Edoardo Guastamacchia

Università degli Studi di Bari Aldo Moro, Bari, Apulia, Italy

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Publications (73)102.44 Total impact

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    ABSTRACT: Background & aim: Hereditary Coproporphyria (HCP) is characterized by abdominal pain, neurologic symptoms and psychiatric disorders, even if it might remain asymptomatic. The pathophysiology of both neurologic and psychiatric symptoms is not fully understood. Therefore, aiming to evaluate a possible role of brain blood flow disorders, we have retrospectively investigated cerebral perfusion patterns in Single Photon Emission Computed Tomography (SPECT) studies in HCP patients. Patients & methods: We retrospectively evaluated the medical records of patients diagnosed as being affected by HCP. A total of seven HCP patients had been submitted to brain perfusion SPECT study with 99mTc-Exametazime (hexamethylpropyleneamine oxime, HMPAO) or of its functionally equivalent 99mTc-Bicisate (ECD or Neurolite) according with common procedures. In 3 patients the scintigraphic study had been repeated for a second time after the first evaluation at 3, 10 and 20 months, respectively. All the studied subjects had been also submitted to an electromyographic and a Magnetic Resonance Imaging (MRI) study of the brain. Results: Mild to moderate perfusion defects were detected in temporal lobes (all 7 patients), frontal lobes (6 patients) and parietal lobes (4 patients). Occipital lobe, basal ganglia and cerebellar involvement were never observed. In the three subjects in which SPECT study was repeated, some recovery of hypo-perfused areas and appearance of new perfusion defects in other brain regions have been found. In all patients electromyography resulted normal and MRI detected few unspecific gliotic lesions only in one patient. Discussion & Conclusions: Since perfusion abnormalities were usually mild to moderate, this can probably explain the normal pattern observed at MRI studies. Compared to MRI, SPECT with 99mTc showed higher sensitivity in HCP patients. Changes observed in HCP patients who had more than one study suggest that transient perfusion defects might be due to a brain artery spasm possibly leading to psychiatric and neurologic symptomatology, as already observed in patients affected by acute intermittent porphyria. This observation, if confirmed by other well designed studies aiming to demonstrate a direct link between artery spasm, perfusion defects and related symptoms could lead to improvements in HCP treatments.
    No preview · Article · Dec 2015
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    ABSTRACT: Subclinical Hypothyroidism can be associated with the onset of Chronic Heart Failure (CHF), because it can favour two frequent conditions that can evolve in CHF: coronary heart disease and hypertension; it can also alter both cardiovascular morphology and function leading to CHF progression in patients already affected by CHF through mechanisms still not completely understood. Aim of this paper is to review the possible pathogenetic mechanisms explaining the influence of subclinical hypothyroidism on the onset and progression of CHF.
    No preview · Article · Dec 2015
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    ABSTRACT: Selenium and iodine are essential for thyroid hormone synthesis and function. Selenium, in form of selenocysteine, is found either in the catalytic center of enzymes involved in the protection of the thyroid gland from free radicals originating during thyroid hormone synthesis, and in three different iodothyronine deiodinases catalyzing the activation and the inactivation of thyroid hormones. Iodine is an essential constituent of thyroid hormones and its deficiency causes different disorders that include goiter, hypothyroidism, reduced fertility and alteration in growth, physical and neurological development. These two micronutrients could be involved in the pathogenesis of autoimmune thyroid diseases, a spectrum of pathological conditions including Hashimoto's thryoiditis, post-partum thyroiditis, the so-called painless thyroiditis, Graves' disease and Graves' ophtalmopathy. Aim of this paper is to review the role played by selenium and iodine in autoimmune thyroiditis.
    No preview · Article · Dec 2015 · Endocrine Metabolic & Immune Disorders - Drug Targets(Formerly Current Drug Targets - Immune Endocrine & Metabolic Disorders)
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    ABSTRACT: (131)Iodine is used both to ablate any residual thyroid tissue or metastatic disease and to obtain whole-body diagnostic images after total thyroidectomy for differentiated thyroid cancer (DTC). Even though whole-body scan is highly accurate in showing thyroid residues as well as metastases of DTC, false positive results can be found, possibly leading to diagnostic errors and unnecessary treatments. This paper reviews the physiological and pathological processes involved as well as the strategy to recognize and rule out false positive radioiodine images.
