Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Pivot Concepts:
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Target Concepts:
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Drug
Enzyme
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Query: EC:3.4.15.1 (
ACE
)
18,300
document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)
The purpose of these investigations was to determine whether the aminopeptidase B and leucine aminopeptidase inhibitor bestatin, the
chymase
inhibitor chymostatin, the calpain inhibitor E-64, and the neutral serine protease inhibitor leupeptin affect the
angiotensin converting enzyme
(
ACE
) activity in T-lymphocytes.
ACE
activity in homogenates of T-lymphocytes or in intact T-lymphocytes in suspension was measured by determining fluorimetrically histidyl-leucine, formed from the conversion of hippuryl-histidyl-leucine, coupled with ophtaldialdehyde. The effect of various concentrations (10(-9) to 10(-3) mol/L) of the angiotensin-converting enzyme inhibitors lisinopril and captopril and of the various protease inhibitors on
ACE
activity was studied. Lisinopril and captopril reduced the
ACE
activity in homogenates of T-lymphocytes in a concentration-dependent manner. Lisinopril exhibited a more pronounced inhibition of
ACE
in T-lymphocytes than did captopril. Chymostatin and E-64 had no effect on the
ACE
activity in T-lymphocytes, whereas leupeptin inhibited its activity in a dose-dependent fashion. Bestatin, on the contrary, increased the
ACE
activity in homogenates of T-lymphocytes as well as in intact T-lymphocytes in proportion to the concentration. Our data showed that the
ACE
activity in T-lymphocytes was stimulated by bestatin and inhibited by leupeptin, whereas chymostatin and E-64 did not affect the
ACE
activity in T-lymphocytes.
...
PMID:Effect of protease inhibitors on angiotensin-converting enzyme activity in human T-lymphocytes. 1082 6
Possible involvement of mast cells in pulmonary sarcoidosis has been suggested, however whether mast cells are involved in cutaneous sarcoidosis remains unknown. We undertook a morphological study of mast cells in the lesional skin from 17 patients with cutaneous sarcoidosis using immunohistochemical methods. Mast cells were present in non-parenchymal fibrous areas, but not in granulomatous areas, in the biopsy specimens from the cutaneous lesions. However, there were no significant differences between the number of mast cells in the lesional skin and that in non-lesional skin from the patients. Mast cells containing substantial quantities of both tryptase and
chymase
(MC(TC) cells) were present in 41% of the patients, and cells containing tryptase but not
chymase
(MC(T) cells) were present in 59% of patients. All patients of the former group showed systemic manifestations of the disease concomitantly. Serum
angiotensin I-converting enzyme
levels were elevated in 71.4% of the former group, and in 30% of the latter group. This study for the first time demonstrated that mast cells were present in non-parenchymal fibrous areas of the cutaneous lesions of sarcoidosis, and the mast cell subtypes may be related to systemic manifestations.
...
PMID:Mast cells in the cutaneous lesions of sarcoidosis: their subtypes and the relationship to systemic manifestations. 1096 Jul 79
We investigated the levels of the angiotensin II-forming enzymes,
chymase
and
angiotensin converting enzyme
(
ACE
), in dog grafted veins, and studied the effect of an angiotensin II type 1 receptor antagonist, L-158,809, on vascular proliferation in the grafted veins. The right external jugular vein was grafted to the ipsilaterial carotid artery. In the group treated with L-158,809, the drug (10 mg/kg per day, p.o.) were administered orally from 7 days before the operation to 28 days after it, while the others were administrated placebo. In the placebo-treated group, the
chymase
activity in the grafted veins was increased about 10-fold and the
ACE
activity was doubled. The areas of intima and media were significantly increased in the grafted veins in the placebo-treated group. L-158,809 significantly reduced the intimal area of the grafted veins. An angiotensin II receptor antagonist, L-158,809, prevented the vascular proliferation in the grafted veins, and the development of the proliferation may depend on activation of local angiotensin II formation.
...
PMID:Angiotensin II receptor antagonist, L-158,809, prevents intimal hyperplasia in dog grafted veins. 1113 44
The possible involvement of the local angiotensin system in ganglionic functions was investigated in the canine cardiac sympathetic ganglia. Positive chronotropic responses to preganglionic stellate stimulation at high frequencies, after intravenous administration of pentolinium plus atropine, were inhibited by the nonpeptide angiotensin AT(1) receptor antagonist forasartan or the
angiotensin I-converting enzyme
inhibitor captopril, whereas the rate increases elicited by the postganglionic stellate stimulation and norepinephrine given intravenously failed to be inhibited by these antagonists. The levels of endogenous immunoreactive angiotensin II, as determined by radioimmunoassay in the incubation medium of the stellate and inferior cervical ganglia, were increased after the high-frequency preganglionic stimulation of the isolated ganglia. The increment of the peptide was also antagonized by the pretreatment with captopril but not by a
chymase
inhibitor, chymostatin. The expression of angiotensinogen mRNA was observed in the stellate ganglion, adrenal, liver, and lung but not in the ovary and spleen. The expression of the mRNA in the stellate and inferior cervical ganglia increased after high-frequency preganglionic stimulation of the in vivo dogs for a period of 1 hour. These results indicate that an intrinsic
angiotensin I-converting enzyme
-dependent angiotensin system exists in the cardiac sympathetic ganglia, which is activated by high-frequency preganglionic stimulation.
