PERMISSIVE ROLE OF l-THYROXINE IN INDUCTION OF PANCREATIC AMYLASE BY CORTISOL IN NEONATAL RATS

Subcutaneous injection of cortisol (10 μg/g body wt daily for 5 days) into normal neonatal rats increased the activity of stomach pepsinogen after day 5. l-Thyroxine (T4; 0·2 μg/g body wt daily for 5 days) alone did not affect the activity but it somewhat enhanced the effect of cortisol. Even before day 5, when no effect of cortisol alone was observed, T4 plus cortisol increased pepsinogen activity. In adrenalectomized, thyroidectomized neonatal rats, injection of cortisol alone did not induce enzyme activity but cortisol together with T4 did induce it. Moreover, the increase in pepsinogen activity was depressed in rats thyroidectomized on day 10 but not in those thyroidectomized on day 15. These results suggest that T4 does not have a direct effect on the stomach but plays an important role in making the stomach responsive to glucocorticoids, resulting in increased pepsinogen activity.

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l-THYROXINE, CORTISOL AND DIET AFFECT THE LEVEL OF AMYLASE IN THE PAROTID GLAND OF DEVELOPING RATS

Journal of Endocrinology ◽

10.1677/joe.0.0870065 ◽

1980 ◽

Vol 87 (1) ◽

pp. 65-71 ◽

Cited By ~ 9

Author(s):

MASAYOSHI KUMEGAWA ◽

NORIHIKO MAEDA ◽

TOSHIHIKO YAJIMA ◽

TAISHIN TAKUMA ◽

EIKO IKEDA ◽

...

Keyword(s):

Body Weight ◽

Enzyme Activity ◽

Parotid Gland ◽

Amylase Activity ◽

Synergistic Effects ◽

Dietary Factors ◽

Adult Rats ◽

Early Increase ◽

Adrenalectomized Rats ◽

Intact Rats

The effects of cortisol (10 μg/g body weight) and l-thyroxine (T4; 0·2 μg/g body weight) on the activity of parotid gland amylase in young rats were investigated. Administration of cortisol or T4 for 5 consecutive days from day 5 after birth caused the precocious appearance of amylase, T4 having almost twice the effect of cortisol. Cortisol and T4 did not have synergistic effects. In thyroidectomized-adrenalectomized rats, T4 increased amylase activity but cortisol did not. The increase in enzyme activity after day 20 was much less in rats thyroidectomized on day 10 than in rats adrenalectomized on day 10. These results suggest that T4 has a direct effect on the early increase of amylase activity (days 15–25) and that the action of glucocorticoid requires the presence of endogenous thyroid hormones. The hormone-induced level of amylase in intact rats was less than that of normal adult rats. Forced weaning of intact rats resulted in a further increase in amylase activity, suggesting that further amylase accumulation (after day 25) may be due to dietary factors.

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Calcium ATPase and intestinal calcium transport in uremic rats

AJP Gastrointestinal and Liver Physiology ◽

10.1152/ajpgi.1980.238.5.g424 ◽

1980 ◽

Vol 238 (5) ◽

pp. G424-G428

Author(s):

H. Schiffl ◽

U. Binswanger

Keyword(s):

Enzyme Activity ◽

Atpase Activity ◽

Calcium Transport ◽

Calcium Atpase ◽

Intestinal Calcium Transport ◽

Identical Response ◽

Close Relationship ◽

Intact Rats

Calcium ATPase, an enzyme involved in intestinal calcium transport, was measured in homogenates of duodenal mucosal scrapings of normal and uremic rats. The effects of calcium deprivation and treatment with 1 alpha,25-dihydroxycholecalciferol [1,25-(OH)2D3] were investigated as well. Uremia decreased the enzyme activity and impaired the rise after calcium deprivation as observed in intact rats. The 1,25-(OH)2D3 treatment increased the enzyme activity in uremic animals and resulted in an identical response to calcium deprivation as observed in intact rats; parathyroidectomy abolished this effect. A striking correlation between everted duodenal gut sac calcium transport and calcium ATPase activity could be demonstrated for all groups of rats studied. It is concluded that the calcium ATPase activity is linked to the production of 1,25-(OH)2D3 as well as to an additional factor, probably parathyroid hormone. The close relationship between enzyme activity and in vitro calcium transport, even during constant physiological supplementation with 1,25-(OH)2D3, suggests an autonomous role of the calcium ATPase activity for mediation of calcium transport in the duodenum in addition to the well-known mechanisms related to vitamin D and its metabolites.