    No preview · Article · Oct 2015 · Endocrine
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    ABSTRACT: The aim of this retrospective observational study was to evaluate whether adding liraglutide to lifestyle changes, metformin (Met) and testosterone replacement therapy (TRT), by means of improving weight and glycaemic control, could boost erectile function in type 2 diabetic obese men with overt hypogonadism and erectile dysfunction (ED) in a 'real-life setting'. Forty-three obese, diabetic and hypogonadal men (aged 45-59 years) were evaluated because of complaining about the recent onset of ED. They were subdivided into two groups according to whether hypogonadism occurred after puberty (G1; n = 30: 25 with dysfunctional hypogonadism and 5 with acquired hypogonadotropic hypogonadism) or before puberty (G2; n = 13: 10 with Klinefelter's syndrome and 3 with idiopathic hypogonadotropic hypogonadism). Both G1 and G2 patients were given a combination of testosterone (T) [testosterone undecanoate (TU) 1000 mg/every 12 weeks] and Met (2000-3000 mg/day) for 1 year. In the poor responders (N) to this therapy in terms of glycaemic target (G1N: n = 16; G2N: n = 10), liraglutide (L) (1.2 μg/day) was added for a second year, while the good responders (Y) to T + Met (G1Y: 14/30 and G2Y: 3/13) continued this two drugs regimen therapy for another year. All patients were asked to fill in the International Index of Erectile Function (IIEF 15) questionnaire before starting TU plus Met (T1) and after 12 months (T2) and 24 months (T3) of treatment. Patients underwent a clinical examination and a determination of serum sex hormone binding globulin (SHBG), total testosterone (T) and glycosylated haemoglobin (HbA1c) at T1, T2 and T3. At T2, each patient obtained an improvement of ED (p < 0.01) and of the metabolic parameters without reaching, however, the glycaemic goals [HbA1c = >7.5% (>58 mmol/mol)], while T turned out to be within the range of young men. L added to TU and Met regimen in G1N and G2N allowed these patients to reach not only the glycaemic target [HbA1c = <7.5% (<58 nmol/mol)] and a significant reduction in body weight (p < 0.01), but also a further increase in SHBG (p < 0.05) and T (p < 0.01) plasma levels as well as a significant increment of IIEF score (T3). Conversely, at T3 G1Y and G2Y, who received the combined therapy with TRT and Met for the second year, showed a partial failure of that treatment given that there was no improvement of the IIEF score and they showed a significant rise in serum HbA1c (p < 0.05) and weight (p < 0.04) compared with the assessments at T2. These results suggest that TRT could improve clinical and metabolic parameters in obese, type 2 diabetic men with ED and overt hypogonadism (independently of when T deficit occurred). Furthermore, in case of insufficient metabolic control the addition of L to TRT and Met regimen allows to achieve serum T levels in the range of healthy men, as well as to reach glycaemic target and to lower weight, leading to a considerable improvement of ED.
    No preview · Article · Oct 2015 · Andrology
  • M Iovino · N Iovine · F Mondillo · E Guastamacchia · B Licchelli · VA Giagulli · V Triggiani
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    ABSTRACT: Besides changes in pituitary hormones secretion observed during the acute phase of stroke as an adaptive response to injury or an effect of drugs, a true hypopituitarism due to ischemic and/or hemorrhagic damage at the hypothalamus and/or pituitary gland can develop after a stroke. We report a case of a 72-year-old woman showing clinical signs and laboratory data suggesting a secondary adrenal insufficiency following a recent acute brain ischemia. Cortisone therapy significantly improved this pituitary dysfunction. Therefore, clinicians must pay attention to the hypothalamic-pituitary axis in neurocritical patients because hormonal replacement therapy may be life-saving.
    No preview · Article · Sep 2015

  • No preview · Article · May 2015
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    ABSTRACT: Thyroid disease and diabetes mellitus, the most common disorders in endocrine practice, are not infrequently associated in the same subject. An altered thyroid function may affect glucose tolerance and worsen metabolic control in patients with diabetes. Thyrotoxicosis increases the risk of hyperglycemic emergencies, while a clinically relevant hypothyroidism may have a detrimental effect on glycemic control in diabetic patients. The association of alterations in thyroid function with diabetes mellitus may adversely affect the risk of cardiovascular and microvascular complications resulting from diabetes. Moreover, the treatments used for both diabetes and thyroid disease, respectively, can impact one other. Finally, multinodular goiter, but not thyroid carcinoma, was shown to be more prevalent in type 2 diabetes mellitus. Aim of the present Position Statement is to focus on the evidence concerning the association of thyroid disease and diabetes mellitus and to provide some practical suggestions for an updated clinical management.
