Cholinergic stimulation of phosphatidylinositol hydrolysis by rat corneal epithelium in vitro

Chymodenin, a basic porcine duodenal peptide, was administered to anesthetized rabbits intravenously or added to the medium bathing the isolated pancreas. In the 10(-8)M range, chymodenin rapidly increased chymotrypsinogen (ChTg) secretion, did not increase lipase secretion, and modestly enhanced protein secretion (which could be attributed primarily to augmented ChTg secretion). The increased ChTg output was too rapid to be the result of increased rates of protein synthesis and could not be attributed to the exocytosis os zymogen granule contents because of the enzyme-;pecific nature of the response. In contrast to shymodenin, cholinergic stimulation in vitro produced a relatively lipase-rich, chymotrypsinogen-poor secretion. Lipase and ChTg outputs, which varied relatively independently under unstimulated conditions, covaried in the presence of chymodenin. The existence of a duodenal peptide that produces an enzyme-specific response supports the hypothesis that the secretion of digestive enzymes during digestion is a highly regulated process in which the enzyme content of pancreatic secretion varies with differences in the composition of intestinal substrates.

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Antagonism by Some β-Adrenoceptor-Blocking Agents to Cholinergic Stimulation of Skeletal Muscle in vitro

Pharmacology ◽

10.1159/000137272 ◽

1979 ◽

Vol 18 (6) ◽

pp. 319-326

Author(s):

V.V. Kelkar ◽

R.S. Gupta&dagger; ◽

N.U. Jariwala ◽

N.J. Joshi

Keyword(s):

Skeletal Muscle ◽

Cholinergic Stimulation ◽

Beta Adrenoceptor ◽

Blocking Agents ◽

Stimulation Of

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Secretion of new digestive enzyme by pancreas with minimal transit time

American Journal of Physiology-Legacy Content ◽

10.1152/ajplegacy.1976.230.6.1499 ◽

1976 ◽

Vol 230 (6) ◽

pp. 1499-1503 ◽

Cited By ~ 11

Author(s):

SS Rothman

Keyword(s):

Protein Secretion ◽

Digestive Enzyme ◽

Secreted Protein ◽

Cholinergic Stimulation ◽

Rabbit Pancreas ◽

Intracellular Storage ◽

New Protein ◽

Storage Pools ◽

Stimulation Of

A small amount of labeled digestive enzyme is secreted within 5 min of adding radioactive leucine to whole rabbit pancreas in vitro. This rapid secretion of labeled protein suggests that some new protein is able to bypass intracellular storage pools and is secreted immediately. The amount of protein secreted this way varies inversely with overall protein secretion in the unstimulated state and is decreased as the result of cholinergic stimulation of protein secretion as well. Under the conditions studied, a mean of 2.5% of secreted protein is apparently not stored prior to secretion.

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Early Platelet-Collagen Interactions in Whole Blood and Their Modifications by Aspirin and Dipyridamole Evaluated by a New Method (Basic Wave)

Thrombosis and Haemostasis ◽

10.1055/s-0038-1660136 ◽

1985 ◽

Vol 54 (04) ◽

pp. 799-803 ◽

Cited By ~ 14

Author(s):

José Luís Pérez-Requejo ◽

Justo Aznar ◽

M Teresa Santos ◽

Juana Vallés

Keyword(s):

Whole Blood ◽

Ex Vivo ◽

Platelet Rich Plasma ◽

White Blood Cells ◽

Reversible Aggregation ◽

Inhibitory Compounds ◽

Rapid Generation ◽

Stimulation Of ◽

Collagen Stimulation

SummaryIt is shown that the supernatant of unstirred whole blood at 37° C, stimulated by 1 μg/ml of collagen for 10 sec, produces a rapid generation of pro and antiaggregatory compounds with a final proaggregatory activity which can be detected for more than 60 min on a platelet rich plasma (PRP) by turbidometric aggregometry. A reversible aggregation wave that we have called BASIC wave (for Blood Aggregation Stimulatory and Inhibitory Compounds) is recorded. The collagen stimulation of unstirred PRP produces a similar but smaller BASIC wave. BASIC’s intensity increases if erythrocytes are added to PRP but decreases if white blood cells are added instead. Aspirin abolishes “ex vivo” the ability of whole blood and PRP to generate BASIC waves and dipyridamole “in vitro” significantly reduces BASIC’s intensity in whole blood in every tested sample, but shows little effect in PRP.

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DER EINFLUSS VON RESERPIN AUF DIE ANTITHYREOIDALE WIRKUNG VON KALIUMPERCHLORAT

Acta Endocrinologica ◽

10.1530/acta.0.0390423 ◽

1962 ◽

Vol 39 (3) ◽

pp. 423-430

Author(s):

H. L. Krüskemper ◽

F. J. Kessler ◽

E. Steinkrüger

Keyword(s):

Thyroid Gland ◽

Male Rats ◽

Normal Male ◽

Tissue Respiration ◽

List Type ◽

Morphological Alterations ◽

Hormone Synthesis ◽

Stimulation Of

ABSTRACT 1. Reserpine does not inhibit the tissue respiration of liver in normal male rats (in vitro). 2. The decrease of tissue respiration of the liver with simultaneous morphological stimulation of the thyroid gland after long administration of reserpine is due to a minute inhibition of the hormone synthesis in the thyroid gland. 3. The morphological alterations of the thyroid in experimental hypothyroidism due to perchlorate can not be prevented with reserpine.

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EFFECT OF ACTINOMYCIN D ON TSH-INDUCED STIMULATION OF THYROIDAL PROTEIN SYNTHESIS IN THE RAT

Acta Endocrinologica ◽

10.1530/acta.0.0770064 ◽

1974 ◽

Vol 77 (1) ◽

pp. 64-70 ◽

Cited By ~ 9

Author(s):

Gustav Wägar

Keyword(s):

Protein Synthesis ◽

Actinomycin D ◽

The Other ◽

Leucine Incorporation ◽

Short Term ◽

Other Hand ◽

Thyroid Glands ◽

Translational Level ◽

Stimulation Of

ABSTRACT Whether the short-term regulation of thyroidal protein synthesis by TSH occurs at the transcriptional or the translational level was tested by measuring the effect of actinomycin D (act D) on the TSH-induced stimulation of L-14C-leucine incorporation into the thyroidal proteins of rats. TSH was injected 6 h before the rats were killed. The thyroid glands were then removed and incubated in vitro in the presence of L-14C-leucine for 2 h. The pronounced stimulation of leucine incorporation in the TSH-treated animals was depressed as compared with controls but still significant even when the animals had been pre-treated with 100 μg act D 24 and 7 h before sacrifice. On the other hand, act D strongly decreased incorporation of 3H-uridine into RNA. Short-term regulation of thyroidal protein synthesis by TSH appears to be partly but not wholly dependent on neosynthesis of RNA. Hence regulation may partly occur at the translation level of protein synthesis.

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