Acute and chronic effects of SGLT2 blockade on glomerular and tubular function in the early diabetic rat

Tubuloglomerular feedback (TGF) stabilizes nephron function from minute to minute and adapts to different steady-state inputs to maintain this capability. Such adaptation inherently renders TGF less efficient at buffering long-term disturbances, but the magnitude of loss is unknown. We undertook the present study to measure the compromise between TGF and TGF adaptation in transition from acute to chronic decline in proximal reabsorption (Jprox). As a tool, we blocked proximal tubule sodium-glucose cotransport with the SGLT2 blocker dapagliflozin in hyperglycemic rats with early streptozotocin diabetes, a condition in which a large fraction of proximal fluid reabsorption owes to SGLT2. Dapagliflozin acutely reduced proximal reabsorption leading to a 70% increase in early distal chloride, a saturated TGF response, and a major reduction in single nephron glomerular filtration rate (SNGFR). Acute and chronic effects on Jprox were indistinguishable. Adaptations to 10–12 days of dapagiflozin included increased reabsorption by Henle's loop, which caused a partial relaxation in the increased tone exerted by TGF that could be explained without desensitization of TGF. In summary, TGF contributes to long-term fluid and salt balance by mediating a persistent decline in SNGFR as the kidney adapts to a sustained decrease in Jprox.

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Acute, medium and long-term effects of yellow sand and air pollutants on allergy and biomarker search

Impact ◽

10.21820/23987073.2020.3.63 ◽

2020 ◽

Vol 2020 (3) ◽

pp. 63-65

Author(s):

Tomomi Higashi

Keyword(s):

Air Pollutants ◽

Genetic Factors ◽

Long Term Effects ◽

Emergency Rooms ◽

Improve Treatment ◽

Treatment And Prevention ◽

Chronic Effects ◽

Difficulty Breathing ◽

Acute And Chronic Effects

Talk to any allergy sufferer and they will tell you how awful it can be. Runny noses, itchy eyes, coughing and difficulties breathing. For many these symptoms rise only to the level of annoyance and can be avoided by steering clear of the source of their allergy. What many people don't realise though is that allergies can become a far more serious issue for a large segment of the population. Shortness of breath and difficulty breathing due to allergies bring many people to emergency rooms and these are just the acute symptoms. Along with the potential for an allergic attack during a windy or dusty day, researchers and medical professionals are beginning to recognise that there are chronic, long term effects associated with allergies. In order to mitigate both the acute and chronic effects of allergies a better understanding of how genetic factors combine with environmental conditions to produce the ranges of symptoms and effects of allergy suffers is needed. Professor Tomomi Higashi, from the Department of Hygiene at Kanazawa University in Japan, is an expert in this field and is currently working to improve treatment and prevention of allergic disease.

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Volatile Substance Abuse: A Review of Possible Long-Term Neurological, Intellectual and Psychiatric Sequelae

The British Journal of Psychiatry ◽

10.1192/bjp.148.3.235 ◽

1986 ◽

Vol 148 (3) ◽

pp. 235-246 ◽

Cited By ~ 75

Author(s):

Maria A. Ron

Keyword(s):

Present Knowledge ◽

Long Term Effects ◽

Chronic Effects ◽

Structural Brain Damage ◽

Psychiatric Sequelae ◽

Volatile Substance Abuse ◽

Psychiatric Manifestations ◽

Acute And Chronic Effects

The possibility that chronic abuse of volatile substances can cause permanent neurological, psychiatric, and intellectual sequelae is critically reviewed. Toluene, present in the commonly used adhesives, is most often implicated in ‘glue sniffing’; this review focuses on its potential long-term effects. Many criticisms—particularly poor matching of control samples and inability to distinguish between acute and chronic effects—can be levelled at the available studies, while no adequate follow-up studies have been performed. In the light of present knowledge, the possibility that permanent structural brain damage, with accompanying psychiatric manifestations, results from solvent abuse remains inconclusive.

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Acute and chronic effects of octreotide on thyroid axis in growth hormone-secreting and clinically non-functioning pituitary adenomas

Acta Endocrinologica ◽

10.1530/eje.0.1330189 ◽

1995 ◽

Vol 133 (2) ◽

pp. 189-194 ◽

Cited By ~ 6

Author(s):

Annamaria Colao ◽

Bartolomeo Merola ◽

Diego Ferone ◽

Paolo Marzullo ◽

Gaetana Cerbone ◽

...