    No preview · Article · Nov 2014 · Endocrine
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    ABSTRACT: The regulation of neurohypophyseal peptides secretion reflects the convergence of a large number of afferent neural pathways on vasopressinergic and oxytocinergic neurons of supraoptic (SON) and paraventricular nuclei (PVN). In addition to afferent input, vasopressin and oxytocin can also exert an autocrine regulation of neuronal activity. In fact, magnocellular neurons (MCNs) of SON and PVN are able to secrete these hormones not only at the endings of their terminal axons, but also from their dendrites and this local release, by activating a range of ion gated, ion channel and G protein coupled receptors (GPCRs), partecipate in pre- and post-synaptic modulation of neural activity of MCNs. In this review we analyzed VP and OT gene expression, synaptogenesis of MCNs in the SON and PVN, glial regulation of SON and PVN, transient receptor potential vanilloid cation channels, GPCRs, estrogen receptors, neuromodulators of SON and PVN functions and aquaporin 2 involved in the control of neurohypophyseal hormones secretion and related possible pharmacological targets-
    Full-text · Article · Oct 2014 · Current Pharmaceutical Design
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    ABSTRACT: We report the case of a young woman affected by hypothyroidism due to Hashimoto's thyroiditis, previously well compensated with a full replacement therapy (150 mcg/day of levothyroxine), presenting a clinical picture of myxedema, with a TSH=650 mU/L. Two years before she had started a dialysis treatment because of a chronic renal failure and she had been treated for the last 18 months with sevelamer carbonate, a phosphate binder. No improvement of clinical conditions nor reduction in TSH serum levels were obtained by increasing the dose of levothyroxine up to 300 mcg/day, whereas the euthyroidism was finally restored by administering the first morning dose of sevelamer carbonate at least 4 hours after the levothyroxine administration. This case shows that sevelamer carbonate, in analogy with what has been already reported for sevelamer hydrochloride, can interfere with levothyroxine absorption leading to a condition of hypothyroidism in patients previously well compensated with a given replacement dose.
    No preview · Article · Sep 2014 · Endocrine Metabolic & Immune Disorders - Drug Targets(Formerly Current Drug Targets - Immune Endocrine & Metabolic Disorders)
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    ABSTRACT: Afferent renal nerves stimulate vasopressin (VP) secretion by activation of VPergic neurons of SON and PVN. Intrarenal infusion of bradykinin (BK), which excites afferent renal nerves, increases VP release. However, BK is also a potent intrarenal vasodilator hence BK may modulate VPsecretion stimulating its release via afferent renal nerves and inhibiting its renal effects as intrarenal vasodilator via a paracrine control. BK impaired the mechanism of phosphorilation that induces the traslocation of vescicles containing aquaporin-2 to the apical plasma membrane thus inhibiting the osmotic water permeability of collecting duct cells provoked by VP via its V2 receptor, In addition, BKB2 receptor knockout mice exhibit decreased urine output and increased urine osmolality following water deprivation. Oxytocin (OT) increases urine volume and sodium excretion in rats. Icatibant, a BKB2 antagonist, suppress these effects showing that BK mediates diuresis and natriuresis induced by OT. Infusion of OT down-regulated myometrial OT and BK receptors indicating the existence of a common final pathway of OT and BK in the contractile responsiveness of uterine myometrial cells
    No preview · Article · Jun 2014
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    ABSTRACT: Rates of depression are significantly increased in diabetic patients, and even more in the elderly. About 20-30 % of patients with diabetes suffer from clinically relevant depressive disorders, 10 % of which being affected by the major depression disorder. Moreover, people with depression seem to be more prone to develop an associated diabetes mellitus, and depression can worsen glycemic control in diabetes, with higher risk to develop complications and adverse outcomes, whereas improving depressive symptoms is generally associated with a better glycemic control. Thus, the coexistence of depression and diabetes has a negative impact on both lifestyle and quality of life, with a reduction of physical activity and an increase in the request for medical care and prescriptions, possibly increasing the healthcare costs and the susceptibility to further diseases. These negative aspects are particularly evident in the elderly, with further decrease in the mobility, worsening of disability, frailty, geriatric syndromes and increased mortality. Healthcare providers should be aware of the possible coexistence of depression and diabetes and of the related consequences, to better manage the patients affected by these two pathological conditions.
