cAMP-Epac1 signaling is activated in DDAVP-induced endolymphatic hydrops of guinea pigs

Abstract Objective To explore whether Cyclic Adenosine Monophosphate (cAMP)-Epac1 signaling is activated in 1-Desamino-8-D-arginine-Vasopressin-induced Endolymphatic Hydrops (DDAVP-induced EH) and to provide new insight for further in-depth study of DDAVP-induced EH. Methods Eighteen healthy, red-eyed guinea pigs (36 ears) weighing 200-350 g were randomly divided into three groups: the control group, which received intraperitoneal injection of sterile saline (same volume as that in the other two groups) for 7 consecutive days; the DDAVP-7d group, which received intraperitoneal injection of 10 mg/mL/kg DDAVP for 7 consecutive days; and the DDAVP-14d group, which received intraperitoneal injection of 10 μg/mL/kg DDAVP for 14 consecutive days. After successful modeling, all animals were sacrificed, and cochlea tissues were collected to detect the mRNA and protein expression of the exchange protein directly activated by cAMP-1 and 2 (Epac1, Epac2), and Repressor Activator Protein-1 (Rap1) by Reverse Transcription (RT)-PCR and western blotting, respectively. Results Compared to the control group, the relative mRNA expression of Epac1, Epac2, Rap1A, and Rap1B in the cochlea tissue of the DDAVP-7d group was significantly higher (p< 0.05), while no significant difference in Rap1 GTPase activating protein (Rap1gap) mRNA expression was found between the two groups. The relative mRNA expression of Epac1, Rap1A, Rap1B, and Rap1gap in the cochlea tissue of the DDAVP-14d group was significantly higher than that of the control group (p< 0.05), while no significant difference in Epac2 mRNA expression was found between the DDAVP-14d and control groups. Comparison between the DDAVP-14d and DDAVP-7d groups showed that the DDAVP-14d group had significantly lower Epac2 and Rap1A (p< 0.05) and higher Rap1gap (p < 0.05) mRNA expression in the cochlea tissue than that of the DDAVP-7d group, while no significant differences in Epac1 and Rap1B mRNA expression were found between the two groups. Western blotting showed that Epac1 protein expression in the cochlea tissue was the highest in the DDAVP-14d group, followed by that in the DDAVP-7d group, and was the lowest in the control group, showing significant differences between groups (p< 0.05); Rap1 protein expression in the cochlea tissue was the highest in the DDAVP-7d group, followed by the DDAVP-14d group, and was the lowest in the control group, showing significant differences between groups (p< 0.05); no significant differences in Epac2 protein expression in the cochlea tissue were found among the three groups. Conclusion DDAVP upregulated Epac1 protein expression in the guinea pig cochlea, leading to activation of the inner ear cAMP-Epac1 signaling pathway. This may be an important mechanism by which DDAVP regulates endolymphatic metabolism to induce EH and affect inner ear function. Oxford Centre for Evidence-Based Medicine 2011 Levels of Evidence Level 5.

Desmopressin acetate use in von Willebrand's disease: a survey on current practices in Brazil

ABSTRACT Introduction: von Willebrand's disease (VWD) is the most common inherited bleeding disorder. The 1-desamino-8-d-arginine vasopressin (DDAVP) is the treatment of choice for most responsive patients with VWD. The aim of this study was to evaluate DDAVP use in the management of VWD. Method: We implemented a survey targeting medical doctors involved in the management of VWD in Brazil. Data was collected during a national congress on Hematology in November 2017. Main results: A total of 51/80 (63.8%) questionnaires were collected. Most participants (76.2%) were hematologists who assisted adult patients and approximately 60% worked at hemophilia treatment centers (HTCs). Approximately half of participants who reported treating patients with VWD, assisted on average, less than 5 patients per month, and approximately 60% declared not having used any DDAVP for treating VWD in the previous year. However, most participants (70%) prescribed FVIII-containing VWF concentrate (VWF/FVIII) for 1-10 patients in the previous year. More than 80% of the participants recognized the main indications for DDAVP. Physicians who recognized indication for DDAVP for type 1 VWD more often had prescribed DDAVP in previous year (p = 0.03). Barriers for prescribing DDAVP varied and included unavailability of laboratory facilities and consumables for DDAVP testing and lack of skills on its prescription. Conclusion: The DDAVP is currently underused in Brazil, as opposed to the excessive use of VWF/FVIII in VWD patients. We suggest the adoption of measures targeting educational and auditing programs. Furthermore, availability of laboratory reagents is needed to evaluate response and increment the correct use of DDAVP.

