Objective To investigate the role of H1 and H2 receptors in the locus ceruleus （LC） in carotid sinus baroreceptor reflex （CSR） resetting induced by intracerebroventricular （i.c.v.） injection of histamine （HA）....Objective To investigate the role of H1 and H2 receptors in the locus ceruleus （LC） in carotid sinus baroreceptor reflex （CSR） resetting induced by intracerebroventricular （i.c.v.） injection of histamine （HA）. Methods The left and right carotid sinus regions were isolated from the systemic circulation in 18 male Sprague-Dawley rats anesthetized with pentobarbital sodium. The intracarotid sinus pressure （ISP） was altered in a stepwise manner in vivo. ISP-mean arterial pressure （MAP） relationship curve and its characteristic parameters were constructed by fitting to the logistic function with five parameters. The changes in CSR performance induced by i.c.v. HA and the effects of pretreatment with H1 or H2 receptors selective antagonist, chlorpheniramine （CHL） or cimetidine （CIM） into the LC, on the responses of CSR to HA were examined. Results I.c.v. HA （100 ng in 5 μl） significantly shifted the ISP-MAP relationship curve upwards （P 〈 0.05） and obviously decreased the value of the reflex parameters such as MAP range and maximum gain （P 〈 0.05）, but increased the threshold pressure, saturation pressure and ISP at maximum gain （P 〈 0.05）. The pretreatment with CHL （0.5 μg in 1 μl） or CIM （1.5 μg in 1 μl） into the LC could obviously attenuate the changes mentioned above in CSR performance induced by HA, but the alleviative effect of CIM was less remarkable than that of CHL （P 〈 0.05）. Respective microinjection of CHL or CIM alone into the LC with the corresponding dose and volume did not change CSR performance significantly （P 〉 0.05）. Conclusion Intracerebroventricular administration of HA results in a rapid resetting of CSR and a decrease in reflex sensitivity, and the responses of CSR to HA may be mediated, at least in part, by H1 and H2 receptors activities in the LC, especially by H1 receptors. Moreover, the effects of the central HA on CSR might be related to a histaminergic descending pathway from the hypothalamus to LC.展开更多
This report describes color doppler imaging (CDI) in theevaluation and follow-up of nine patients with carotid cavernous sinusfistulas.The orbits and carotid arteries were examined with CDI.In allcases,the diagnosis w...This report describes color doppler imaging (CDI) in theevaluation and follow-up of nine patients with carotid cavernous sinusfistulas.The orbits and carotid arteries were examined with CDI.In allcases,the diagnosis was confirmed by angiography.CDI clearlydemonstrated the dilated superior ophthalmic veins (SOVs) with retrogradeflow and low resistance arterial doppler waveform in all nine patients (10eyes).After the study of quantitative hemodynamics,we found that directcarotid cavernous sinus fistulas s...展开更多
Objective Introduction When we perform transvenous embolization of carotid cavernous fistula, we selectively occluded the venous outflow to the retrograde cortical venous drainage and retrograde ophthalmic venous drai...Objective Introduction When we perform transvenous embolization of carotid cavernous fistula, we selectively occluded the venous outflow to the retrograde cortical venous drainage and retrograde ophthalmic venous drainage as the initial steps before the rest of the cavernous sinus. The rationale is to prevent re-diversion of flow into the ophthalmic veins and cortical veins in a subtotally occluded carotid cavernous fistula.Method From 1997 to 2004, a total of 46 patients with carotid cavernous fistula were treated by transvenous embolization using the proposed selective occlusion strategy. There were 6 direct and 40 dural cartoid cavernous fistulae. The embolic agents were Guglielmi detachable coils and fibered platinum coils. Transvenous embolization routes included inferior petrosal sinus (IPS) alone (32 patients), IPS and intercavernous sinus (9 patients), and superior ophthalmic vein (5 patients).Result The follow-up period ranged from 4 months to 7 years. One patient developed retinal hemorrhage due to ophthalic vein thrombosis one week after the embolization procedure. Two patients had transient ophthalmoplegia and 2 patients had symptomatic recurrence of the carotid cavernous fistula during the follow-up. Clinical cure was achieved in 44 patients (96%).Conclusion The sequential occlusion strategy offers a safe and effective method in the transvenous embolization of carotid cavernous fistula.展开更多
Objective To discuss the approach and technique of the direct microsurgery of intracavemous sinus carotid artery aneurysms (ICCAAns). Methods All the 15 cases of ICCAAns underwent the direct microsurgery via the carot...Objective To discuss the approach and technique of the direct microsurgery of intracavemous sinus carotid artery aneurysms (ICCAAns). Methods All the 15 cases of ICCAAns underwent the direct microsurgery via the carotid artery-cavernous sinus space approach. Results Immediate carotid arteriography after the surgery showed that the aneurysms disappeared and the carotid artery could be showed clearly and normall. In a follow up period ranged frcm 1 months to 9 years,it was showed that,among 5 cases with 333,IV,V a,VI nerve paralysis before the surgery, three completely recovered,one recovered incompletely. All patients regained the capability of undertaking mormal cativities. None experienced rebleeding or neuroparalysis. Conclusion Direct microsurgery via this is approach is an ideal treatment of ICCAAns. 6 refs.展开更多
