International Union of Pharmacology. XLI. Compendium of voltage-gated ion channels: potassium channels

This summary article presents an overview of the molecular relationships among the voltage-gated potassium channels and a standard nomenclature for them, which is derived from the IUPHAR Compendium of Voltage-Gated Ion Channels. The complete Compendium, including data tables for each member of the potassium channel family can be found at http://www.iuphar-db.org/iuphar-ic/.     

The intestinal anti-inflammatory effect of minocycline in experimental colitis involves both its immunomodulatory and antimicrobial properties

Some antibiotics, including minocycline, have recently been reported to display immunomodulatory properties in addition to their antimicrobial activity. The use of a compound with both immunomodulatory and antibacterial properties could be very interesting in the treatment of inflammatory bowel disease (IBD), so the aim of our study was to evaluate the anti-inflammatory effect of minocycline in several experimental models of IBD. Firstly, the immunomodulatory activity of the antibiotic was tested in vitro using Caco-2 intestinal epithelial cells and RAW 264.7 macrophages; minocycline was able to inhibit IL-8 and nitrite production, respectively. In vivo studies were performed in trinitrobenzenesulfonic acid (TNBS)-induced rat colitis and dextran sodium sulfate (DSS)-induced mouse colitis. The results revealed that minocycline exerted an intestinal anti-inflammatory effect when administered as a curative treatment in the TNBS model, modulating both immune and microbiological parameters, being confirmed in the DSS model; whereas none of the other antibiotics tested (tetracycline and metronidazole) showed anti-inflammatory effect. However, minocycline administration before the colitis induction was not able to prevent the development of the intestinal inflammation, thus showing that only its antimicrobial activity is not enough for the anti-inflammatory effect. In conclusion, minocycline displays an anti-inflammatory effect on different models of rodent colitis which could be attributed to the association of its antibacterial and immunomodulatory properties.     

Molecular cloning of a glibenclamide-sensitive, voltage-gated potassium channel expressed in rabbit kidney.

Shaker genes encode voltage-gated potassium channels (Kv). We have shown previously that genes from Shaker subfamilies Kv1.1, 1.2, 1.4 are expressed in rabbit kidney. Recent functional and molecular evidence indicate that the predominant potassium conductance of the kidney medullary cell line GRB-PAP1 is composed of Shaker-like potassium channels. We now report the molecular cloning and functional expression of a new Shaker-related voltage-gated potassium channel, rabKv1.3, that is expressed in rabbit brain and kidney medulla. The protein, predicted to be 513 amino acids long, is most closely related to the Kv1.3 family although it differs significantly from other members of that family at the amino terminus. In Xenopus oocytes, rabKv1.3 cRNA expresses a voltage activated K current with kinetic characteristics similar to other members of the Kv1.3 family. However, unlike previously described Shaker channels, it is sensitive to glibenclamide and its single channel conductance saturates. This is the first report of the functional expression of a voltage-gated K channel clone expressed in kidney. We conclude that rabKv1.3 is a novel member of the Shaker superfamily that may play an important role in renal potassium transport.     

Is endovascular revascularisation worthwhile in diabetic patients with critical limb ischemia who also have end-stage renal disease?

To present the outcomes of endovascular treatment of diabetics patients with critical limb ischemia who have end-stage renal disease. Limb-salvage was achieved in 58.6% of the limbs during a mean follow-up period of 12.4 months. No major amputations were required on patients with rest pain or with grade 1 lesions.     

The rise in methamphetamine use among American Indians in Los Angeles County

A preliminary review of substance abuse treatment admission data from 2001-2005 was conducted to explore the use of methamphetamine among American Indians in treatment programs funded by Los Angeles County. Comparisons were made between primary methamphetamine users and users whose primary drug was a substance other than methamphetamine. In that period, the number of American Indians reporting methamphetamine as their primary drug in Los Angeles County significantly increased, particularly among females.     

The arginine-deiminase enzymatic system on gingivitis: preliminary pediatric study

AIM.: The lactic bacteria are Gram-positive microorganisms with coccus or stick shape, which share a number of physiological and biochemical properties. Several experimental evidences suggest the possibility of using lactic acid bacterial as a preventive or therapeutic potential approaches, alternative or complementary to prevention or treatment protocols currently followed in several pathological conditions. Lactobacillus brevis is able, through the arginine-deiminase activity, to subtract the substrate (arginine) to nitric oxide synthase, and to inhibit in vitro generation of nitric oxide from rat's peritoneal macrophages. These data led us to study the in vivo L. brevis anti-inflammatory effect choosing as experimental model the gingivitis. MATERIALS AND METHODS.: In our study were examined 21 subjects, 16 males and 5 females, aged between 5 and 12 years, with marginal gingivitis problems who have been given chewing gum containing the principle to test in measure of three per day. RESULTS.: At the time T1, after treatment, 18 patients no longer showed inflammation; 2 of them had a slight inflammation and only 1 patient still showed a moderate inflammation. CONCLUSIONS.: From our research, as confirmed by clinical and laboratory investigation, results an effective anti-inflammatory action of arginine-deiminase system that some bacteria possessing.     

Carotid atheromatosis in nondiabetic renal transplant recipients: the role of prediabetic glucose homeostasis alterations

BACKGROUND: Prediabetic glucose homeostasis alterations are important cardiovascular risk factors but their role in renal transplant recipients (RTR) has not been established. METHODS: In 172 RTRs without pretransplant or de novo diabetes, we measured carotid intima media thickness (c-IMT) and performed an oral glucose tolerance test (OGTT). RESULTS: In multivariate analysis, age, hypertension and male sex were independently associated with a c-IMT in the third tertile. A significant interaction between gender and glucose homeostasis parameters was observed. Among male RTR, those with a c-IMT in the third tertile showed significantly higher plasma glucose and HbA1c levels (5+/-0.5% vs. 5.1+/-0.5% vs. 5.5+/-0.4%; P<0.01 tertile 3 vs. 2 or 1) than those in other tertiles. Insulin action parameters were not significantly different. The odds ratio of being in the higher c-IMT tertile was 2.9 (95% CI: 1.05-8.1) per each 1% increase of HbA1c. By contrast, glucose and HbA1c levels were not significantly different between c-IMT tertiles in female RTR. However, age-adjusted insulin levels after OGTT were higher (86+/-10 vs. 51.7+/-9.4; P=0.02) and the insulin sensitivity index lower (0.8+/-0.3 vs. 0.048+/-0.03; P=0.04) among females in the third tertile as compared to the first one. CONCLUSION: Prediabetic glucose homeostasis alterations in RTRs are related to carotid atherosclerosis, although there may be gender differences in the underlying alteration.