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THE EFFECT OF THYROID ADMINISTRATION ON THE PANCREATIC AMYLASE ACTIVITY OF HYPOPHYSECTOMIZED AND INTACT RATS

Canadian Journal of Biochemistry and Physiology ◽

10.1139/o63-157 ◽

1963 ◽

Vol 41 (6) ◽

pp. 1373-1379 ◽

Cited By ~ 2

Author(s):

Madelaine O. Maykut ◽

Margaret T. Nishikawara ◽

R. E. Haist

Keyword(s):

Body Weight ◽

Thyroid Gland ◽

Amylase Activity ◽

Total Activity ◽

Pancreatic Amylase ◽

Hypophysectomized Rats ◽

Dose Levels ◽

Marked Atrophy ◽

Intact Rats

The administration of desiccated thyroid gland to hypophysectomized rats prevented the marked atrophy of the pancreas which was consistently observed following hypophysectomy. Thyroid feeding at two dose levels led to a significant increase in the pancreatic amylase activity of hypophysectomized rats. This held whether the results were expressed as total activity or were given as activity per unit of body weight, per unit of pancreas, or per mg nitrogen. Except for the activity per unit of body weight, the amylase activity of the thyroid-treated hypophysectomized rats was significantly lower than the amylase activity in untreated, intact controls. In the thyroid-fed, hypophysectomized rats the amylase activity per unit of body weight was not significantly different from that of intact, untreated controls.Thyroid administration in intact rats resulted in a decrease in the pancreatic amylase activity.

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Regulation of renal Na-K-ATPase in the rat: effect of uninephrectomy

AJP Renal Physiology ◽

10.1152/ajprenal.1986.251.3.f506 ◽

1986 ◽

Vol 251 (3) ◽

pp. F506-F512 ◽

Cited By ~ 2

Author(s):

S. K. Mujais ◽

N. A. Kurtzman

Keyword(s):

Enzyme Activity ◽

Adrenal Gland ◽

Atpase Activity ◽

Thick Ascending Limb ◽

Medullary Thick Ascending Limb ◽

Collecting Tubule ◽

Pars Recta ◽

Intact Rats ◽

Cortical Collecting Tubule

This study has examined the temporal profile and the segmental localization along the rat nephron of the increase in Na-K-ATPase produced by uninephrectomy, and the role of the adrenal gland in the generation of the increase in enzyme activity. In adrenal-intact rats, an increase in Na-K-ATPase activity in the cortical collecting tubule (CCT) was observed at 1 wk (140 +/- 13% of sham, P less than 0.05) and sustained at 2 wk (140 +/- 8% of sham, P less than 0.05). In contrast, the enhancement of enzyme activity in the proximal convoluted tubule (PCT) was transient (at 1 wk: 164 +/- 20% of sham, P less than 0.05; and at 2 wk: 97 +/- 9% of sham, P greater than 0.5). No changes in Na-K-ATPase activity were observed in the other nephron segments studied: pars recta, medullary thick ascending limb, cortical thick ascending limb, distal convoluted tubule, and medullary collecting tubule. In adrenalectomized rats, CCT enzyme activity was lower than in adrenal-intact rats (761 +/- 84 vs. 1,984 +/- 276 pmol X mm-1 X h-1, P less than 0.001) and was not altered by uninephrectomy (849 +/- 91 pmol X mm-1 X h-1, NS). We conclude that the increase in Na-K-ATPase activity following uninephrectomy is restricted to two segments of the nephron and follows a distinctive pattern in each. In the PCT a transient enhancement in enzyme activity is observed, whereas in the CCT the increase in Na-K-ATPase is sustained and requires the presence of an intact adrenal gland.

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Effects of hypo- and hyperthyroidism on pancreatic TRH-degrading activity and TRH concentrations in developing rat pancreas

Acta Endocrinologica ◽

10.1530/acta.0.1060209 ◽

1984 ◽

Vol 106 (2) ◽

pp. 209-214 ◽

Cited By ~ 6

Author(s):

Sonia Aratan-Spire ◽

Bryan Wolf ◽

Paul Czernichow

Keyword(s):

