scholarly journals Thyroid hormone activated upper gastrointestinal motility without mediating gastrointestinal hormones in conscious dogs

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Nobuhiro Nakazawa ◽  
Makoto Sohda ◽  
Kyoichi Ogata ◽  
Seded Baatar ◽  
Yasunari Ubukata ◽  
...  
Keyword(s):  
Thyroid Hormone ◽  
Motor Activity ◽  
Thyroid Function ◽  
Gastrointestinal Motility ◽  
Gastrointestinal Hormones ◽  
Conscious Dogs ◽  
Phase Iii ◽  
High Dose ◽  
The Relationship ◽  
Upper Gastrointestinal

AbstractThis study was conducted to clarify the relationship between thyroid function and gastrointestinal motility. We established an experimental configuration in which the feedback of thyroid function was completely removed using conscious dogs. With hypothyroidism, time of phase I of interdigestive migrating contractions (IMC) was longer, time of phase II and phase III was significantly shortened, and both the continuous time of strong tetanic contraction at antrum and 10-h frequency of phase III counted from the first IMC after meal significantly decreased. Whereas, hyperthyroidism caused the opposite events to those with hypothyroidism. Furthermore, We found giant migrating contractions (GMC) occurred from the upper gastrointestinal tract when we administrated high dose of thyroid hormone. One GMC occurred from anal sides propagated to cardiac, and this propagation was similar to the emesis-like interdigestive motor activity, the other GMC occurred from oral sides propagated to anal sides and this was similar to the diarrhea-like interdigestive motor activity. We examined the relationship between thyroid function and gastrointestinal hormones including of ghrelin, GLP-1, and cholecystokinin (CCK). However, we could not find significant differences under different thyroid hormone status. This is the first report that thyroid hormone activated upper gastrointestinal motility without mediating gastrointestinal hormones.

scholarly journals Evaluation of changes in gastrointestinal motility caused by altered thyroid function in conscious dogs

2021 ◽  
Author(s):  
Nobuhiro Nakazawa ◽  
Makoto Sohda ◽  
Kyoichi Ogata ◽  
Seded Baatar ◽  
Yasunari Ubukata ◽  
...  
Keyword(s):  
Thyroid Hormone ◽  
Motor Activity ◽  
Thyroid Function ◽  
Gastrointestinal Motility ◽  
Gastrointestinal Hormones ◽  
Conscious Dogs ◽  
High Dose ◽  
Interdigestive Migrating Contractions ◽  
The Relationship ◽  
Upper Gastrointestinal

Abstract This study was conducted to clarify the relationship between thyroid function and gastrointestinal motility. We established an experimental configuration in which the feedback of thyroid function was completely removed using conscious dogs. With hypothyroidism, time of phase Ⅰ of interdigestive migrating contractions (IMC) was longer, time of phase Ⅱ and phase Ⅲ was significantly shortened, and both the continuous time of strong tetanic contraction at antrum and 10-hours frequency of phase Ⅲ counted from the first IMC after meal significantly decreased. Whereas, hyperthyroidism caused the opposite events to those with hypothyroidism. Furthermore, We found giant migrating contractions (GMC) occurred from the upper gastrointestinal tract when we administrated high dose of thyroid hormone. One GMC occurred from anal sides propagated to cardiac, and this propagation was similar to the emesis-like interdigestive motor activity, the other GMC occurred from oral sides propagated to anal sides and this was similar to the diarrhea-like interdigestive motor activity. We examined the relationship between thyroid function and gastrointestinal hormones including of ghrelin, GLP-1, and cholecystokinin (CCK). However, we could not find significant differences under different thyroid hormone status. This is the first report that thyroid hormone activated upper gastrointestinal motility without mediating gastrointestinal hormones.

scholarly journals Low serum selenium in pregnancy is associated with reduced T3 and increased risk of GDM

2021 ◽  
Vol 248 (1) ◽  
pp. 45-57
Author(s):  
Pierre Hofstee ◽  
Janelle James-McAlpine ◽  
Daniel R McKeating ◽  
Jessica J Vanderlelie ◽  
James S M Cuffe ◽  
...  
Keyword(s):  
Thyroid Hormone ◽  
Pregnant Women ◽  
Thyroid Function ◽  
Tertiary Care ◽  
Endocrine Disorders ◽  
Serum Selenium ◽  
Selenium Status ◽  
Increased Risk ◽  
The Relationship ◽  
Low Serum

