Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:3.4.23.15 (renin)
 35,795 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Peak exercise capacity (Peak VO2), neurohormonal changes, ventricular enlargement and ejection fraction are among the most important determinants of prognosis in congestive heart failure. However, the inter-relation between these parameters is unknown. We, therefore, correlated these indices in patients with hemodynamically severe congestive heart failure (NYHA class II, pulmonary artery wedge pressure 25 +/- 2 mm Hg, cardiac index 2.5 +/- 0.2 l/min/m2, ejection fraction 43 +/- 2% and fractional shortening 19 +/- 1%). Peak VO2 measured directly during exercise by breath to breath expiratory gas analysis using a metabolic cart was 23 ml/min/kg. Plasma epinephrine (E) and norepinephrine (NE) were measured by high performance liquid chromatography (HPLC) and plasma renin activity (PRA), aldosterone (Aldo), cortisol, prolactin, growth hormone, anti-diuretic hormone (ADH) and antinatriuretic peptide (ANP) by radioimmunoassay. Ejection fraction was measured by echocardiography. There was no relation between peak VO2 and any of the neurohormones E: r = -0.43, NE: r = -0.43, ANP: r = -0.49, Cortisol: r = -0.37, ADH: r = -0.07, Aldo: r = -0.45, 2 tail critical value 0.55. PRA showed a modest correlation (r = -0.61). Similarly, there was no relation between ejection fraction or degree of ventricular enlargement and any of the other indices (r = -0.05). We conclude that although peak VO2, neurohormonal profile and ventricular function are important individual prognostic determinants, there seems to be no direct relation between them.
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PMID:Relation between major indices of prognosis in patients with chronic congestive heart failure: studies of maximal exercise oxygen consumption, neurohormones and ventricular function. 128 16

The effect of atrial natriuretic hormone (ANH) on metoclopramide-induced stimulation of aldosterone was studied in eight healthy young men after 3 days of controlled diet (150 mEq sodium, 100 mEq potassium). Baseline values were obtained after subjects had remained sitting for 1 hour. Subjects then received 2-hour infusions of placebo, dopamine (2 micrograms/kg/min), ANH (0.6 pmol/kg/min), and ANH plus dopamine. One hour after the beginning of each infusion, a 10 mg intravenous bolus of metoclopramide was given. Prolactin levels increased 10-fold after metoclopramide with placebo infusion, and about 50% of this stimulation was abolished by preinfusion with dopamine. ANH preinfusion did not suppress prolactin release. Urinary sodium excretion increased prominently during dopamine infusion. ANH at this dose had no effect on natriuresis. The dopamine dose given had almost no effect on metoclopramide-induced aldosterone secretion, whereas ANH infusions, which resulted in approximate doubling of plasma ANH levels, suppressed aldosterone. This study supports a role of ANH in aldosterone regulation, even at nonnatriuretic doses, and suggests that ANH is acting not only through the renin-angiotensin system but under certain conditions has significant physiologic action directly on glomerulosa cells.
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PMID:Effect of atrial natriuretic hormone on metoclopramide-induced stimulation of aldosterone. 132 36

Cocaine-induced enhancement of motor activity and extracellular dopamine concentrations exhibits sensitization upon repeated exposure. In this study, the neuroendocrine responses to cocaine were examined following cocaine pretreatment regimens which have been shown to produce behavioral sensitization. Adult male rats were injected with cocaine (15 mg/kg, IP) once daily for 14 days, followed by a dose-response challenge with cocaine (1-15 mg/kg, IP) either 18 hours or 7 days after the final pretreatment injection. Blood was collected 15 minutes following injections for radioimmunoassay of ACTH, corticosterone, prolactin, and renin. Cocaine increased plasma ACTH and corticosterone, while it decreased prolactin and renin concentrations. Pretreatment with cocaine for 2 weeks did not alter any of these endocrine responses after either the 18 hour or 7 day interval between pretreatment and challenge injections. In contrast, sensitization to the locomotor stimulant effects of cocaine was observed on the final day of pretreatment injections, and 7 days later. These data suggest that these endocrine effects of cocaine do not exhibit sensitization following repeated cocaine exposure.
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PMID:Neuroendocrine responses to cocaine do not exhibit sensitization following repeated cocaine exposure. 132 86

