Different impacts of α- and β-blockers in neurogenic hypertension produced by brainstem lesions in rat.

نویسندگان

  • Wen-Hsien Lu
  • Kai-Sheng Hsieh
  • Pei-Jung Lu
  • Yi-Shan Wu
  • Wen-Yu Ho
  • Pei-Wen Cheng
  • Chi-Cheng Lai
  • Michael Hsiao
  • Ching-Jiunn Tseng
چکیده

BACKGROUND Bilateral lesions of nucleus tractus solitarii in rat result in acute hypertension, pulmonary edema, and death within hours. The hypertension results from excessive catecholamine release. Catecholamine can activate connexin43 to regulate cell death. There is no study investigating the cardiopulmonary impacts of different adrenergic blockers and apoptosis mechanism in rat model. METHODS The authors microinjected 6-hydroxydopamine into nucleus tractus solitarii of the rat (n = 8 per group) and evaluated the cardiopulmonary changes after treatment with different concentrations of α1-blockers, α2-blockers, β-blockers, and α-agonists. RESULTS In the rat model, the authors found that prazosin (0.15 mg/kg) treatment could preserve cardiac output and reverse neutrophil infiltrations in lungs and lead to prevent pulmonary hemorrhagic edema. The time-dependent increases in connexin43 and terminal deoxynucleotidyl transferase dUTP nick end labeling-positive cells induced by 6-hydroxydopamine lesions were decreased after prazosin treatment (terminal deoxynucleotidyl transferase dUTP nick end labeling-positive cells at 6 h: 64.01 ± 2.41% vs. 24.47 ± 3.10%; mean ± SD, P < 0.001, in heart, and 80.83 ± 2.52% vs. 2.60 ± 1.03%, P < 0.001, in lung). However, propranolol caused further compromise of the already impaired cardiac output with consequence of rapid death. Phenylephrine enhanced the phenotype in the link between connexin43 expressions and terminal deoxynucleotidyl transferase dUTP nick end labeling-positive cells but not yohimbine. Connexin43 expressions and terminal deoxynucleotidyl transferase dUTP nick end labeling-positive cells were more decreased with prazosin (0.15 and 0.3 mg/kg) than that with prazosin (0.05 mg/kg) treatment. CONCLUSIONS α1-Receptors are the keystones of the phenotype. In some brainstem encephalitis and brain injury with nucleus tractus solitarii involvement, early α1-receptor blockade treatment may prevent acute death from tissue apoptosis. α-Blockers can also decrease cerebral perfusion pressure, and further studies are needed in translation to brain injury with increased intracranial pressure.

برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید

ثبت نام

اگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید

منابع مشابه

Neonatal Hypertension: Etiology, Diagnosis and Management

Neonatal hypertension is a rare and complex condition, with an incidence rate of 0.2% to 3%. It can be resulted by several risk factors such as renal diseases, use of several drugs, neurologic, cardiac, respiratory and endocrine causes. Gestational age, birth weight and conceptual age are the most important risk factors. Renal diseases can be found in about 25% to 50% of hypertension at neonata...

متن کامل

The vasodilatory action of telmisartan on isolated mesenteric artery rings from rats

Objective(s): Angiotensin Ⅱ type 1 receptor blockers (ARBs) represent one of the widely used antihypertensive agents. In addition to anti-hypertension effect, some ARBs also show other molecular effects such as activating peroxisome proliferator-activated receptor-γ and so on. Here we studied the effects of telmisartan on the rat isolated mesenteric artery rings pre-contracted by phenylephrine ...

متن کامل

Antihypertensive effects of some new nitroxyalkyl 1,4-dihydropyridine derivatives in rat model of two-kidney, one-clip hypertension

Dihydropyridine calcium channel blockers consist one of the widely-used groups of drugs for the management of hypertension. In this study, antihypertensive effects of 5 newly synthesized derivatives of DHP was examined the in rat model of two-kidney, one-clip renal hypertension. The results showed that those compounds containing two nitroxy groups had less decreasing effect on MAP (Men Arterial...

متن کامل

SUPPRESSION OF VLDL-TRIACYLGLYCEROL SECRETION B Y BOTH α AND β-ADRENOCEPTOR AGONISTS IN ISOLATED RAT HEPATOCYTES

The effects of alpha and beta-adrenergic stimulation on triacylglycerol secretion were investigated in isolated rat hepatocytes. Epinephrine within 3h of incubation suppressed triacylglycerol secretion by 35% and increased its cellular content by 18%. The inhibitory effect of epinephrine was abolished by inclusion of phentolamine and also prazosin but not with propranolol. Trifluoperazine c...

متن کامل

Acute fulminating neurogenic hypertension produced by brainstem lesions in the rat.

Bilateral electrolytic lesions of the nucleus tractus solitarii in the rat at the level of the obex abolished baroreceptor reflexes and resulted in an immediate, marked elevation in systemic blood pressure without a change in heart rate. In unanesthetized rats the hypertension was associated with a marked increase in total peripheral resistance, a reduction in blood flow in the abdominal aorta,...

متن کامل

ذخیره در منابع من


  با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید

برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید

ثبت نام

اگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید

عنوان ژورنال:
  • Anesthesiology

دوره 120 5  شماره 

صفحات  -

تاریخ انتشار 2014