Search PubMed⌕ Search

Biomedical subjects

M Ganguli

Publications and source records attributed to M Ganguli.

85 records · Page 5Linked to original sources
PubMed1976

Low renal papillary plasma flow in both Dahl and Kyoto rats with spontaneous hypertension.

Abnormally low plasma flow to renal papilla characterizes Dahl hypertension. When eating a normal Na diet (0.3% NaCl) both hypertension-sensitive (S) rats and hypertension-resistant (R) rats, 16 weeks old, have fairly normal blood pressure (BP), averaging 144 and 129 mm Hg, respectively. However, even in this barely hypertensive state, 18 S rats had a 31% lower papillary plasma flow (Lilienfield method) than 22 R rats, 19.2 ml/100 g of papilla per min compared to 25.6 (P less than 0.001). When a high (8%) NaCl diet was fed for 7 days, R rats increased papillary plasma flow from 25.6 on 0.3% NaCl to 33.8 on 8% NaCl, a 32% rise (P less than 0.001). S rats increased papillary flow from 20.4 to 24.8, a 22% rise (P less than 0.05). When a high (8%) NaCl diet was fed for 4 weeks, R rats increased papillary plasma flow from 25.7 ml/100 g per min on 0.3% NaCl to 29.5 ml/100 g per min on 8% NaCl, a 15% rise (P less than 0.025). S rats increased papillary flow from 17.7 to 20.0 ml/100 g per min (not significant). S rats on 8% NaCl had a papillary flow 32% lower than R rats on 8% NaCl (P less than 0.001). BP of S rats rose to 162 mm Hg after 4 weeks on 8% NaCl; in R rats, BP did not rise at all. S rats on 0.3% NaCl have a low papillary flow even in a borderline hypertensive state. When challenged with 8% NaCl, R rats increased papillary flow, an adaptation possibly important for the natriuresis. S rats failed to achieve this same high papillary flow. Lacking this adaptation, hypertension may then conceivably occur in S rats to accomplish natriuresis through a "pressure natriuresis" mechanism. Papillary flow also decreased by 11% in 26 Kyoto 17-week-old spontaneously hypertensives (BP, 182 mm Hg) compared to 24 Kyoto normotensives (BP, 118 mm Hg), 29.5 vs 33.2 ml/100 g per min (P less than 0.001). Thus, low papillary flow exists in both hypertensions.

Animals↗
PubMedDate not supplied

Relationships between cerebrovascular events, APOE polymorphism and Alzheimer's disease in a community sample.

To investigate whether the APOE*4 allele modified the relationship between cerebrovascular events and Alzheimer's disease (AD), we collected evidence of previous stroke or transient ischemic attack (TIA) and determined APOE genotype among 102 subjects with AD and 375 nondemented subjects in a community-based study of dementia. Subjects with a history of stroke or TIA were twice as likely to have AD as subjects without such a history. However, APOE*4 carriers with a history of stroke/TIA were 5 times more likely than APOE*4 carriers without such a history to have AD (odds ratio = 5.3, 95% confidence interval = 1.4-20.9). History of stroke/TIA had little effect on the likelihood of having AD in subjects without an APOE*4 allele.

Aged↗
PubMedDate not supplied

Cognitive stability over 2 years in a rural elderly population: the MoVIES project.

In an ongoing prospective community study, a random sample of rural elderly persons was screened with cognitive tests (including the CERAD neuropsychological battery) at study entry and an average of 2 years later. We examined 1,017 subjects, nondemented at study entry, at both waves, with the Mini-Mental State Exam, Story Recall, Word List Recall and Recognition, Boston Naming Test, Verbal Fluency, Praxis, Clock Drawing, and Trailmaking. Overall, the cognitive performance was stable, with either no mean change or a small mean decline over 2 years; however, standard deviations were relatively large, implying individual variation of questionable clinical significance. These data provide a set of population-based longitudinal cognitive norms and have implications for dementia screening.