This study was undertaken to examine whether several of the hormones that can be released by activation of serotonin receptors will be affected by long-term cocaine administration. Male rats received cocaine injections (15 mg/kg, IP) twice daily for 7 days. Forty-two hr after the last cocaine injection, the rats were challenged with increasing doses (0, 1, 5, 10 mg/kg, IP) of the 5-HT1/5-HT2 agonist MK-212 (6-chloro-2-[1-piper-azinyl]-pyrazine). The following observations were made: (1) cocaine reduced the rate of body weight gain; (2) cocaine inhibited the stimulatory effect of MK-212 on plasma vasopressin, oxytocin, and prolactin concentrations and on plasma renin activity and concentration; (3) cocaine did not inhibit the stimulatory effect of MK-212 on plasma ACTH or corticosterone concentrations. The data indicate that a wide-spectrum 5-HT (serotonin) agonist such as MK-212 can reveal differential neuroendocrine responses. This effect could be related to cocaine-induced changes in the different 5-HT receptor subtypes that regulate the secretion of these hormones.
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PMID:Effect of cocaine injections on the neuroendocrine response to the serotonin agonist MK-212. 133 9

Endocrine responses to the serotonin (5-HT) 5-HT1C/5-HT2 agonist (+/-)-1-(2,5-dimethoxy-4-iodophenyl)-2-aminopropane (DOI) were utilised to evaluate cocaine-induced alterations in postsynaptic 5-HT receptor function. Rats received cocaine HCl (0, 5 or 15 mg/kg i.p.) twice daily for 7 days. Effects of DOI (0, 0.5, 2 or 10 mg/kg i.p.) on plasma adrenocorticotropic hormone (ACTH), corticosterone, prolactin, oxytocin and renin concentrations were assessed 42 h after the final cocaine injection. DOI dose dependently increased the plasma concentrations of each hormone. Cocaine potentiated the DOI-induced elevations of plasma ACTH, corticosterone and prolactin concentrations. In contrast, the oxytocin response was reduced, and the renin response was unaltered by cocaine exposure. The data suggest that 5-HT2 receptor-mediated responses for ACTH, corticosterone and prolactin secretion become supersensitive following repeated cocaine. In contrast, the 5-HT2 receptor-mediated response for oxytocin secretion is subsensitive. The cocaine-induced changes in postsynaptic 5-HT receptor function are likely a consequence of deficits in the function of 5-HT nerve terminals, that we have documented previously.
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PMID:Repeated cocaine modifies the neuroendocrine responses to the 5-HT1C/5-HT2 receptor agonist DOI. 133 68

Several classes of drugs that modify serotonin (5-HT) neurotransmission are either currently used, or are being evaluated for their potential use in the treatment of anxiety, schizophrenia, and depression. 5-HT1A agonists are considered potential anxiolytics, while some atypical antipsychotics are potent 5-HT2 antagonists (and also have modest dopamine D2 affinity). Furthermore, there is a diverse group of serotonergic drugs that may be effective antidepressants. Secretion of ACTH, corticosterone/cortisol, prolactin, renin, oxytocin and vasopressin are stimulated by activation of different 5-HT receptor subtypes, while other neurotransmitter receptors also influence the secretion of these hormones. We compared the receptor binding profiles of 5-HT anxiolytics, antipsychotics and antidepressants with their endocrine effects. These comparisons could aid in understanding both the therapeutic and side effects of these drugs.
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PMID:Endocrine and receptor pharmacology of serotonergic anxiolytics, antipsychotics and antidepressants. 135 27