    No preview · Article · Jun 2014 · Endocrine
  • Vincenzo Triggiani · Vito Angelo Giagulli · Edoardo Guastamacchia
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    ABSTRACT: Context: An empty sella is a relatively common condition, often being an incidental finding at MRI or CT scan. It can develop because of the intrasellar herniation of Cerebro-spinal Fluid (CSF) and arachnoid membrane through an absent or rudimentary diaphragm sellae in concomitance of a sudden and even transient increment of intracranial pressure, leading to a picture in which the pituitary is flattened along the floor of the sella. Case description: A young female with headache, nausea, dizziness, diplopia and visual impairment showed an empty sella on MRI and increased CSF pressure at the lumbar puncture. After an initial improvement, there was a progressive worsening of the headache, especially in orthostatic position, with transient relief after bed rest and hydration. At MRI the empty sella was no longer evident, cerebellar tonsils were displaced in the occipital foramen and there was an impregnation of the meninges after contrast medium, a picture of CSF hypotension, probably due to the previously performed lumbar puncture causing a fistula with leak of CSF and consequent disappearance of the empty sella. The patient gradually improved after being submitted to epidural blood patch. Conclusions: The case here reported demonstrates that an empty sella can be a reversible condition in rare cases. Its disappearance can be due to the reduction in intracranial pressure caused by the lumbar puncture itself. The changes in the characteristics of the headache, in particular its worsening in the orthostatic position, should lead to the suspicion of CSF leak through a fistula and consequent intracranial hypotension, a dangerous and sometimes life-threatening condition.
    No preview · Article · Apr 2014
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    ABSTRACT: This study examined whether the AR-CAG repeat length might affect clinical characteristics (testis volume) seminal parameters (sperm count and its mobility) along with hormonal serum profile [FSH, LH, Testosterone (T) and Inhibin B (InhB)] both in idiopathic male infertility (IM) and in infertility due to a previous condition of cryptorchidism (CryM) or to Y chromosome long arm microdeletions (YM). Observational study without intervention(s). One hundred and ten IM patients [90 idiopathic olizoospermic males (IOM) and 20 idiopathic azoospermic males (IAM)], 19 CryM male and 10 YM patients were included. Sixty-one age-matched healthy men who had fathered within 3 years were involved representing the control group (FM). AR-CAG repeats stretch was significantly longer in IOM (p < 0.05), CryM (p < 0.05) and YM (p < 0.001) than FM. When the AR-CAG repeat tracts were subdivided in three subgroups according to the length of CAG repeats tract assessed in fertile subjects (the one with the middle (n 19-21) belonging to the 25 and 75 % inter-quartile, the ends belonging to the <25 % inter-quartile and >75 % inter-quartile, respectively), there was a statistically significant difference of distribution of AR-CAG tract length among fertile and different groups of infertile men (p = < 0.0005; chi-square test). Moreover, the subgroup of AR-CAG repeat stretch with 22-28 triplets was associated with lower levels of InhB both in idiopathic oligozoospermic (Scheffe, Bonferroni and Dunett tests p = < 0.01) and azoospermic men (Scheffe, Bonferroni and Dunett test p = < 0.05), while, when FM and men with idiopathic infertility were gathered in a single group, both the subgroup of AR- CAG tract with 15-18 repeats and the one with 22-28 repeats are associated with lower testis volume, reduced sperm count and serum InhB levels. Our study showed that the outliers of AR-CAG repeat length seem to influence the function of AR, affecting testis volume and Sertoli cell function and consequently sperm production in both fertile and idiopathic infertile men.
    Full-text · Article · Apr 2014 · Journal of Assisted Reproduction and Genetics
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    ABSTRACT: In addition to release of vasopressin (VP) and oxytocin (OT) from terminal axons, magnocellular neurons (MCNs) of supraoptic (SON) and paraventricular nuclei (PVN) are able to release these hormones from their dendrites. This local release plays a role in pre- and post-synaptic modulation of MCNs thus showing an autocrine regulation of neural activity via dendritic release of VP and OT by activation of a range of ion gated, ion channel and G protein coupled receptors (GPCRs). In this review we analyzed VP and OT gene expression, synaptogenesis of MCNs in the SON and PVN, transient receptor potential vanilloid cation channel, GPCRs, estrogen receptors, neuromodulators of SON and PVN functions and aquaporin 2 from molecular mechanisms to behavioral responses. Genetic approaches help us to discriminate axonal versus dendritic process and to separate the release of VP and OT from astrocytes, intra-MCNs, to axons, extra-MCNs, in the control of several behaviors as drinking and eating behavior, defensive-aggressive behavior, and maternal behavior.
