Changes of vasoactive polypeptides during postoperative hypertensive crisis in patients with hypertensive intracerebral hemorrhage

Background Hypertensive crisis could be found after operation in patients with hypertensive intracerebral hemorrhage （HICH）. The aim of this study was to explore the changes and th; roles of some vasoactive polypeptides during postoperative hypertensive crisis in patients with HICH. Methods A total of 31 patients, who were admitted for craniotomy, were enrolled into this study. After the operation, the patients were divided into three groups. Group I consisted of 9 patients with postoperative hypertensive crisis, and group Ⅱ was composed of 13 patients without postoperative hypertensive crisis. Nine patients, who denied history of hypertension or HICH, were set as group Ⅲ. The levels of some vasoactivators in the three groups were measured before and after the operation. The differences in the results among the groups were analyzed using the ANOVA. The data collected before and after the operation in the group Ⅰ was compared by Wilcoxon test. Results The concentration of endothelin in group Ⅰ was significantly higher than that in group Ⅲ （P〈0.05）. The level of thromboxane A2 and the ratio of thromboxane B2 to 6-keto-PGF1α in group Ⅰ were significantly higher than those in the other two groups （P〈0.05）. In group Ⅰ, the levels of plasma renin activity, angiotensin Ⅱ, aldosterone, catecholamine, and endothelin before the operation were significantly higher than those determined after the operation （P〉0.05）. Conclusions Postoperative hypertensive crisis may be due to the increased thromboxane A2 and relatively inadequate prostacyclin, especially 6-keto-PGF1α. The increased level of endothelin and intraoperative stimulation also play a certain role in the development of postoperative hypertensive crisis.

Effects of psychological stress on small intestinal motility and expression of cholecystokinin and vasoactive intestinal polypeptide in plasma and small intestine in mice

AIM: To investigate the effects of psychological stress on small intestinal motility and expression of cholecystokinin (CCK) and vasoactive intestinal polypeptide (VIP) in plasma and small intestine, and to explore the relationship between small intestinal motor disorders and gastrointestinal hormones under psychological stress. METHODS: Thirty-six mice were randomly divided into psychological stress group and control group. A mouse model with psychological stress was established by housing the mice with a hungry cat in separate layers of a two-layer cage. A semi-solid colored marker (carbon-ink) was used for monitoring small intestinal transit. CCK and VIP levels in plasma and small intestine in mice were measured by radioimmunoassay (RIA). RESULTS: Small intestinal transit was inhibited (52.18±19.15% vs70.19±17.79%, P<0.01) in mice after psychological stress, compared to the controls. Small intestinal CCK levels in psychological stress mice were significantly lower than those in the control group (0.75±0.53 μg/g vs1.98±1.17 μg/g, P<0.01), whereas plasma CCK concentrations were not different between the groups. VIP levels in small intestine were significantly higher in psychological stress mice than those in the control group (8.45±1.09 μg/g vs7.03±2.36 μg/g, P<0.01), while there was no significant difference in plasma VIP levels between the two groups. CONCLUSION: Psychological stress inhibits the small intestinal transit, probably by down-regulating CCK and up-regulating VIP expression in small intestine.

Effect of fluoxetine on depression-induced changes in the expression of vasoactive intestinal polypeptide and corticotrophin releasing factor in rat duodenum

AIM: To investigate changes in vasoactive intestinal polypeptide (VIP) and corticotrophin releasing factor (CRF) in the plasma and duodenum of chronic stress- induced depressed rats and the effects of fluoxetine hydrochloride (fluoxetine) treatment on depression- induced changes in VIP and CRF. METHODS: A Sprague-Dawley rat model of chronic stress-induced depression was produced. Thirty experimental rats were randomly divided into the following groups: control group, saline-treated depressed group, and fluoxetine-treated depressed group. Open- f ield testing was performed to assess the rats’ behavior. VIP and CRF levels in plasma were measured by ELISA. Immunofluorescence techniques combined with laser scanning confocal microscopy (LSCM) were used to investigate VIP and CRF expression in the duodenum. RESULTS: The open-field behavior, both crossing and rearing, of depression model rats, decreased signif icantly compared with those of normal control rats over 5 min. Defecation times increased significantly. Compared to the control group, FITC fluorescence of duodenal CRF expression and plasma CRF levels in the depressed rats increased significantly (fluorescence intensity of duodenal CRF: 11.82 ± 2.54 vs 25.17 ± 4.63; plasma CRF: 11.82 ± 2.54 ng/L vs 25.17 ± 4.63 ng/L, P < 0.01), whereas duodenal VIP expression and plasma VIP levels decreased signif icantly (fluorescence intensity of duodenal VIP: 67.37 ± 18.90 vs 44.51 ± 16.37; plasmaVIP: 67.37 ± 18.90 ng/L vs 44.51 ± 16.37 ng/L, P < 0.01). Fluoxetine improved depressed behavior, increased VIP expression and decreased CRF expression in plasma and the duodenal tissue of depressed rats. CONCLUSION: Chronic stress can induce injury to the duodenum, accompanied by increasing CRF and decreasing VIP in the plasma and duodenum. Treatment with fluoxetine can ameliorate pathological changes in the duodenum of depressed rats, which suggests that antidepressants are an effective therapeutic agent for some duodenal diseases caused by chronic stress. VIP is a potential therapeutic strategy.

