Effects of Diltiazem on Guinea Pig Portal Vein in Hypertonic Solution

Takenaga, Hideyuki; Magaribuchi, Tetsuo; Nakajima, Hiromichi

doi:10.1254/jjp.28.457

Cited by 19 publications

(10 citation statements)

References 23 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…In isolated myocardium (7,8) and vascular (9)(10)(11)(12) or intestinal (13)(14)(15)(16) smooth muscles, it has been reported that this compound antagonizes calcium ion which is essential for muscle contraction, thus producing a decrease in the contractile force. Such a calcium antagonistic property of diltiazem has been shown in isolated pancreatic B-cell (1): the glucose-induced insulin secretion from the isolated islets of Langerhans from rats was suppressed by diltiazem and this effect was counteracted by increasing extracellular concentration of calcium ion.…”

Section: Discussionmentioning

confidence: 99%

“…It has been reported that diltiazem produced potent relaxing effects on the constrictor responses of various isolated vascular strips to spasmogens (9)(10)(11)(12). The concentration of diltiazem which inhibited the contraction of these vascular preparations by 50% was less than 10-6 M. On the other hand, a dose of 10-5M of diltiazem was required to induce a similar degree of inhibition in glucose-induced insulin secretion, as shown in the preceding in vitro (1) and present perfusion experiments.…”

Section: Discussionmentioning

confidence: 99%

See 1 more Smart Citation

Effect of diltiazem on insulin secretion

Yamaguchi

Akimoto

Nakajima

et al. 1979

Japanese Journal of Pharmacology

Self Cite

View full text Add to dashboard Cite

Abstract-Effect of diltiazem on insulin secretion was investigated in the perfused rat pancreas. Experiments were also carried out in anesthetized dogs and conscious rats with and without glucose loading.In the perfused rat pancreas, diltiazem reduced both glucose and tolbutamide-induced insulin secretion and these effects of diltiazem were reversed with removal of the compound. Inhibition of the glucose-induced insulin secretion caused by diltiazem was counteracted by increasing the concentration of calcium ion. In experiments on intact animals, diltiazem at vasoactive doses produced no significant influence on the basal level of plasma insulin or glucose-induced insulin secretion.These data taken together with findings in previously reported work suggest that diltiazem reduces insulin secretion from pancreatic B-cells in vitro possibly by the calcium-antagonistic property, while the compound exhibits practically no inhibitory action on the insulin secretion in vivo.In a preceding paper (1), it was shown that in isolated islets of Langerhans from rats, diltiazem produced a concentration-dependent inhibition of the release of insulin following stimulation with glucose. This inhibitory effect of diltiazem was antagonized with increasing concentrations of extracellular calcium ion. We suggested that diltiazem may suppress the glucose-induced insulin secretion by reducing free calcium ion concentration in B-cells.In the present study, the time course for change in insulin secretion from rat pancreas was followed using a perfusion method and the dynamic aspects of the inhibitory effect by diltiazem were studied. In vivo effects of diltiazem on the insulin secretion were also studied in dogs and rats with and without glucose loading. MATERIALS AND METHODS1. Perfusion of rat pancreas: The perfused rat pancreas was prepared according to the method described by Sussman et al. (2) with slight modification. Male Sprague-Dawley rats (about 450 g) were anesthetized with sodium pentobarbital (50 mg/kg i.p.) and the abdominal cavity was opened. All abdominal vessels except for the superior mesenteric artery and celiac axis were ligated and cut. A portion of the duodenum tightly adhering to the pancreas was left intact. The thoracic aorta was cannulated to a point just superior of the celiac axis and the perfusate was allowed to flow through the pancreas and a portion of the small intestine. The effluent was continuously collected through a cannulated portal vein at one to two min intervals. At the end of the experiments, the perfusion circuit was confirmed to be complete by perfusion with Evans blue. The perfusate was Krebs-bicarbonate

show abstract

Section: Discussionmentioning

confidence: 99%

Section: Discussionmentioning

confidence: 99%

Effect of diltiazem on insulin secretion

Yamaguchi

Akimoto

Nakajima

et al. 1979

Japanese Journal of Pharmacology

Self Cite

View full text Add to dashboard Cite

show abstract

“…Inhibition of the Ca2+ influx by diltiazem has been suggested in experiments with mecha nical and electrical activities of the isolated guinea pig portal vein (8). On the other hand, Greenberg et al (9) …”

mentioning

confidence: 99%

A comparison of the effects of diltiazem and nitroglycerin on the norepinephrine-induced contractions in the isolated femoral artery and vein.

Nakajima

Nosaka

1983

Jpn.J.Pharmacol

Self Cite

View full text Add to dashboard Cite

“…relaxes the vascular smooth muscle (4,10) and reduces the myocardial contractile force (5) due to its calcium antagonistic property. It has been reported that the va-,odilating activity of diltiazem was not the same among various vascular smooth muscles, being more potent in the coronary artery than in the thoracic aorta and femoral artery (10).…”

Section: Diltiazemmentioning

confidence: 99%

“…Diltiazem is a potent coronary vasodilator with calcium antagonistic activity (1)(2)(3)(4)(5). Among various vascular beds tested, the vasodilating effect of diltiazem was especially remarkable in the coronary and vertebral arteries (6,7).…”

mentioning

confidence: 99%

Cerebral vasodilation and spasmolytic activity of diltiazem in anesthetized animals.

1982

Self Cite

View full text Add to dashboard Cite

Abstract-The effects of diltiazem on the cerebral blood flow and cere brovascular spasm were studied in pentobarbital anesthetized animals. In Rhesus monkeys, the common carotid and internal carotid blood flow were measured by an electromagnetic flowmeter. Diltiazem (10-300 ug/ kg, i.v.) dose-dependently increased both the common carotid and internal carotid blood flow, and the increase in internal carotid blood flow persisted for a longer period than that in the common carotid blood flow. In dogs, regional blood flow in the cerebral cortex (rCBF) was measured by means of the hydrogen gas clearance method. Diltiazem (20 ug/kg/min, i.v.) increased rCBF by about 20% of the control during the infusion, and the increase in rCBF was still continued 40 min after the infusion was stopped. In cats, the basilar artery was exposed by craniotomy through the transcervico-transclival approach, and vasospasm was induced by topical administration of 5-HT, PGF2. and incubated blood. Diltiazem, either applied topically to the artery (100 ag/ml) or infused continuously into the femoral vein (20 or 40 ug/kg/min), suppressed the vasoconstriction evoked by the spasmogen.

show abstract

Effects of Diltiazem on Guinea Pig Portal Vein in Hypertonic Solution

Abstract: Abstract-Effects of diltiazem were investigated on the isolated portal vein of the guinea pig in hypertonic solution. Hyperosmolarity was produced by sucrose.

Cited by 19 publications

References 23 publications

Effect of diltiazem on insulin secretion

Effect of diltiazem on insulin secretion

A comparison of the effects of diltiazem and nitroglycerin on the norepinephrine-induced contractions in the isolated femoral artery and vein.

Cerebral vasodilation and spasmolytic activity of diltiazem in anesthetized animals.

Contact Info

Product

Resources

About