    No preview · Article · Dec 2013 · Pharmacology Biochemistry and Behavior
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    ABSTRACT: In many cases, it is difficult or even impossible to distinguish parathyroid lesions from thyroid ones at ultrasound as well as at scintiscan and even at cytology, because they often share common features. The aim of this study was to evaluate the role of Parathyroid Hormone (PTH) determination in the aspirates in the differential diagnosis of parathyroid from thyroid lesions in an area of mild iodine deficiency and high prevalence of thyroid nodules. Forty-six consecutive patients were suspected to have one or more nodule(s) of parathyroid origin because of their position in the posterior aspect of thyroid lobes and/or their shape and echo-pattern at ultrasound examination. In 13 cases, there were also laboratory findings suggestive for primary hyperparathyroidism, with clinical evidence in 6 of these patients. A total of 55 lesions suspected to be of parathyroid origin were selected. After obtaining cytological preparations, the needle used to perform the fine-needle aspirate (FNA) was washed using 1 ml of normal saline. Intact PTH determination in the washout was done whereas the evaluation was performed directly in the aspirated fluid in case of cystic lesions. The values of PTH in the aspirates ranged from 6.7 to 16640 pg/ml. Sixteen patients underwent surgical intervention and the histological examination of the 23 operated lesions previously submitted to FNA-PTH showed 11 parathyroid adenomas, 5 hyperplasic parathyroid lesions and 7 benign thyroid nodules. A strong positive correlation between high levels of PTH in the aspirate and the histological findings of parathyroid lesions was found. A value over 245 pg/ml was constantly associated to the parathyroid lesions. Our results confirmed the high accuracy of FNA-PTH determination in differentiating parathyroid lesions from thyroid nodules and this is of special value in an area of mild iodine deficiency with a high prevalence of thyroid nodules.
    No preview · Article · Dec 2013
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    ABSTRACT: The clinical occurrence of ectopic thyroid gland is an infrequently encountered condition, resulting from the developmental abnormality during the migration of the thyroid anlage from the floor of the primitive foregut to its final position in the neck. It can be found along the way of thyroid descent, in the midline, or laterally in the neck or even in the mediastinum or under the diaphragm. This condition is often asymptomatic, whereas symptoms could be related to ectopic thyroid size, to its relationships with surrounding organs or to diseases affecting the ectopic thyroid in the same way they involve orthotopic glands. Sometimes, a growing mass can lead to the clinical suspicion of a tumor disease. On the other hand, thyroid ectopy must be distinguished from metastasis of thyroid cancer. Scintigraphy and ultrasonography are the main diagnostic means for evaluating ectopic thyroid tissue, whereas fine needle aspiration could be useful in the presence of a nodular ectopic gland or when the coexistence of an orthotopic thyroid can arise the suspicion of a metastasis from a thyroid cancer. Surgical removal is indicated in symptomatic cases, whereas radioiodine ablation is reserved to recurrent disease. In this paper we report an emblematic case of ectopic thyroid gland and a review of the literature dealing with this condition.