Violence against the neck can result in a range of macromorphological and micromorphological findings.However,the forensic relevance of the carotid sinus in cases of violence against the neck remains controversial.In ...Violence against the neck can result in a range of macromorphological and micromorphological findings.However,the forensic relevance of the carotid sinus in cases of violence against the neck remains controversial.In this follow-up study of 22 cases of suicidal and accidental strangulations,carotid bifurcations were examined histologically for morphological changes implying direct trauma,including haemorrhage and immunohistochemical expression of heat-shock proteins 27,60,and 70 and aquaporin-3.These cases were compared with a control group(82 cases)without neck compression or head trauma and with variable causes of death.No relevant histopathological findings implying direct trauma of the carotid bifurcation were found.No cases showed positive aquaporin-3 staining and only five cases showed positive heat-shock protein-27 staining,all of which were hangings.Without massive trauma of the carotid bifurcation,histological alterations cannot be expected.Without signs of rapid death,findings of acute circulatory failure,macromorphological and micromorphological findings of neck compression,and reliable markers indicating relevant impact on the carotid bifurcation the diagnosis of a lethal reflex cannot be verified.展开更多
Objective To determine whether prostaglandin E2 (PGE2) influences the dog skeletal muscle circulation by a direct action on the vascular smooth muscle or via pre- or post-synaptic modulation of sympathetic neurotransm...Objective To determine whether prostaglandin E2 (PGE2) influences the dog skeletal muscle circulation by a direct action on the vascular smooth muscle or via pre- or post-synaptic modulation of sympathetic neurotransmission.Methods In 18 anaesthetised dogs, a gracilis muscle was vascularly isolated and perfused at constant flow. Sympathetic vasoconstrictor tone on the muscles was reflexly controlled by alterations to the pressure at which the isolated carotid sinuses were perfused. The effects of PGE2 injection into the muscle were compared at low carotid sinus pressure, high carotid sinus pressure, and following denervation of the muscle, with or without noradrenaline infusion.Results At all levels of sympathetic tone, PGE2 produced significantly more vasodilation than the saline vehicle. However, at a carotid sinus pressure of 46.0±2.3 mmHg (1 mmHg=0.133 kPa), PGE2 caused a decrease in femoral arterial perfusion pressure of 52.6±7.1 mmHg, which was significantly greater than the response at a carotid sinus pressure of 208.5±3.7 (33.6±4.2 mmHg decrease) or following denervation (25.6±3.7 mmHg decrease). In a separate group of denervated muscles, PGE2 caused a similar decrease in perfusion pressure in the presence or absence of a noradrenaline infusion.Conclusions PGE2 appears to cause vasodilation through two separate mechanisms: one mechanism involves presynaptic inhibition of sympathetic vasoconstrictor tone, whilst the other is independent of the sympathetic nervous system, and is therefore presumably a direct action on the vascular smooth muscle or endothelium. Under our experimental conditions, both mechanisms contributed equally to the vasodilation.展开更多
文摘Objective To investigate the role of H1 and H2 receptors in the locus ceruleus （LC） in carotid sinus baroreceptor reflex （CSR） resetting induced by intracerebroventricular （i.c.v.） injection of histamine （HA）. Methods The left and right carotid sinus regions were isolated from the systemic circulation in 18 male Sprague-Dawley rats anesthetized with pentobarbital sodium. The intracarotid sinus pressure （ISP） was altered in a stepwise manner in vivo. ISP-mean arterial pressure （MAP） relationship curve and its characteristic parameters were constructed by fitting to the logistic function with five parameters. The changes in CSR performance induced by i.c.v. HA and the effects of pretreatment with H1 or H2 receptors selective antagonist, chlorpheniramine （CHL） or cimetidine （CIM） into the LC, on the responses of CSR to HA were examined. Results I.c.v. HA （100 ng in 5 μl） significantly shifted the ISP-MAP relationship curve upwards （P 〈 0.05） and obviously decreased the value of the reflex parameters such as MAP range and maximum gain （P 〈 0.05）, but increased the threshold pressure, saturation pressure and ISP at maximum gain （P 〈 0.05）. The pretreatment with CHL （0.5 μg in 1 μl） or CIM （1.5 μg in 1 μl） into the LC could obviously attenuate the changes mentioned above in CSR performance induced by HA, but the alleviative effect of CIM was less remarkable than that of CHL （P 〈 0.05）. Respective microinjection of CHL or CIM alone into the LC with the corresponding dose and volume did not change CSR performance significantly （P 〉 0.05）. Conclusion Intracerebroventricular administration of HA results in a rapid resetting of CSR and a decrease in reflex sensitivity, and the responses of CSR to HA may be mediated, at least in part, by H1 and H2 receptors activities in the LC, especially by H1 receptors. Moreover, the effects of the central HA on CSR might be related to a histaminergic descending pathway from the hypothalamus to LC.