Ipsapirone is an anxiolytic drug and a serotonin1A (5-HT1A) agonist. The aim of the present study was to investigate the effects of low doses of ipsapirone on the hormonal and behavioral response to three stress procedures: immobilization, forced swim and conditioned emotional response (CER). We examined the effect of ipsapirone (0.1, 0.5 or 1.0 mg/kg) on plasma renin concentration (PRC), adrenal corticotropic hormone (ACTH), corticosterone, prolactin and defecation in rats exposed to immobilization, forced swim or CER stress. All three stressors significantly elevated all the hormone levels (P less than 0.01). Immobilization-induced elevations of PRC, and corticosterone were inhibited by the highest doses of ipsapirone (0.5 and 1 mg/kg, i.p.). However, ipsapirone did not modify the immobilization-induced elevations of plasma ACTH, prolactin or defecation. Ipsapirone was relatively ineffective at reducing the endocrine responses to forced swim. Ipsapirone reduced some, but not all of the hormonal responses to CER stress. CER-induced elevations of corticosterone and prolactin were not inhibited by ipsapirone. However, the ACTH response to CER was significantly (P less than 0.01) inhibited by all doses of ipsapirone and the highest dose of ipsapirone attenuated the renin response. In contrast with the hormonal responses, ipsapirone inhibited all of the behavioral responses to CER stress. Ipsapirone inhibited CER-induced freezing behavior and defecation, while dose-dependently reversing the suppressive effect of CER on exploring, grooming and rearing behaviors. In conclusion, there is a dissociation between the influence of ipsapirone on the endocrine and behavioral responses to CER stress. Ipsapirone also has differential effects on the neuroendocrine response to the three stressors studied. Ipsapirone was most effective in attenuating the hormonal responses to CER, followed by immobilization and swim stress. Of the hormones studied, the stimulation of renin secretion after exposure to the three stressors was most sensitive to ipsapirone, while corticosterone and prolactin were the least sensitive to ipsapirone.
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PMID:Comparison of neuroendocrine and behavioral effects of ipsapirone, a 5-HT1A agonist, in three stress paradigms: immobilization, forced swim and conditioned fear. 135 56

Evidence suggests that activation of 5-HT1A receptors leads to inhibition of 5-HT2-mediated behavior. The purpose of this study was to investigate the interaction between 5-HT1A and 5-HT2 receptor-mediated hormone secretion. Rats were pretreated with the 5-HT1A agonists buspirone (0, 0.5, 2.0 mg/kg, i.p.), 8-OH-DPAT (0, 0.05, 0.2 mg/kg, s.c.) or ipsapirone (0, 1.0, 2.5 mg/kg, i.p.), 45 min before decapitation. The 5-HT2 agonist DOI was administered (0-10 mg/kg, i.p.) 15 min after injection of the 5-HT1A agonists. The three 5-HT1A agonists differentially altered the DOI-induced increase of concentrations of hormone in plasma. None of the three 5-HT1A agonists influenced the basal levels of renin, ACTH and prolactin but 8-OH-DPAT and buspirone increased the basal level of corticosterone in plasma. Also, 8-OH-DPAT increased the effects of DOI on the concentration of ACTH in plasma but ipsapirone and buspirone did not. None of the 5-HT1A agonists significantly affected DOI-induced increase of concentration of corticosterone in plasma. Buspirone and 8-OH-DPAT potentiated the effect of DOI on prolactin in plasma, but ipsapirone did not. Ipsapirone potentiated the effect of DOI on the concentration of renin in plasma but this effect was not observed in 8-OH-DPAT- and buspirone-pretreated rats. The results do not support the hypothesis for a functional interaction between 5-HT1A and 5-HT2 receptors, since the three 5-HT1A agonists did not have the same influence on the hormonal effects of DOI.
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PMID:Neuroendocrine responses to the serotonin2 agonist DOI are differentially modified by three 5-HT1A agonists. 135 39

