Vascular segments in the human spleen. (1/255)

Corrosion casts of human splenic arterial trees revealed the presence of two segments-a superior, and an inferior - in 84% of cases and three segments - a superior, a middle and an inferior - in 16% of cases. These segments are separated by avascular planes.  (+info)

Effects of imipramine, an uptake inhibitor, on double-peaked constrictor responses to periarterial nerve stimulation in isolated, perfused canine splenic arteries. (2/255)

Using a cannula insertion method, periarterial nerve electrical stimulations were performed at 1 and 10 Hz in the isolated, perfused canine splenic artery. Electrical nerve stimulation readily caused double-peaked vasoconstrictions. The 1st-peak response at 1 Hz was not influenced by treatment with imipramine but the 2nd one was significantly enhanced by it. The 2nd-peak response was markedly blocked by prazosin. An additional treatment with alpha,beta-methylene ATP, a P2X-purinoceptor desensitizer, abolished electrical stimulation-induced vascular responses that remained. At 10 Hz, the responses to electrical stimulation were not significantly influenced by imipramine. On the other hand, the imipramine treatment inhibited the tyramine-induced vasoconstriction but potentiated the noradrenaline-induced one. ATP-induced responses were not modified by imipramine. From these results, it is concluded that 1) the 1st-peaked constriction is mainly due to a P2X-purinoceptor-dependent mechanism, 2) the 2nd one is mainly due to an alpha1-adrenoceptor-dependent mechanism, and 3) presynaptic uptake mechanisms may perform an important role in the regulation of vascular reactivity, especially at a low frequency.  (+info)

Post-traumatic pancreatitis with associated aneurysm of the splenic artery: report of 2 cases and review of the literature. (3/255)

In patients with acute pancreatitis, profuse gastrointestinal bleeding is associated with a high death rate. The cause of such bleeding must be evaluated and the bleeding controlled urgently. Aneurysm formation is usually the cause of the bleeding. Angiography is needed to make a definitive diagnosis and the bleeding site should be controlled by angiographic embolization if possible. If this fails, aneurysm resection is necessary. Two patients are described. Both had aneurysms of the splenic artery, presenting as massive gastrointestinal bleeding in one patient and bleeding into an associated pseudocyst in the other. They required surgical repair, which was successful in both cases.  (+info)

Effects of prolonged cold storage on double peaked vasoconstrictor responses to periarterial nerve stimulation in isolated canine splenic arteries. (4/255)

1. P2X-Purinoceptors and alpha1-adrenoceptors have previously been shown to involve in the double peaked vasoconstrictor responses to periarterial electrical nerve stimulation in the isolated and perfused canine splenic artery. The present study made an attempt to investigate effects of prolonged cold storage (7 days at 4 degrees C) on vasoconstrictor responses to periarterial electrical nerve stimulation, tyramine, noradrenaline and adenosine 5'-triphosphate (ATP) in the isolated canine splenic artery. 2. The periarterial nerve stimulation (1-10 Hz) readily causes a double peaked vasoconstriction in the non-stored preparations. After cold stored for 7 days, the double peaked vasoconstriction was still recognized, although the response became significantly smaller. The first phase was decreased relatively greater than the second phase by the cold storage. 3. In the cold stored preparations, the dose-response curve for tyramine was shifted to the right in a parallel manner. Prazosin almost completely inhibited tyramine-induced vasoconstriction but alpha,beta-methylene ATP failed to influence the response to tyramine. 4. The vasoconstrictor responses to noradrenaline and ATP were not significantly modified by the prolonged cold storage. 5. From these results, it is concluded that the functions of sympathetic co-transmission of purinergic components might be influenced more than that of adrenergic components in the cold storage canine splenic artery.  (+info)

Splenic artery aneurysms: methods of laparoscopic repair. (5/255)