Thyroid disorders are the most common endocrine disorders affecting women commencing pregnancy. Thyroid hormone metabolism is strongly influenced by selenium status; however, the relationship between serum selenium concentrations and thyroid hormones in euthyroid pregnant women is unknown. This study investigated the relationship between maternal selenium and thyroid hormone status during pregnancy by utilizing data from a retrospective, cross-sectional study (Maternal Outcomes and Nutrition Tool or MONT study) with cohorts from two tertiary care hospitals in South East Queensland, Australia. Pregnant women (n = 206) were recruited at 26–30 weeks gestation and serum selenium concentrations were assessed using inductively coupled plasma mass spectrometry. Thyroid function parameters were measured in serum samples from women with the lowest serum selenium concentrations (51.2 ± 1.2 µg/L), women with mean concentrations representative of the entire cohort (78.8 ± 0.4 µg/L) and women with optimal serum selenium concentrations (106.9 ± 2.3 µg/L). Women with low serum selenium concentrations demonstrated reduced fT3 levels (P < 0.05) and increased TPOAb (P < 0.01). Serum selenium was positively correlated with fT3 (P < 0.05) and negatively correlated with TPOAb (P < 0.001). Serum fT4 and thyroid-stimulating hormone (TSH) were not different between all groups, though the fT4/TSH ratio was increased in the low selenium cohort (P < 0.05). Incidence of pregnancy disorders, most notably gestational diabetes mellitus, was increased within the low serum selenium cohort (P < 0.01). These results suggest selenium status in pregnant women of South East Queensland may not be adequate, with possible implications for atypical thyroid function and undesirable pregnancy outcomes.

Pyloric contribution to antroduodenal resistance to flow in the conscious dog

1987 ◽  
Vol 253 (1) ◽  
pp. G72-G78 ◽  
Author(s):  
F. Mearin ◽  
F. Azpiroz ◽  
J. R. Malagelada
Keyword(s):  
Motor Activity ◽  
Phase I ◽  
Conscious Dogs ◽  
Phase Iii ◽  
Control Group ◽  
Conscious Dog ◽  
Motor Cycle ◽  
Interdigestive Motility ◽  
Specific Contribution

We have developed a pneumatic resistometer to monitor antroduodenal resistance to flow for prolonged periods of time in conscious dogs. To investigate the specific contribution of the pylorus to antroduodenal resistance we compared resistance during fasting in four control dogs and in four dogs with extramucosal pyloric myotomy (1.5 cm long). After pyloric myotomy, as in controls, resistance to flow changed cyclically, being lowest during phase I and highest during phase III of the interdigestive motor cycle. Pyloric myotomy decreased resistance during phase III. Atropine (0.1 mg X kg-1 X h-1) administered during motor quiescence (phase I) reduced resistance in the control group (P less than 0.05) but not in myotomized animals. Bethanechol(0.2 mg X kg-1 X h-1) significantly increased resistance in both groups (P less than 0.05). We conclude that antroduodenal resistance to flow is related to cyclic interdigestive motility. The pylorus is the predominant determinant of antroduodenal resistance during motor quiescence, but its contribution diminishes markedly during motor activity.

Free thyroid hormone index, thyroid hormone/thyroxin-binding globulin ratio, triiodothyronine uptake, and thyroxin-binding globulin compared for diagnostic value regarding thyroid function.

1983 ◽  
Vol 29 (1) ◽  
pp. 74-79 ◽  
Author(s):  
T J Wilke
Keyword(s):  
Thyroid Hormone ◽  
Thyroid Function ◽  
Diagnostic Value ◽  
Clinical Findings ◽  
Thyroid Function Tests ◽  
Free Thyroid Hormone ◽  
Age Related ◽  
Age Dependent ◽  
Uptake Test ◽  
The Relationship

Abstract The thyroid hormone/thyroxin-binding globulin (TBG) ratio and the free thyroid hormone index (FTI) were compared in 372 subjects classified according to age, sex, and biochemical and clinical findings. Age-related variations in thyroid function tests were investigated, as was the relationship between triiodothyronine uptake and TBG. Men, but not women, showed significant age-dependent changes in concentrations of thyroid hormones. FTI was as good as the thyroid hormone/TBG ratio in hyperthyroidism and was a better index of thyroid status in pregnancy, TBG deficiency, and hypothyroidism. In addition, the triiodothyronine uptake correlated extremely well with TBG (r = -0.95, p less than 0.001) and was very efficient in detecting decreased and significantly increased concentrations of TBG. I conclude that FTI is a better discriminator of functional status of the thyroid over a wider range of TBG values than is the thyroid hormone/TBG ratio. Further, the triiodothyronine uptake test produced diagnostic information equivalent to that of TBG estimation and thus should not be replaced in routine use.

