septal area in the limbic system. In the present study we investigated if osmotic [...]
Total body water was determined on 59 boys and 59 girls and on 40 boys and 45 girls attending junior and senior high schools, respectively. The volunteers were studied for three years. They were given D2O (99.8%) orally, and urine samples were used for determination of the ratio of heavy hydrogen to normal hydrogen by [...]
Effects of water temperature and flavoring on fluid consumption and body weight losses were studied in fourteen unacclimatized men (21-33 years) during 6 hr of treadmill exercise (4.8 km.hr-1, 5% grade for 30 min.hr-1) in a hot environment. Subjects consumed each of four beverages (15 degrees C water, 40 degrees C water, 15 degrees C [...]
Alterations in urine concentrating ability with age were examined in 98 active community-dwelling volunteers (aged 20-79 years) who were free from evidence of diseases known to adversely affect renal function. There was a significant decrease in urine osmolality reached after 12 h dehydration with advancing age, which could not be correlated with the age-related decline [...]
This study was performed to determine whether a) children voluntarily dehydrate while exercising in hot climate; b) such dehydration affects their well-being and thermoregulation. Eleven 10p to 12-yr old, partially acclimatized boys underwent two work-in-the-heat protocols (cycle rides, 45% aerobic capacity at 39 degrees C, 45% rh). During one session they drank only voluntarily when [...]
The validity of the deuterium dilution technique as a method of measuring fluid intake was investigated by comparing values obtained with this technique and direct measurements of milk intake in 10 exclusively bottle-fed infants recovering from protein-energy malnutrition. Values for total body water were derived from body weight and length using Friis-Hansen's formula. During a [...]
Osmoreceptor sensitivity, as estimated by the plasma vasopressin (AVP) response to hypertonic saline infusion, increases with age. We studied volume-pressure sensitivity, as estimated by the plasma AVP response to orthostasis, in healthy young (19-31 yr old; n = 12) and old (62-80 yr old; n = 15) subjects. After remaining recumbent overnight (minimum of 8 [...]
No abstract available.
No abstract available.
A prospective study was undertaken to investigate the incidence and aetiology of acute confusional states in physically ill old people. The subjects were 71 patients aged 70 years or over who were admitted as emergencies to a general medical unit. Mental testing revealed that: (a) one in six patients had an acute confusional state on [...]