PURPOSE: Surgical therapy for splenic artery aneurysms (SAAs) has traditionally consisted of a laparotomy with resection of the aneurysm and possibly a splenectomy. Our early experience with the laparoscopic approach to treat SAAs is reported. METHODS: A retrospective review of medical records was conducted on all patients who underwent laparoscopic resection of SAAs at the Cleveland Clinic Foundation from May 1996 to August 1997. RESULTS: Four patients with SAAs, three women and one man, with an average age of 55 years (range, 37 to 63 years), underwent successful laparoscopic SAA repair. The average size of the aneurysm was 3.2 cm (range, 2.5 to 5.0 cm). Three patients underwent an aneurysm resection, whereas one patient underwent simple ligation. Intraoperative ultrasound scanning with Doppler was used in three cases as a means of localizing the aneurysm and identifying all feeding vessels; the complete cessation of flow within the aneurysm in the case in which the feeding vessels were simply ligated was also documented. The average intraoperative time was 150 minutes (range, 100 to 190 minutes). The mean estimated blood loss was 105 mL (range, 20 to 300 mL). There were no intraoperative complications. The average hospital stay was 2.2 days (range, 1 to 4 days). CONCLUSION: The laparoscopic approach to splenic artery aneurysm by aneurysmectomy or splenic artery ligation can be safe and effective. The laparoscopic approach affords a short hospital stay and an effective result.  (+info)

Intractable oesophageal variceal bleeding caused by splenic arteriovenous fistula: treatment by transcatheter arterial embolization. (6/255)

We describe a rare case of splenic arteriovenous fistula and venous aneurysm which developed after splenectomy in a 40-year-old woman who presented with epigastralgia, watery diarrhoea, repeated haematemesis and melaena caused by hyperkinetic status of the portal system and bleeding of oesophageal varices. It was diagnosed by computed tomography and angiography, and obliterated with giant Gianturco steel coils.  (+info)

Extrasplenic pseudoaneurysm. The role of color flow Doppler ultrasound in diagnosis. (7/255)

Pseudoaneurysm of the splenic artery has been rarely reported and the Doppler echocardiographic finding seldom described. Herein we report a rare case of huge extrasplenic pseudoaneurysm, which was detected by color flow Doppler ultrasonography and successfully treated by ligation of the splenic artery and resection of the pseudoaneurysm.  (+info)

An unusual Ca(2+) entry pathway activated by protein kinase C in dog splenic artery. (8/255)

The characteristics of the Ca(2+) entry pathways that are activated by protein kinase C (PKC) in canine splenic artery were investigated. Phorbol 12, 13-dibutyrate (PDB) contracted tissues and increased Ca(2+) influx. PDB-induced contraction was reduced by preincubation of tissues in Ca(2+)-free Krebs' solution (1 mM EGTA) but was unaffected when Ca(2+)-free solution was applied after contraction was initiated with PDB. In contrast, (45)Ca influx and contraction induced by PDB were resistant to nifedipine, Cd(2+), Gd(3+), La(3+), or Ni(2+) whether added before or during exposure to PDB. Indeed, Cd(2+) reduced (45)Ca(2+) efflux and potentiated Ca(2+) influx, but not PDB-induced contraction. Norepinephrine (NE)-induced contractions were inhibited by preincubation in Ca(2+)-free Krebs' solution (1 mM EGTA). Nifedipine (10 microM) led to a small reduction in the NE-induced contraction but was without effect on (45)Ca(2+) influx. Pretreatment for 16 min with Cd(2+), Gd(3+), or La(3+) (each 1 mM) reduced or abolished NE-induced contraction and Ca(2+) influx. Application of these cations after exposure to NE did not affect (45)Ca(2+) influx but reduced tension. The Q(10) for the increase in (45)Ca(2+) influx was approximately 2 for high K(+) and NE, but 4 for PDB. The results suggest that stimulation of PKC in dog splenic artery activates a Ca(2+) entry pathway that is resistant to di- and trivalent cations. The inhibition of Ca(2+) influx by preincubating with cations during short-term exposure to NE may represent an action on Ca(2+) turnover that precedes activation of PKC.  (+info)