Effect of Zhenwu Tang on regulating of "AVP-V2R-AQP2" pathway in NRK-52E cells / 中国中药杂志

This study was aimed to investigate the effect and mechanism of Zhenwu Tang on AVP-V2R-AQP2 pathway in NRK-52E cells . Forty eight male SD rats were randomly divided into eight groups with 6 animals in each group. Distilled water or 22.68 g·kg⁻¹·d⁻¹ Zhenwu Tang(calculated by raw drug dosage meter) was given by gavage. Blood samples were collected by cardiac puncture， and the medicated serum was centrifuged from the blood by 3 000 r·min⁻¹. NRK-52E cells were treated with different medicated serum or dDAVP. The condition of cell proliferation was detected by RTCA. The distribution of V2R and AQP2 in cells were detected by immunofluorescence. The expression of V2R， PKA and AQP2 were detected by Western blot and AQP2 mRNA level was detected by real-time PCR. Results showed that the level of AQP2 mRNA(<0.01) and protein expression of V2R， PKA and AQP2(<0.05， <0.01， <0.05) of Z7d group which was treated with Zhenwu Tang medicated serum for 24 h were significantly higher than that of normal rat serum group. And the expression level of V2R， p-AQP2 and AQP2(<0.01， <0.05， <0.01) of Z7d+dDAVP group were significantly increased comparing to normal rat serum group. The results indicate that the applying of Zhenwu Tang medicated serum could increase the expression level of V2R， PKA and AQP2 which exist in AVP-V2R-AQP2 pathway in NRK-52E， and there is synergistic effect between Zhenwu Tang medicated serum and dDAVP. So the pathway of AVP-V2R-AQP2 may be one of the mechanism for which Zhenwu Tang regulate balance of water transportation.

Enurese noturna na infância / Nocturnal enuresis in children

A enurese noturna é definida como micção involuntária durante o sono, pelo menos duas vezes por semana, em crianças sem anomalias congênitas ou adquiridas do trato urinário ou sistema nervoso, em idade que o controle esfincteriano habitualmente está presente. O principal objetivo deste trabalho é abordar os mais diversos tipos de tratamento da enurese, classificada como primária ou secundária, quanto à evolução e, em relação aos sintomas, como monossintomática (simples) e polissintomática. O tratamento deve ser individualizado e com a fundamental coparticipação dos familiares, sendo que a motivação da criança é fundamental para seu sucesso. A literatura médica, em sua maioria, recomenda o início do tratamento a partir dos seis anos, pois a essa altura já pode interferir nas relações sociais infantis.A terapia farmacológica, principalmente com desmopressina (DDAVP) e anticolinérgicos, para a enurese noturna é apresentada no trabalho. O alarme urinário, para a Sociedade Internacional de Continência, parece ser o tratamento mais eficaz, atingindo até 79% de sucesso.

Central diabetic insipidus associated with suspected pituitary gland tumor in a dog / 대한수의학회지

A 12-year-old spayed female Yorkshire terrier dog was presented with two-weeks history of lethargy, mental dullness and polydipsia. Neurologic examination revealed proprioceptive defect of all limbs and loss of swallowing gag reflex. The dog revealed persistent dehydration, hypernatremia, hyperosmolarity and hyposthenuria. On magnetic resornance imaging (MRI), the mass were heterogeneous signality on T1 weighted images, hyperintense signality on T2 weighted image with contrast enhancement on hypothalamohypophyseal lesion. Based on these findings, the dog was suspected as having pituitary gland tumor. Through water deprivation test and response to desmopressin acetate (1-deamino-8-D-arginine, DDAVP), this case was diagnosed by central diabetes insipidus (CDI). This paper reports the clinical sign, MRI, response to the exogenous antidiuretic hormone of CDI due to suspected pituitary tumor in a dog and DDAVP administration was evaluated effective therapy to correct hypernatremia induced by CDI.

