In:
American Journal of Physiology-Regulatory, Integrative and Comparative Physiology, American Physiological Society, Vol. 299, No. 3 ( 2010-09), p. R960-R967
Abstract:
Postprandial hypotension occurs frequently and is associated with increased morbidity. Gastric distension may attenuate the postprandial fall in blood pressure (BP). Using a barostat, we sought to determine the effects of gastric distension on BP, heart rate (HR), and superior mesenteric artery (SMA) blood flow responses to intraduodenal glucose in eight (6 men, 2 women) healthy older (65–75 yr old) subjects. BP and HR were measured using an automated device and SMA blood flow was measured using Doppler ultrasound on 4 days in random order. SMA blood flow was calculated using the radius of the SMA and time-averaged mean velocity. Subjects were intubated with a nasoduodenal catheter incorporating a duodenal infusion port. On 2 of the 4 days, they were intubated orally with a second catheter, incorporating a barostat bag, positioned in the fundus and set at 8 mmHg above minimal distending pressure. Each subject received a 60-min (0–60 min) intraduodenal infusion of glucose (3 kcal/min) or saline (0.9%); therefore, the four study conditions were as follows: intraduodenal glucose + barostat (glucose + distension), intraduodenal saline + barostat (saline + distension), intraduodenal glucose (glucose), and intraduodenal saline (saline). Systolic and diastolic BP fell during glucose compared with saline ( P = 0.05 and P = 0.003, respectively) and glucose + distension ( P = 0.01 and P = 0.05, respectively) and increased during saline + distension compared with saline ( P = 0.04 and P = 0.006, respectively). The maximum changes in systolic BP were −14 ± 5, +11 ± 2, −3 ± 4, and +15 ± 3 mmHg for glucose, saline, glucose + distension, and saline + distension, respectively. There was an increase in HR during glucose and glucose + distension (maximum rise = 14 ± 2 and 14 ± 3 beats/min, respectively), but not during saline or saline + distension. SMA blood flow increased during glucose and glucose + distension (2,388 ± 365 and 1,673 ± 187 ml/min, respectively), but not during saline, and tended to decrease during saline + distension (821 ± 115 and 864 ± 116 ml/min, respectively). In conclusion, gastric distension has the capacity to abolish the fall in BP and attenuate the rise in SMA blood flow induced by intraduodenal glucose in healthy older subjects.
Type of Medium:
Online Resource
ISSN:
0363-6119
,
1522-1490
DOI:
10.1152/ajpregu.00235.2010
Language:
English
Publisher:
American Physiological Society
Publication Date:
2010
detail.hit.zdb_id:
1477297-8
SSG:
12
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