Aged↗
PubMedDate not supplied

Cardiac output and peripheral resistance in strains of rats sensitive and resistant to NaCl hypertension.

The interrelationship of blood pressure, cardiac output, and peripheral resistance was studied in Dahl "S" and "R" rats after 3 days on a high (8%) NaCl diet. Both "S" and "R" rats were normotensive when fed a normal (0.3%) NaCl diet. After 3 days of the high NaCl diet, the "R" rats remained normotensive (BP 112 mm Hg), while the "S" rats had an elevation of arterial pressure (BP 133 mm Hg) (p less than 0.001). The cardiac outputs of both "S" and "R" rats were similar on the low NaCl diet. After 3 days of high NaCl feeding, the cardiac output of the "R" rats rose 18% above the "R" control level (p less than 0.0001), while the peripheral resistance declined 14% below the "R" control level (p less than 0.005), and the blood pressure (BP) did not change, a pattern quite contrary to the concept of "whole-body" autoregulation. With a similar 3-day high NaCl feeding in "S" rats, cardiac output (p less than 0.005) and peripheral resistance (p less than 0.05) both increased 10%, while BP rose 20%. After 7 days of high NaCl feeding, the cardiac output of the "S" rats had returned to normal, while blood pressure and peripheral resistance both continued to be elevated. This pattern of response in "S" rats could be compatible with the concept of "whole-body" autoregulation. However, since both NaCl hypertension and Goldblatt hypertension can occur in settings in which "whole-body" autoregulation appears not be to causally related, one cannot be certain whether "whole-body" autoregulation is playing a causal role in the mechanism of NaCl-induced hypertension in "S" rats. It is a striking dichotomy that 3 days of high salt feeding produces vasoconstriction in "S" rats and vasodilation in "R" rats.

Animals↗
PubMedDate not supplied

Dahl S rats have increased natriuretic factor in atria but are markedly hyporesponsive to it.

Three experiments were carried out to determine whether atrial natriuretic factor (ANF) plays a part in Dahl hypertension. Results showed that ANF from both atria from 13 Dahl salt-sensitive (S) rats that had been fed a 4% NaCl diet for 12 weeks induced an average peak Na excretion of 23.0 muEq/min/g kidney in 13 Sprague-Dawley (SD) recipients vs 12.6 from atria from 13 salt-resistant (R) rats fed 4% NaCl (-45%, p less than 0.01), possibly indicating greater ANF secretion in S rats in order to enhance a reduced Na excretion. In 13 R rats, the ANF content in both atria increased from 14.0 after a 0.11% NaCl diet to 23.7 after 5 days of 4% NaCl diet (p less than 0.001) and then back to 12.6 after 12 weeks of 4% NaCl (p less than 0.001). Thus, ANF almost doubled after brief Na loading but returned to normal during continued Na loading. In S rats with a tendency to Na retention, ANF was elevated to about 23 in all three periods. ANF produced a 130-fold increase in natriuresis and a renal papillary plasma flow ( RPPF ) of 30.8 ml/min/100 g, 41% above the control level of 21.7, p less than 0.001. The marked increase in RPPF is very likely a partial cause of the natriuresis. A constant amount of ANF was continuously infused intravenously into 10 S rats and nine R rats all on 0.11% NaCl diets. Mean Na excretions in R and S were 5.3 and 4.6 muEq/min/100 g kidney before ANF.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMedDate not supplied

Serial sevens versus world backwards: a comparison of the two measures of attention from the MMSE.

This paper reports on a comparison of the two alternative tests of attention in the Mini-Mental State Examination (MMSE), a well-known cognitive screening tool. The two tests, serial subtraction by seven and backwards spelling of the word world, are often used interchangeably. In a large population-based sample, the two tests were found to be weakly associated with each other, with the former test appearing more difficult, although both were strongly associated with educational level. The authors discuss the implications of this finding in clinical and research settings, and make recommendations for more consistent use of the instrument.

Aged↗