Criteria of cure and remission in Cushing's disease: an update: [review]

We review the clinical and biochemical criteria used for evaluation of the transsphenoidal pituitary surgery results in the treatment of Cushing's disease (CD). Firstly, we discuss the pathophysiology of the hypothalamic-pituitary-adrenal axis in normal subjects and patients with CD. Considering the series published in the last 25 years, we observed a significant variation in the remission or cure criteria, including the choice of biochemical tests, timing, threshold values to define remission, and the interference of glucocorticoid replacement or previous treatment. In this context we emphasize serum cortisol levels obtained early (from hours to 12 days) in the postoperative period without any glucocorticoid replacement or treatment. Our experience demonstrates that: (i) early cortisol < 5 to 7 µg/dl, (ii) a period of glucocorticoid dependence > 6 mo, (iii) absence of response of cortisol/ACTH to CRH or DDAVP, (iv) return of dexamethasone suppression, and circadian rhythm of cortisol are appropriate indices of remission of CD. In patients with undetectable cortisol levels early after surgery, recurrence seems to be low. Finally, although certain biochemical patterns are more suggestive of remission or surgical failure, none has been proven to be completely accurate, with recurrence observed in approximately 10 to 15 percent of the patients in long-term follow-up. We recommended that patients with CD should have long-term monitoring of the CRH-ACTH-cortisol axis and associated co-morbidities, especially hypopituitarism, diabetes mellitus, hypertension, cardiovascular disturbances, and osteoporosis.

Neste artigo, são revisados os principais critérios clínicos e hormonais utilizados para avaliação do tratamento cirúrgico da Doença de Cushing (DC). Inicialmente são comentados aspectos fisiopatológicos que orientam a avaliação hormonal e os principais fatores clínicos, laboratoriais, cirúrgicos e histológicos associados com melhores resultados, observados nas principais séries da literatura e em pacientes acompanhados prospectivamente pelos autores. Foram revisados, também, critérios adotados nas principais séries da literatura, nos últimos 25 anos, chamando-se atenção para as dosagens hormonais, o momento em que foram realizadas, a possibilidade de interferência de tratamentos prévios e da reposição glicocorticóide. À seguir, essas dosagens são discutidas salientando-se a importância do cortisol obtido seqüencialmente no pós-operatório e sem a interferência de reposição glicocorticóide. A experiência prospectiva dos autores, recentemente referendada na literatura, demonstra que valores de cortisol < 5 a 7 µg/dl associados com um período de dependência aos glicocorticóides > 6 meses, ausência de resposta do ACTH/cortisol ao DDAVP e/ou CRH, retorno da supressão à dexametasona e do ritmo circadiano, estão associados com remissão da DC. Em pacientes com cortisol indetectável após cirurgia transesfenoidal, a chance de recidiva parece ser menor do que naqueles em que se observa cortisol detectável. Finalmente, chamamos a atenção para que, mesmo adotando critérios rígidos de avaliação, a recidiva da DC pode ocorrer a longo prazo em até 15 por cento dos casos, recomendando-se, portanto, que esses pacientes sejam acompanhados por tempo indeterminado, com monitorização cuidadosa do eixo CRH-ACTH-cortisol e de suas co-morbidades, especialmente hipopituitarismo, diabete melito, hipertensão arterial, alterações cardiovasculares e osteoporose.

The Expression of Aquaporin-2,3,4 in Rats' Endolymphatic Sac and Kidney / 听力学及言语疾病杂志

Objective To confirm the expression of Aquaporin2,3,4(AQP2,3,4,water channel protein) in rats'endolymphatic sacs(ES)and kidneys and to investigate and to compare the effects of anti-diuretic hormone(AVP) and DDAVP([deamino-Cys1,D-Arg8]-Vasopressin,V2-receptor agonist)on the expression of AQP2 in rats' ESs and kidneys.Methods 30 healthy Swards white rats were divided into the negative control,AVP group and dDAVP group respectively.The animals were cardiacally perfused.The temporal bones and kidneys were taken out and sectioned by means of the paraffin-embedded technique.The sections of ESs were labeled with fluorescent antibody by immunohistochemical method,and the kidneys' with avidin-biotin-peroxidase complex method(ABC).The expressions of AQP-2 were confirmed in the ESs of the rats while the different effects of the AVP and DDAVP on the ESs and the kidneys were observed.The slides used were analyzed by the image-analyzer and the subsequent data were statistically studied.Results In the cytomembrane and cytoplasm of ESs' epithelia,the constant and clear fluorescent reaction could be observed in the normal control group with the first antibody of AQP2.Significant feeble fluorescent reaction of the first antibody of AQP-2 was revealed in AVP group and DDAVP group.In comparison with the control group,significant stain was found in AVP group and DDAVP group.Noted were also lower gray(P