    No preview · Article · Oct 2013
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    ABSTRACT: In this review, we analyzed the anatomical and functional role played by central and peripheral chemoreceptors (CHRs), as well as the relationship between CHR activation and vasopressin (AVP) release. The most important site of central chemoreception has been localized at level of the rostral ventrolateral medulla (RVLM) in the retrotrapezoid nucleus (RTN, even if several brain areas partecipate in chemoreception mechanisms as nucleus tractus solitarius (NTS), ventrolateral nucleus (A1) and locus coeruleus (A6), brainstem raphe nuclei (B7-B8-B9), pre-Botzinger complex, fastigial nucleus (FN), and the hypothalamus. Functionally, these central CHRs are able to detect very small pH/CO2 fluctuations, and play a role on brain blood flow, acid-base balance, blood pressure via sympathetic tone and arousal. They receive, also, synaptic inputs from 5-HTergic raphe nuclei and NAergic A1 and A6 cell group, as well as are regulated by ATP released from astrocytes via activation of P2X and P2Y purinergic receptors, activation of protein kinase C, gene transcription and sustained increase of Ca++. Afferent nerve fibers from carotid CHRs reach the CNS via the glossopharyngeal and vagus nerve. They transduce low arterial O2 tension into increased action potential activity, which causes bradycardia and coronary vasodilatation via vagal stimulation and systemic vasoconstriction via catecholaminergic stimulation. Electrophysiological studies showed the existence of two renal CHRs. R1 CHRs do not have a resting discharge but are activated by renal ischemia and hypotension. R2 CHRs have a resting discharge and respond to backflow of urine into the renal pelvis. Stimulation of carotid CHRs, induced by bilateral carotid occlusion, increases AVP release. This response is blocked by lesions of the septal forebrain nuclei, medial preoptic area and anterior hypothalamus. A high proportion of A1 and A6 NAergic neurons receive peripheral CHR inputs that play an excitatory role on AVPergic neurons of SON and PVN. Indeed, we showed that microinjection of the presynaptic alpha2-adrenergic agonist clonidine into the NTS blocked AVP release induced by hypovolemia and this effect was prevented by the alpha2-adrenoceptor blocker yohimbine. Cardiovascular responses, as heart rate and blood pressure, induced by peripheral CHRs activation are mediated by NMDA receptors in the RVLM and stiumulate AVP release. Axons arising from 5-HTergic B7-B8-B9 raphe nuclei synapse in the RTN and play a stimulatory role on AVP release. Hypoxic-hypoxia increases neurohypophyseal blood flow and AVP release, an effect inhibited by CHR denervation. Decreases in arterial pH and increases in arterial pCO2 stimulate AVP release. The peripheral vasodilaltation induced by warm with a decrease in central blood volume stimulates AVP release via CHR mechanism. Activation of R1 and R2 CHRs, following increased intrapelvic pressure with solutions of mannitol, NaCl and KCl produces a significant increase of AVP secretion. Intrarenal infusion of bradykinin, which excites afferent renal nerves, increases the activity of AVPergic neurones in the SON, an effect inhibited by renal denervation. Electrical stimulation of renal afferent nerves increases the activity of AVPergic neurons in the PVN, thus showing that signals arising from renal CHRs modulate the activity of hypothalamic AVPergic neurons. Therefore, it is interesting to underline that the central neural pathways subserving osmotic and non-osmotic control of AVP secretion are correlated to brain areas partecipating to chemoreception mechanisms.
    Full-text · Article · Sep 2013 · Endocrine Metabolic & Immune Disorders - Drug Targets(Formerly Current Drug Targets - Immune Endocrine & Metabolic Disorders)
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    ABSTRACT: In this review, we analyzed the role played by central and peripheral chemoreceptors (CHRs) in vasopressin (AVP) secretion control. Central neural pathways subserving osmotic and non-osmotic control of AVP secretion are strictly correlated to brain areas participating in chemoreception mechanisms. Among the different brain areas involved in central chemoreception, the most important site has been localized in the retrotrapezoid nucleus of the rostral ventrolateral medulla. These central CHRs are able to detect very small pH/CO2 fluctuations, participating in brain blood flow regulation, acid-base balance and blood pressure control. Decreases in arterial pH and increases in arterial pCO2 stimulate AVP release by the Supraoptic and Paraventricular Nuclei. Carotid CHRs transduce low arterial O2 tension into increased action potential activity, leading to bradycardia and coronary vasodilatation via vagal stimulation, and systemic vasoconstriction via catecholaminergic stimulation. Stimulation of carotid CHRs by hypoxia increases neurohypophyseal blood flow and AVP release, an effect inhibited by CHRs denervation. Two renal CHRs have been identified: Type R1 CHRs do not have a resting discharge but are activated by renal ischemia and hypotension; Type R2 CHRs have a resting discharge and respond to backflow of urine into the renal pelvis. Signals arising from renal CHRs modulate the activity of hypothalamic AVPergic neurons: activation of R1 and R2 CHRs, following increased intrapelvic pressure with solutions of mannitol, NaCl and KCl, produces a significant increase of AVP secretion and the same effect has been obtained by the intrarenal infusion of bradykinin, which excites afferent renal nerves, as well as by the electrical stimulation of these nerves.
    No preview · Article · Sep 2013

  • No preview · Article · Mar 2013