Keyword(s):

Growth Hormone ◽

Pituitary Adenomas ◽

Acute Administration ◽

Α Subunit ◽

Chronic Effects ◽

Igf I ◽

Thyroid Axis ◽

Acute And Chronic Effects ◽

Non Functioning Pituitary Adenomas

Colao A, Merola B, Ferone D, Marzullo P, Cerbone G, Longobardi S, Di Somma C, Lombardi G. Acute and chronic effects of octreotide on thyroid axis in growth hormone-secreting and clinically non-functioning pituitary adenomas. Eur J Endocrinol 1995;133:189–94. ISSN 0804–4643 The effect of somatostatin on thyroid function was studied in 12 patients with growth hormone (GH)-secreting and eight patients with clinically non-functioning adenomas (NFA) and normal pituitary/ thyroid axis; the patients were subjected to the administration of octreotide (OCT), which is a longacting somatostatin analog. All the patients received an acute test with 100 μg of OCT, both short term (1 month) and long term (6 months), with doses ranging from 300 to 600 μg/day, Serum thyroxine (T4). triiodothyronine (T3), free T4, free T3, thyroglobulin and basal and thyrotropin (TSH)-releasing hormone (TRH)-stimulated TSH were evaluated before and after 1 and 6 months of therapy. Circulating GH and insulin-like growth-factor I (IGF-I) in acromegalics and GH, IGF-I and α-subunit in NFA were assessed at baseline and every month. The acute administration of 100 μg of OCT significantly reduced the TSH response to TRH (p < 0.01) in both acromegalics and NFA. In all the patients OCT administration caused a significant decrease of GH, IGF-I and α-subunit levels (p < 0.01). In addition, after 1 month of therapy both baseline and TRH-induced TSH secretion were decreased significantly in acromegalics and NFA. After 6 months of therapy, baseline and TRH-induced TSH was still reduced in NFA. Conversely, in acromegalics, baseline TSH levels were increased while TSH response to TRH was inhibited. No change of T4, T3, free T4 and free T3 was observed in NFA, whereas a slight but significant increase of T4 and decrease of T3 was recorded in acromegalics. In conclusion, OCT does seem to possess long-term suppressive effects on TSH response to TRH, both in acromegalics and NFA. The lack of basal TSH level inhibition in acromegalics could depend on the restored peripheral conversion of T4 into T3 due to the normalized GH levels during long-term OCT administration. Annamaria Colao, Corso Europa 63, 80127 Napoli, Italy

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Acute and chronic effects of cardiac resynchronization in patients developing heart failure with long-term pacemaker therapy for acquired complete atrioventricular block

EP Europace ◽

10.1093/europace/eum119 ◽

2007 ◽

Vol 9 (10) ◽

pp. 869-874 ◽

Cited By ~ 28

Author(s):

M. Shimano ◽

Y. Tsuji ◽

Y. Yoshida ◽

Y. Inden ◽

N. Tsuboi ◽

...

Keyword(s):

Heart Failure ◽

Atrioventricular Block ◽

Cardiac Resynchronization ◽

Complete Atrioventricular Block ◽

Pacemaker Therapy ◽

Chronic Effects ◽

Developing Heart ◽

Acute And Chronic Effects ◽

Complete Atrioventricular

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The regulation of glutamine and ketone-body metabolism in the small intestine of the long-term (40-day) streptozotocin-diabetic rat

Biochemical Journal ◽

10.1042/bj2420061 ◽

1987 ◽

Vol 242 (1) ◽

pp. 61-68 ◽

Cited By ~ 14

Author(s):

M Watford ◽

E J Erbelding ◽

E M Smith

Keyword(s):

Small Intestine ◽

Ketone Body ◽

Ketone Bodies ◽

Streptozotocin Diabetes ◽

Diabetic Rats ◽

Glutamine Metabolism ◽

Diabetic Rat ◽

Coa Transferase ◽

Glutaminase Activity

The small intestine is the major site of glutamine utilization in the mammalian body. During prolonged (40-day) streptozotocin-diabetes in the rat there is a marked increase in both the size and the phosphate-activated glutaminase activity of the small intestine. Despite this increased capacity, intestinal glutamine utilization ceases in diabetic rats. Mean arterial glutamine concentration fell by more than 50% in diabetic rats, suggesting that substrate availability is responsible for the decrease in intestinal glutamine use. When arterial glutamine concentrations in diabetic rats were elevated by infusion of glutamine solutions, glutamine uptake across the portal-drained viscera was observed. The effect of other respiratory fuels on intestinal glutamine metabolism was examined. Infusions of ketone bodies did not affect glutamine use by the portal-drained viscera of non-diabetic rats. Prolonged diabetes had no effect on the activity of 3-oxoacid CoA-transferase in the small intestine or on the rate of ketone-body utilization in isolated enterocytes. Glutamine (2 mM) utilization was decreased in enterocytes isolated from diabetic rats as compared with those from control animals. However, glutaminase activity in homogenates of enterocytes was unchanged by diabetes. In enterocytes isolated from diabetic rats the addition of ketone bodies or octanoate decreased glutamine use. It is proposed that during prolonged diabetes ketone bodies, and possibly fatty acids, replace glutamine as the major respiratory fuel of the small intestine.

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