In aggregate cell cultures of 15- to 20-day-old rat pituitary maintained in serum-free medium, luteinizing hormone-releasing hormone (LHRH) (10 nM) stimulated prolactin (PRL) release, confirming our previous results and those of others with serum-supplemented medium. Since angiotensin II (AII) stimulates PRL release and a renin-angiotensin system is expressed in gonadotrophs, LHRH stimulation of PRL release might be mediated by AII. To evaluate this hypothesis, the influence of (Sar1,Ala8)AII and (Sar1,Ile8)AII two peptide AII receptor antagonists, of DUP753, a nonpeptide and stable AII receptor antagonist, of a converting enzyme inhibitor, and of angiotensinogen on LHRH-induced PRL release was tested in various in vitro conditions of 15- to 20-day-old female rat pituitary. In aggregates maintained in serum-free medium with or without dexamethasone (DEX) and triiodothyronine (T3), or maintained in serum-supplemented medium, the effect of LHRH on PRL release was not affected by (Sar1Ala8)AII (0.1 microM), (Sar1,Ile8)AII (10 microM) or DUP753 (10 microM). Only a high dose (10 microM) of (Sar1,Ala8)AII attenuated the LHRH-induced PRL release. The latter attenuation was seen only with aggregates cultured in the DEX/T3 medium and not with aggregates cultured in the presence of serum. A dose of 1 or 10 nM (Sar1,Ala8)AII also failed to block the effect of LHRH used at 1 nM. In contrast, (Sar1,Ala8)AII dose dependently as well as DUP753 (10 microM) abolished the AII-induced PRL release. (Sar1,Ala8)AII also failed to affect the LHRH-induced PRL release in pituitary cell aggregates from 6-week-old male rats. However, in aggregates from both immature and 6-week-old rats, (Sar1,Ala8)AII provoked a small and statistically significant attenuation of the LHRH-induced PRL release when a 100 nM dose of LHRH was used. In freshly isolated hemipituitaries from 5-day-old rats, (Sar1,Ala8)AII (1 or 10 microM) did not affect the LHRH- (10 nM) induced PRL release. In single cells obtained by redispersion of aggregates and mounted in a Biogel P2 column, LHRH still stimulated PRL release. Again this effect could not be blocked by DUP753. Treatment of aggregate cell cultures with the angiotensin-converting enzyme inhibitor captopril or with angiotensinogen did not alter the LHRH-induced PRL release. It is concluded that AII is not the paracrine factor mediating the effect of LHRH at low nanomolar doses on PRL release, at least not through the classical AII receptor. The involvement of AII acting on a non-(Sar1,Ala8)AII-sensitive receptor cannot be excluded and warrants further investigation.
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PMID:Stimulation of prolactin secretion from rat pituitary by luteinizing hormone-releasing hormone: evidence against mediation by angiotensin II acting through a (Sar1-Ala8)-angiotensin II-sensitive receptor. 140 72

A complex of investigation was performed in 30 males with newly diagnosed prostatic cancer (stages T2NOMO-T3NO-1MO) before treatment with estrogens, 2-3 months and 1 year after its start. The complex included evaluation of blood lipid spectrum (HDL, LDL, VLDL, triglycerides), hemostasis (coagulation, platelet aggregation, fibrinolysis), hormonal profile (blood hydrocortisone, aldosterone, testosterone, estradiol, STH, FSH, LH, prolactin, plasma renin activity), central and intracardiac hemodynamics, ECG. 66 healthy men of advanced age served control. It was found that estrogen therapy affected blood lipid metabolism, leading to impairment of physiological correlation between HDL and triglycerides, increased blood levels of VLDL and triglycerides. Long-term estrogen treatment brought about enhancement of hemocoagulation and platelet aggregation. Hormonal shifts involved hyperprolactinemia, hypersomatotropism, hypercorticism, aldosterone hypersecretion, proportional androgens-estrogens alterations. Hormonal abnormalities produce side effects in estrogen-treated CHD and hypertonic patients: negative ECG readings indicative of deteriorated coronary circulation and hypertensive episodes, central hemodynamic disorders, respectively. In view of possible cardiovascular damage related to estrogen therapy, a differentiated approach is proposed which would allow a long-term estrogen treatment free of relevant complications.
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PMID:[The assessment of the state of the blood lipid spectrum, hemostasis, hormonal homeostasis and hemodynamics in the early diagnosis and drug correction of the cardiovascular changes in prostatic cancer patients undergoing estrogen therapy]. 141 45


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