scholarly journals 3,5-T2 alters murine genes relevant for xenobiotic, steroid, and thyroid hormone metabolism

2016 ◽  
Vol 56 (4) ◽  
pp. 311-323 ◽  
Author(s):  
Julika Lietzow ◽  
Janine Golchert ◽  
Georg Homuth ◽  
Uwe Völker ◽  
Wenke Jonas ◽  
...  
Keyword(s):  
Thyroid Hormone ◽  
Molecular Mechanisms ◽  
Target Genes ◽  
Phase Iii ◽  
Whole Body ◽  
High Dose ◽  
Thyroid Hormone Metabolism ◽  
Expression Of Genes ◽  
Genes Encoding ◽  
Novel Target

The endogenous thyroid hormone (TH) metabolite 3,5-diiodo-l-thyronine (3,5-T2) acts as a metabolically active substance affecting whole-body energy metabolism and hepatic lipid handling in a desirable manner. Considering possible adverse effects regarding thyromimetic action of 3,5-T2 treatment in rodents, the current literature remains largely controversial. To obtain further insights into molecular mechanisms and to identify novel target genes of 3,5-T2 in liver, we performed a microarray-based liver tissue transcriptome analysis of male lean and diet-induced obese euthyroid mice treated for 4 weeks with a dose of 2.5 µg/g bw 3,5-T2. Our results revealed that 3,5-T2 modulates the expression of genes encoding Phase I and Phase II enzymes as well as Phase III transporters, which play central roles in metabolism and detoxification of xenobiotics. Additionally, 3,5-T2 changes the expression of TH responsive genes, suggesting a thyromimetic action of 3,5-T2 in mouse liver. Interestingly, 3,5-T2 in obese but not in lean mice influences the expression of genes relevant for cholesterol and steroid biosynthesis, suggesting a novel role of 3,5-T2 in steroid metabolism of obese mice. We concluded that treatment with 3,5-T2 in lean and diet-induced obese male mice alters the expression of genes encoding hepatic xenobiotic-metabolizing enzymes that play a substantial role in catabolism and inactivation of xenobiotics and TH and are also involved in hepatic steroid and lipid metabolism. The administration of this high dose of 3,5-T2 might exert adverse hepatic effects. Accordingly, the conceivable use of 3,5-T2 as pharmacological hypolipidemic agent should be considered with caution.

Effects of CCK receptor blockade on intestinal motor activity in conscious dogs

1991 ◽  
Vol 260 (2) ◽  
pp. G315-G324 ◽  
Author(s):  
C. Niederau ◽  
M. Karaus
Keyword(s):  
Small Intestine ◽  
Motor Activity ◽  
Phase Ii ◽  
Physiological Role ◽  
Conscious Dogs ◽  
Phase Iii ◽  
Motor Patterns ◽  
Fed State ◽  
Specific Antagonist ◽  
Cck Antagonist

This study employed a cholecystokinin (CCK) antagonist to evaluate whether endogenous CCK regulates fasted and fed motor patterns of the small intestine. Experiments were performed in six conscious dogs, each in duplicate. Motor activity was recorded by six strain-gauge transducers implanted along the small intestine. The effects of the CCK analogue caerulein and the CCK antagonist loxiglumide were studied in fasted and fed states. Computer analysis determined contractile frequency and area under contractions. Caerulein given as an intravenous bolus 30 min after phase III dose dependently caused a burst of phasic contractions preceded by a retrograde giant contraction. Continuous intravenous infusion of 10 mg.kg-1.h-1 loxiglumide completely abolished the effects of 10 ng/kg caerulein, which increases plasma CCK immunoreactivity to postprandial levels. Loxiglumide, at 10 mg.kg-1.h-1, markedly reduced the increase in phasic contractions due to a supraphysiological dose of 50 ng/kg caerulein to 14 +/- 6(SD)% of the control without loxiglumide (P less than 0.01). The motor activity stimulated by the cholinesterase inhibitor neostigmine (10 micrograms/kg) was not altered by loxiglumide. Loxiglumide given in the fasted state decreased contractile frequency from 9.5 +/- 0.7 to 8.1 +/- 0.6/min and reduced the area under contractions during phase II to 81 +/- 5% of the control without loxiglumide (P less than 0.05). Loxiglumide also decreased contractile frequency during the fed state from 9.7 +/- 0.6 to 8.3 +/- 0.5/min and reduced the area under contractions to 78 +/- 6% of the control without loxiglumide (P less than 0.05). Thus loxiglumide acts as a specific antagonist of the actions of CCK on small intestinal motor activity in the dog. Loxiglumide, at a dose that abolishes actions of endogenous CCK, significantly decreased fasting motor activity during phase II. Loxiglumide also significantly reduced motor responses to feeding but did not prevent interruption of migrating motor complex cycle by a meal. CCK plays a physiological role in regulation of fasting and fed motor activity of small intestine, although other factors in addition to CCK mediate meal-induced motor activity.

