Calcium Efflux and Secretion of Α‐amylase From Rat Pancreas

Heisler, Seymour

doi:10.1111/j.1476-5381.1974.tb08607.x

Cited by 23 publications

(12 citation statements)

References 14 publications

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“…DBCAMP, which by itself is a weak pancreatic secretagogue, similarly does not stimulate calcium release (Heisler 1974;Fast and Tenenhouse 1996). The effects of those neuroleptics capable sf blocking both 45@a release, and amylase secretion evoked by carbachol, CCK-PZ, and A-23187, were tested on the secretory responses to DBCAMP, secretin, and VIP.…”

Section: H L~r~r Q T I X E H Ementioning

confidence: 94%

Stimulus–secretion coupling in exocrine pancreas: possible role of calmodulin

Heisler¹,

Chauvelot²,

Desjardins³

et al. 1981

Can. J. Physiol. Pharmacol.

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Many calcium-mediated effects in mammalian cells may be activated by calcium-calmodulin stimulated enzymes. These effects are inhibited by various antidepressant drugs which bind to and inactivate calmodulin. In the current study, calmodulin was identified by affinity chromatography and gel electrophoresis in the cytoplasm of dispersed rat pancreatic acinar cells. Its role in enzyme secretion was assessed by evaluating the effects of various antidepressants drugs on the enzyme secretory process. Chlorpromazine, trifluoperazine, thioridazine, chlorprothixene and amitriptyline inhibited amylase secretion stimulated by carbachol, A-23187, and cholecystokinin-pancreozymin but not that elicited by dibutyryl cyclic AMP secretin or vasoactive intestinal peptide (VIP). Haloperidol, sulpiride, phenobarbital, and ethanol were without effect on secretagogue-stimulated enzyme release. Only those agents which blocked secretion also inhibited 45Ca release stimulated by carbachol from isotope preloaded cells. The data suggest that calmodulin may have a functional role in pancreatic enzyme secretion.

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Section: H L~r~r Q T I X E H Ementioning

confidence: 94%

Stimulus–secretion coupling in exocrine pancreas: possible role of calmodulin

Heisler¹,

Chauvelot²,

Desjardins³

et al. 1981

Can. J. Physiol. Pharmacol.

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“…The nervous control of enzyme release has been emphasized recently by reports showing that atropine can prevent depolarization of the acinar cell , cellular cyclic GMP accumulation (Christophe, Frandsen, Conlon, Krishna & Gardner, 1976) and calcium efflux (Matthews, Petersen & Williams, 1973;Heisler, 1974) stimulated by cholinomimetic agents.…”

Section: Introductionmentioning

confidence: 99%

Comparative Inhibitory Effects of 3‐quinuclidinyl Benzilate (Qnb) and Atropine on Amylase Release From Rat Pancreas

Morisset¹,

Ng²,

Poirier³

1977

British J Pharmacology

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Secretion of amylase from rat pancreas stimulated by urecholine was studied in relation to its inhibition by atropine and 3‐quinuclidinyl benzilate (QNB). Urecholine‐induced secretion was completely abolished by atropine at 10−6 M and QNB at 10−8 M. Significant inhibition could be detected at 10−8 M atropine and 10−10 M QNB. The secretory response to pancreozymin was not blocked either by atropine or QNB. The inhibitory effect of QNB remained for at least 90 min after its removal from the incubation medium. It is concluded that QNB is 10 times more potent than atropine in inhibiting pancreatic amylase secretion induced by urecholine.

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“…The current study was designed to measure pancreatic membrane ATPase activity and to determine whether it was responsive to PZ and/or carbachol. Since dibutyryl cyclic AMP affects calcium flux in the pancreas (Heisler, 1974) we also studied the effect of this agent on the ATPase activity of isolated plasma membranes.…”

mentioning

confidence: 99%

Calcium-activated ATPase activity in a plasma membrane-rich preparation of rat pancreas

Forget

Heisler

1976

Clin Exp Pharmacol Physiol

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1. Calcium-stimulated ATPase activity was studied in a plasma membrane rich fraction of rat pancreas homogenate. 2. The enzyme is stimulated to the same maximum rate of ATP hydrolysis by either calcium or magnesium, but the apparent requirement for calcium is five-fold lower than for magnesium. 3. Maximum hydrolytic activity of the enzyme is not increased when additional magnesium is added to the optimal amount of calcium. 4. The enzyme does not require Na+ or K+ for its activation by Ca2+ and is not inhibited by ouabain or 2,4-dinitrophenol. 5. Pancreozymin, in concentrations which evoke secretion of zymogen protein, inhibits the calcium-stimulated ATPase. 6. Carbachol and dibutyryl cyclic AMP, in concentrations which increase the release of digestive proteins, do not alter the activity of the calcium-stimulated enzyme. 7. It is suggested that the plasma membrane calcium-activated enzyme, is not involved in the active calcium extrusion, previously reported to occur with use of the various pancreatic secretagogues tested.

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Calcium Efflux and Secretion of Α‐amylase From Rat Pancreas

Cited by 23 publications

References 14 publications

Stimulus–secretion coupling in exocrine pancreas: possible role of calmodulin

Stimulus–secretion coupling in exocrine pancreas: possible role of calmodulin

Comparative Inhibitory Effects of 3‐quinuclidinyl Benzilate (Qnb) and Atropine on Amylase Release From Rat Pancreas

Calcium-activated ATPase activity in a plasma membrane-rich preparation of rat pancreas

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