Study on vasoactive intestinal polypeptide receptor 1 gene translation in psoriatic epidermis with the topical treatment of capsaicin ointment

Objective To investigate the mechanism of capsaicin in treating active psoriasis vulgaris.Methods A total of 42 patients with active psoriasis vulgaris diagnosed by histology and clinical features were given either placebo or 0.025% capsaicin ointment four times daily for 30 days randomly by double-blind method.Vasoactive intestinal polypeptide receptor 1(VIPR1)gene translation in active psoriatic lesions before and after treatment with capsaicin ointment was detected by in situ hybridization.Results There was positive staining of VIPR1 gene in all the layers of psoriatic epidermis(95.5%)before the treatment with capsaicin ointment,but nearly no dyeing in epidermis(18.2%)after the treatment for 30 days.There was nearly no brown staining before and after treatment in control group.Conclusion VIPR1 gene translation in psoriatic epidermis is down-regulated after capsaicin treatment for 30 days.

VASOACTIVE INTESTINAL POLYPEPTIDE PREVENTS INJURY OF PULMONARY VASCULAR PERMEABILITY DUE TO XANTHINE WITH XANTHINE OXIDASE

Hyperpermeability is a crux of pathogenesis of sudden lung edema in many pulmonary disorders. especially in acute lung injury and adult respiratory distress syndrome(ARDS). Using our modified method for assessment of pulmonary vascular permeability. we observed the effects of xanthine with xanthine oxidase(X-XO) perfused in rat pulmonary artery and the protection of vasoactive intestinal polypeptide(VIP) against the injury of pulmonary vascular permeabilrty. After addition of xanthine oxidase in the perfusate reservoir containing xanthine￣(125) I-albumin leak index (￣(125)IALI)was remarkably increased while peak airway pressure(Paw) was not significantly increased, and perfusion pressure of pulmonary artery(Ppa)and lung wet/dry weight ratio(W/D) were only slightly increased. Xanthine plus xanthine oxidase also increased thromboxane B_2(TX B_2) and 6-keto-prostaglandin F_(1α)(6-keto -PGF_(1α)) in the perfusate. Treatment with VIP obviously reduced or totally prevented all signs of injury. Simultaneously, VIP also diminished or abolished the associated generation of arachidonate products. The results indicated that VIP has potent protective activity against injury of pulmonary vascular permeability and may be a physiological modulator of inflammatory damage to vascular endothelium associated with toxic oxygen metacolites.

Distribution of Vasoative Intestinal Polypeptide in CranialParasym pathetic Ganglion of the Rat

Immunoreactivity (IR) for vasoactive intestinal polypeptide (VIP) of cranial parasympathetic ganglia of the rat was observed with indirect immunofluorescent method. It was found that there were VIP IR principal neurons in the ciliary, pterygopalatine, and otic ganglia. The highest positive ratio of VIP IR cells was located in the ciliary ganglia (34.8%), followed by that in the pterygopalatine ganglia(17.0%), and the lowest was found in the otic ganglia (15.4%). VIP IR small intensely fluorescent (SIF) cells and nerve fibers were not observed. Distributive characteristics of neuropeptides and functional significance of VIP in cranial parasympathetic ganglia were discussed.

RELAXANT EFFECTS OF VASOACTIVE INTESTINAL PEPTIDE ON PULMONARY ARTERY IN CHRONICALLY HYPOXIC RATS

The object of this study is to investigate the effect of VIP on pulmonary artery of chronically hypoxic rats. It was shown that chronic hypoxia depressed significantly pulmonary artery relaxation induced by VIP as compared with those of control (P<0. 001). The vascular relaxation of both groups was correlated with concentration of VIP. In addition, the relaxant effect of VIP on pulmonary arteries in rats was endothelium─independent, and was not prevented by indomethacin or nordihydroguaiaretic acid, but was abolished completely by methylene blue. These results suggest that the lower relaxation of pulmonary artery in rats might not be due to the endothelial injury caused by chronic hypoxia, and chronic hypoxia may inhibit directly the soluble guanylate cyclase in vascular smooth muscle cells invloved in synthesis of cGMP and thus reduced the sensitivity and reactivity of pulmonary artery to VIP.