Response of migrating motor complex to variation of fasting intraluminal content

1992 ◽  
Vol 263 (4) ◽  
pp. G533-G537
Author(s):  
D. Smith ◽  
B. Waldron ◽  
F. C. Campbell
Keyword(s):  
Gastrointestinal Tract ◽  
Motor Activity ◽  
Phase Ii ◽  
Migrating Motor Complex ◽  
Phase Iii ◽  
Liquid Content ◽  
Volume Changes ◽  
Contraction Amplitude ◽  
Motor Complex ◽  
Upper Gastrointestinal

The characteristics of the phases of the migrating motor complex (MMC) were studied in the antrum, duodenum, and jejunum after alteration of intraluminal gas and acaloric fluid in 17 healthy volunteers. Aspiration of gas and fluid from the upper gastrointestinal tract reduced motor activity. In the antrum and duodenum, phase II contraction amplitude decreased, while in the duodenum and jejunum, the duration of phase II decreased and phase I increased. Phase III contraction frequency decreased in the duodenum only. Intragastric instillation of gas caused an increase of phase II duration and contraction amplitude in all regions. Similar effects were observed after intragastric instillation of fluid. Fasting periodic motor activity is responsive to volume changes of intraluminal gas and acaloric liquid content.

Intragastric administration of rikkunshito stimulates upper gastrointestinal motility and gastric emptying in conscious dogs

2012 ◽  
Vol 48 (5) ◽  
pp. 611-619 ◽  
Author(s):  
Mitsuhiro Yanai ◽  
Erito Mochiki ◽  
Atsushi Ogawa ◽  
Hiroki Morita ◽  
Yoshitaka Toyomasu ◽  
...  
Keyword(s):  
Gastric Emptying ◽  
Gastrointestinal Motility ◽  
Conscious Dogs ◽  
Intragastric Administration ◽  
Upper Gastrointestinal

Neural mediation of the motilin motor effect on the human antrum

1997 ◽  
Vol 272 (1) ◽  
pp. G71-G76 ◽  
Author(s):  
M. Boivin ◽  
L. R. Pinelo ◽  
S. St-Pierre ◽  
P. Poitras
Keyword(s):  
Healthy Volunteers ◽  
Gastrointestinal Motility ◽  
Mode Of Action ◽  
Low Dose ◽  
Phase Iii ◽  
High Dose ◽  
Contractile Effect ◽  
Antroduodenal Motility ◽  
Pharmacological Blockade ◽  
Stimulation Of

To elucidate the mode of action of motilin on the stimulation of human gastrointestinal motility, we studied the effect of exogenous motilin during muscarinic or serotoninergic pharmacological blockade. Manometric recording of the interdigestive antroduodenal motility was carried out in 27 healthy volunteers until the appearance of a spontaneous antral phase III. The tested blocker was then administered intravenously and was followed 30 min later by a 10-min infusion of synthetic human motilin (50 ng/kg). Motilin administered on a background of saline induced a premature phase III migrating from the antrum to the duodenum in every tested subject (n = 5). A low dose of atropine (5 micrograms.kg-1.h-1 for 90 min) inhibited the motilin effect in two of five subjects [not significant (NS)], whereas a high dose of atropine (15 micrograms/kg given in 30 min) blocked the motilin-induced premature antral phase III in all instances (n = 5, P < 0.01). Exogenous motilin given with low-dose ondanseton (8 mg given in 15 min followed by 1 mg/h for 90 min) or high-dose ondansetron (32 mg given in 30 min) was without effect in three of seven (NS) or in two of five (NS) subjects, respectively. During the administration of 15 micrograms/kg atropine, when exogenous motilin always failed to induce a premature antral phase III motor, a phase III-type activity was generated at the duodenum in four of five subjects. We conclude that the induction by motilin of phase III activity in human antrum is dependent on muscarinic mediation and that the contractile effect of motilin on human duodenum involves a noncholinergic mechanism, different therefore from the antral pathway.

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