Thyroid Hormone ◽

Thyroid Hormones ◽

Neonatal Period ◽

Fold Increase ◽

Thyroid Status ◽

Thyrotrophin Releasing Hormone ◽

Rat Pancreas ◽

High Concentrations ◽

Developing Rat

Abstract. High concentrations of thyrotrophin-releasing hormone (TRH) in the rat pancreas were detected during the first few days of life decreasing thereafter while pancreatic TRH-degrading activity (TRH-DA) absent at birth appeared on day 14 and increased to reach adult values by day 21. This period of life is also remarkable by the low level of circulating thyroid hormones. Since TRH-degrading activity may be thyroid hormone dependent it was of interest to study the effects of thyroid status fluctuations both on TRH-DA and TRH content during the neonatal period. In this study, hypo- and hyperthyroidism were induced by 6-n-propyl-2-thiouracil (PTU) and triiodothyronine (T3) respectively. Pancreatic TRH-DA and TRH concentrations were measured at different ages from birth until day 29, in treated animals and results compared to control age-matched rats. In hypothyroid rats, pancreatic TRH concentrations remained significantly higher after day 16 while TRH-DA was lower during the whole period studied. Following T3 treatment, pancreatic TRH concentrations decreased significantly from day 3 onwards. However, no significant changes were found for TRH-DA except a two-fold increase on day 28. These results suggest that two different mechanisms may account for thyroid hormones action: 1) a direct effect on pancreatic TRH 2) an inductive saturable effect on TRH-DA. Furthermore a fine tuner modulatory role of TRH-DA on TRH concentrations cannot be excluded.

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The Role of the Brain in the Regulation of Peripheral Organs–Noradrenaline Sources in Neonatal Rats: Noradrenaline Synthesis Enzyme Activity

Doklady Biochemistry and Biophysics ◽

10.1134/s1607672920040109 ◽

2020 ◽

Vol 493 (1) ◽

pp. 201-204

Author(s):

A. R. Murtazina ◽

Yu. O. Nikishina ◽

M. V. Ugrumov

Keyword(s):

Enzyme Activity ◽

Neonatal Rats ◽

Peripheral Organs ◽

Noradrenaline Synthesis ◽

The Brain

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Determination of pancreatic amylase activity by a radial diffusion assay

Canadian Journal of Physiology and Pharmacology ◽

10.1139/y70-109 ◽

1970 ◽

Vol 48 (11) ◽

pp. 758-761 ◽

Cited By ~ 2

Author(s):

André Bélanger ◽

Jean Perreault ◽

Yvon Couture ◽

Jacques Dunnigan

Keyword(s):

Reaction Zone ◽

Optical Density ◽

Amylase Activity ◽

Pancreatic Amylase ◽

Insulin Hypoglycemia ◽

Rat Pancreas ◽

Iodine Complex ◽

Radial Diffusion Assay ◽

Diffusion Assay

A technique for assay of amylase content in homogenates of rat pancreas is described. It is based on the measurement of the diameter of a "reaction zone" resulting from the action of the enzyme diffusing through a gel containing the substrate. The method is used to evaluate the amylase content of the pancreas of rats stimulated by feeding and by insulin-hypoglycemia. The results are compared with those obtained by a classic amyloclastic method, using the optical density of the starch-iodine complex.

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THE EFFECT OF THYROID ADMINISTRATION ON THE PANCREATIC AMYLASE ACTIVITY OF HYPOPHYSECTOMIZED AND INTACT RATS

Canadian Journal of Biochemistry and Physiology ◽

10.1139/y63-157 ◽

1963 ◽

Vol 41 (1) ◽

pp. 1373-1379 ◽

Cited By ~ 2

Author(s):

Madelaine O. Maykut ◽

Margaret T. Nishikawara ◽

R. E. Haist

Keyword(s):

Body Weight ◽

Thyroid Gland ◽

Amylase Activity ◽

Total Activity ◽

Pancreatic Amylase ◽

Hypophysectomized Rats ◽

Dose Levels ◽

Marked Atrophy ◽

Intact Rats

The administration of desiccated thyroid gland to hypophysectomized rats prevented the marked atrophy of the pancreas which was consistently observed following hypophysectomy. Thyroid feeding at two dose levels led to a significant increase in the pancreatic amylase activity of hypophysectomized rats. This held whether the results were expressed as total activity or were given as activity per unit of body weight, per unit of pancreas, or per mg nitrogen. Except for the activity per unit of body weight, the amylase activity of the thyroid-treated hypophysectomized rats was significantly lower than the amylase activity in untreated, intact controls. In the thyroid-fed, hypophysectomized rats the amylase activity per unit of body weight was not significantly different from that of intact, untreated controls.Thyroid administration in intact rats resulted in a decrease in the pancreatic amylase activity.

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Permissive role of neutrophils in pathogenesis of indomethacin-induced gastric lesions in rats

Gastroenterology ◽

10.1016/s0016-5085(01)82961-9 ◽

2001 ◽

Vol 120 (5) ◽

pp. A595-A595

Author(s):

M TAKEEDA ◽

Y KOMOIKE ◽

S KATO ◽

H MIMAKI ◽

K TAKEUCHI

Keyword(s):

Gastric Lesions ◽

Permissive Role

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