...
PMID:Upregulation of immunoreactive angiotensin II release and angiotensinogen mRNA expression by high-frequency preganglionic stimulation at the canine cardiac sympathetic ganglia. 1113 82
Recently, a
chymase
-dependent angiotensin (Ang) II-forming pathway was found in human cardiovascular tissues, and the significance of this pathway in the pathogenesis of some cardiovascular diseases was suggested. The present study examined the ratio of
angiotensin converting enzyme
(
ACE
) to
chymase
-dependent Ang II formation in various isolated vessels from monkeys, dogs and rats. In all of the examined vessels, the addition of KCl at a concentration of 50 mM could induce a maximal contraction. Except for monkey coronary artery and rat renal and femoral artery, the addition of Ang I could induce transitory contractions, whereas the force of contractions in these vessels was quite different. The sensitivity to Ang II in these vessels was similar to that for Ang I. In monkey gastroepiploic and mesenteric arteries, about 70% of the Ang I-induced contraction was suppressed by
chymase
inhibition, while it was suppressed about 50% in monkey renal, femoral and carotid arteries. In dog renal arteries, about 65% of the Ang I-induced contraction was suppressed by
chymase
inhibition, while it was suppressed by about 30% in other dog arteries. In contrast, in all rat arteries, Ang I-induced contractions were completely suppressed by treatment with
ACE
inhibitor alone. We concluded that regional differences in the response to Ang I exist in vascular tissues, and the ratio of
ACE
- to
chymase
-dependent Ang II formation is different in the various vessels.
...
PMID:The functional ratio of chymase and angiotensin converting enzyme in angiotensin I-induced vascular contraction in monkeys, dogs and rats. 1120 18
The development of pharmacological agents that block the renin-angiotensin system (RAS) specifically have helped to define all the components of the system and their contribution to blood-pressure control and to the pathogenesis of hypertension, congestive heart failure and chronic renal failure. The angiotensin converting-enzyme inhibitors (ACEi) are among all available drugs that interfere with the RAS, the most efficient, so far, in the treatment of several cardiovascular diseases, with comfortable posologic schemes and an acceptable safety profile. The most important difference between them are more related to pharmacokinetic profile rather than to pharmacodynamic characteristics. With the use of ACEi the interference with other neurohumoral systems is unavoidable and the controversy has been pharmacologically and clinically installed. With the advent of oral selective AT1 angiotensin II receptor blockers (ARB) the pharmacological interference became eventually much more selective. Their antihypertensive efficacy is identical and their tolerability is better than that showed by ACEi. The ARBs differ mainly in their pharmacokinetics and in their binding capacity to the AT1 angiotensin receptor. The results of several ongoing clinical trials will show if the ARBs as ACEi will be capable to protect target-organs and to promote a significant reduction in cardiovascular morbility and mortality. In parallel there is an intense experimental and clinical research with other groups of drugs which also markedly interfere with RAS: renin inhibitors,
chymase
inhibitors and simultaneous inhibitors of vasopeptidases (
ACE
, endothelin converting-enzyme, neutral endopeptidase). From the pharmacological point of view, it is now possible to block effectively RAS with some relevant clinical results that will be certainly widen in the near future.
...
PMID:[Angiotensin converting enzyme inhibitors (ACEIs) and angiotensin II receptor antagonists. Pharmacologic features]. 1130 8
Renin-angiotensin-aldosterone systems play a critical role in the development and progression of cardiovascular diseases, and inhibitors of angiotensin-converting enzyme have proven effective for the treatment of these diseases. Since angiotensin II receptor antagonists can inhibit the effects of angiotensin II via
ACE
-independent pathways, e.g.,
chymase
, they were considered to be more effective than ACEIs. On the other hand,
ACE
inhibitors can increase bradykinin, and thus, nitric oxide, which may cause potent cardioprotection, inhibition of smooth muscle proliferation and attenuation of inflammation mechanisms. It appears that angiotensin II receptor antagonists and ACEIs may mediate cardioprotection in different ways. This is the rationale to explore the possibility of a combined administration of both drugs for the treatment of chronic heart failure and other cardiovascular pathology. In this review we try to analyze the role of
ACE
, kinins and
chymase
inhibition in the pathophysiology and treatment of cardiovascular diseases.