文摘This report describes color doppler imaging (CDI) in theevaluation and follow-up of nine patients with carotid cavernous sinusfistulas.The orbits and carotid arteries were examined with CDI.In allcases,the diagnosis was confirmed by angiography.CDI clearlydemonstrated the dilated superior ophthalmic veins (SOVs) with retrogradeflow and low resistance arterial doppler waveform in all nine patients (10eyes).After the study of quantitative hemodynamics,we found that directcarotid cavernous sinus fistulas s...
文摘Objective Introduction When we perform transvenous embolization of carotid cavernous fistula, we selectively occluded the venous outflow to the retrograde cortical venous drainage and retrograde ophthalmic venous drainage as the initial steps before the rest of the cavernous sinus. The rationale is to prevent re-diversion of flow into the ophthalmic veins and cortical veins in a subtotally occluded carotid cavernous fistula.Method From 1997 to 2004, a total of 46 patients with carotid cavernous fistula were treated by transvenous embolization using the proposed selective occlusion strategy. There were 6 direct and 40 dural cartoid cavernous fistulae. The embolic agents were Guglielmi detachable coils and fibered platinum coils. Transvenous embolization routes included inferior petrosal sinus (IPS) alone (32 patients), IPS and intercavernous sinus (9 patients), and superior ophthalmic vein (5 patients).Result The follow-up period ranged from 4 months to 7 years. One patient developed retinal hemorrhage due to ophthalic vein thrombosis one week after the embolization procedure. Two patients had transient ophthalmoplegia and 2 patients had symptomatic recurrence of the carotid cavernous fistula during the follow-up. Clinical cure was achieved in 44 patients (96%).Conclusion The sequential occlusion strategy offers a safe and effective method in the transvenous embolization of carotid cavernous fistula.
文摘Objective To discuss the approach and technique of the direct microsurgery of intracavemous sinus carotid artery aneurysms (ICCAAns). Methods All the 15 cases of ICCAAns underwent the direct microsurgery via the carotid artery-cavernous sinus space approach. Results Immediate carotid arteriography after the surgery showed that the aneurysms disappeared and the carotid artery could be showed clearly and normall. In a follow up period ranged frcm 1 months to 9 years,it was showed that,among 5 cases with 333,IV,V a,VI nerve paralysis before the surgery, three completely recovered,one recovered incompletely. All patients regained the capability of undertaking mormal cativities. None experienced rebleeding or neuroparalysis. Conclusion Direct microsurgery via this is approach is an ideal treatment of ICCAAns. 6 refs.
文摘Violence against the neck can result in a range of macromorphological and micromorphological findings.However,the forensic relevance of the carotid sinus in cases of violence against the neck remains controversial.In this follow-up study of 22 cases of suicidal and accidental strangulations,carotid bifurcations were examined histologically for morphological changes implying direct trauma,including haemorrhage and immunohistochemical expression of heat-shock proteins 27,60,and 70 and aquaporin-3.These cases were compared with a control group(82 cases)without neck compression or head trauma and with variable causes of death.No relevant histopathological findings implying direct trauma of the carotid bifurcation were found.No cases showed positive aquaporin-3 staining and only five cases showed positive heat-shock protein-27 staining,all of which were hangings.Without massive trauma of the carotid bifurcation,histological alterations cannot be expected.Without signs of rapid death,findings of acute circulatory failure,macromorphological and micromorphological findings of neck compression,and reliable markers indicating relevant impact on the carotid bifurcation the diagnosis of a lethal reflex cannot be verified.
文摘Objective To determine whether prostaglandin E2 (PGE2) influences the dog skeletal muscle circulation by a direct action on the vascular smooth muscle or via pre- or post-synaptic modulation of sympathetic neurotransmission.Methods In 18 anaesthetised dogs, a gracilis muscle was vascularly isolated and perfused at constant flow. Sympathetic vasoconstrictor tone on the muscles was reflexly controlled by alterations to the pressure at which the isolated carotid sinuses were perfused. The effects of PGE2 injection into the muscle were compared at low carotid sinus pressure, high carotid sinus pressure, and following denervation of the muscle, with or without noradrenaline infusion.Results At all levels of sympathetic tone, PGE2 produced significantly more vasodilation than the saline vehicle. However, at a carotid sinus pressure of 46.0±2.3 mmHg (1 mmHg=0.133 kPa), PGE2 caused a decrease in femoral arterial perfusion pressure of 52.6±7.1 mmHg, which was significantly greater than the response at a carotid sinus pressure of 208.5±3.7 (33.6±4.2 mmHg decrease) or following denervation (25.6±3.7 mmHg decrease). In a separate group of denervated muscles, PGE2 caused a similar decrease in perfusion pressure in the presence or absence of a noradrenaline infusion.Conclusions PGE2 appears to cause vasodilation through two separate mechanisms: one mechanism involves presynaptic inhibition of sympathetic vasoconstrictor tone, whilst the other is independent of the sympathetic nervous system, and is therefore presumably a direct action on the vascular smooth muscle or endothelium. Under our experimental conditions, both mechanisms contributed equally to the vasodilation.