...
PMID:Interactions of angiotensin-converting enzyme, kinins and nitric oxide in circulation and the beneficial effects of ACE inhibitors in cardiovascular diseases. 1134 78
Roles of each angiotensin II producing enzymes of each of the angiotensin II-producing enzymes were reviewed based on experimental models. In vascular tissues, angiotensin II is potentially cleaved from angiotensin I by
angiotensin converting enzyme
(
ACE
) and
chymase
. It has been confirmed that vascular tissues of humans, monkeys, dogs and hamsters have a
chymase
-dependent angiotensin II-forming pathway. Much like other hypertensive models, hamster hypertensive models show high levels of vascular
ACE
activity, but not
chymase
activity. In hypertensive hamsters, administration of either an
ACE
inhibitor or an angiotensin II type 1 (AT1) receptor antagonist resulted in similar reductions in blood pressure, suggesting that
chymase
is not involved in the maintenance of high blood pressure in this model. In monkeys fed a high-cholesterol diet,
ACE
activity was increased in the atherosclerotic lesions, and an
ACE
inhibitor and an AT1 receptor antagonist prevented atherosclerosis to a similar degree, suggesting that
ACE
may be mainly involved in the development of atherosclerosis. After balloon injury in dog vessels, both
ACE
and
chymase
activities were locally increased about 3-fold in the injured arteries, and an AT1 receptor antagonist was effective in preventing the intimal formation, but an
ACE
inhibitor was ineffective. In dog grafted veins, the activities of
chymase
were increased 15-fold, but those of
ACE
were increased only 2-fold, and the intimal formation was suppressed by either an AT1 receptor antagonist or a
chymase
inhibitor. In the normal vascular tissues,
ACE
plays a crucial role for angiotensin II production, whereas
chymase
is stored in mast cells in an inactive form. Chymase acquires the ability to form angiotensin II following mast cells activation followed by mast cells activation by a strong stimulus such as occurs in catheter-injury or grafting. Together, these results indicate that
chymase
plays a major role in the vascular angiotensin II-generating system, particularly in cases of vascular injury.
...
PMID:Local angiotensin II-generating system in vascular tissues: the roles of chymase. 1140 39
Angiotensin Converting Enzyme (ACE) inhibitors represent a major advance in the treatment of: hypertension, and generally speaking, in cardiovascular prevention; myocardial infarction; cardiac failure. They have a cardio and vascular protective action by tending to correct hypertension, left ventricular hypertrophy and remodelling, endothelial dysfunction, arterial smooth muscle proliferation and thrombotic phenomena. However, besides the cough that this therapeutic class engenders, a major question remains unanswered: is there resistance to this family of drugs? In other words, does left ventricular remodelling and arterial smooth muscle proliferation continue with regular treatment at the prescribed dosages? The synthesis of angiotensin II does not only depend on the
angiotensin converting enzyme
but also on the quality of angiotensin I and the presence of other enzymes such as
chymase
. A secondary increase of angiotensin II with ACE inhibitor therapy may reflect insufficient blockade of the renin-angiotensin system or a synthesis of angiotensin II by an alternative pathway to the converting enzyme. In vivo measurement of ACE inhibition shows that blockade of the renin-angiotensin system is automatically limited due to the very accurate regulation of angiotensin II concentrations.
...
PMID:[Resistance to ACE inhibitors. Myth or reality?]. 1160 63
Chymase may play an important role in vascular proliferation, as shown by in-vitro experiments, but the role of
chymase
in vivo has been unclear. In this study, we investigated the effect of a novel
chymase
inhibitor, NK3201, on this proliferation in dog grafted veins. NK3201 inhibited human and dog chymases, but not rabbit
ACE
. NK3201 suppressed the Ang I-induced vascular contraction in isolated dog arteries in the presence of an
ACE
inhibitor, and the IC50 value of chymostatin and NK3201 in dog artery was 320 nM. In dog, the concentration of NK3201 in blood was about 10 microM at 24 h after oral administration of the drug (5 mg/kg). In the group treated with NK3201, each dog was administered orally 5 mg/kg per day from 5 days before to the day before the removal of the grafted veins. Each dog underwent right common carotid artery bypass grafting with the ipsilaterial external jugular vein. By 28 days after grafting, a significant vascular proliferation was observed in the grafted veins and the
chymase
activity was also increased significantly. Treatment with
chymase
inhibitor significantly suppressed the proliferation of the grafted veins and the increased
chymase
activity. In this study, we demonstrate for the first time that oral administration of a specific
chymase
inhibitor, NK3201, appears useful for preventing vascular proliferation.
...
PMID:Oral administration of a specific chymase inhibitor, NK3201, inhibits vascular proliferation in grafted vein. 1166 34
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