Epidural Anesthesia Retards Intestinal Acidosis and Reduces Portal Vein Endotoxin Concentrations during Progressive Hypoxia in Rabbits

Background: Because it is postulated that gut is important via bacterial translocation in the development of the systemic inflammatory response and multiple organ dysfunction, the preservation of gut integrity is a therapeutic goal for physicians who care for critically ill patients. The aim of the current study was to evaluate whether epidural anesthesia prevented gut injury and subsequent translocation of endotoxin during acute progressive hypoxia in rabbits.

Methods: After the placement of an epidural catheter, 18 male rabbits, anesthetized with buprenorphine-midazolam, were allocated randomly to two groups: 0.5% lidocaine (group E) and saline (group C) groups. The solutions (0.4 ml/kg) were injected epidurally, followed by continuous infusion (0.1 ml[middle dot]kg-1[middle dot]h-1) during the study period. Portal blood flow, portal endotoxin concentrations, and intramucosal pH (pHi) of the ileum were measured at baseline and during two stages of progressive hypoxia (fraction of inspired oxygen [Fio2] = 0.15 and 0.10).

Results: In both study groups, the portal blood flow was preserved to a similar extent during acute hypoxia. However, pHi was reduced to a lesser extent in group E (7.33 +/- 0.12 versus 7.22 +/- 0.12 at an Fio2 of 0.15 and 7.13 +/- 0.15 versus 7.03 +/- 0.12 at an Fio2 of 0.10; mean +/- SD, P < 0.01), concurrently with lower portal endotoxin concentrations (P < 0.05) compared with group C.     

Role of xanthine oxidase in delayed lipid peroxidation in rat liver induced by acute exhausting exercise

The aim of this study was to examine whether xanthine oxidase (XOD)-derived hepatic oxidative damage occurs in the main not during but following strenuous exercise. The degree of damage to hepatic tissue catalyzed by XOD was investigated immediately and 3?h after a single bout of exhausting exercise, in allopurinol and saline injected female Wistar rats. Allopurinol treatment resulted in increased hypoxanthine and decreased uric acid contents in the liver compared with the saline treated group, immediately and 3?h after the exercise. Analysis immediately after the exercise showed no changes in hepatic hypoxanthine, uric acid, and thiobarbituric acid-reactive substance (TBARS) contents in the saline treated group, when compared with the resting controls. However, significant increases in uric acid contents in the saline treated livers were observed 3?h after the exercise, relative to the controls. Hepatic TBARS content in the saline treated group were markedly greater than those in both the control and allopurinol treated groups after 3?h of recovery following the exercise. It was concluded that a single bout of exhausting exercise may impose XOD-derived hepatic oxidative damage, primarily during the recovery phase after acute severe exercise.     

A complex muscle fiber network in the cricothyroid muscle: a scanning electron microscopic study

OBJECTIVES: To examine the three-dimensional ultrastructure of cricothyroid (CT) muscle fibers to elucidate their morphologic characteristics with regard to the specific functions of the muscle. STUDY DESIGN: An anatomic animal study. METHODS: The CT muscles of five adult rats were processed using the HCl-hydrolysis method to remove the peri- and intramuscular connective tissue components. The fine muscle fiber arrangements were observed by scanning electron microscopy. RESULTS: Complex muscle fiber interconnections (myomyous junctions) were identified in the muscles. Myomyous junctions were characterized by the connection of many villous processes that were 1 to 2 mum in diameter and 2 to 4 mum in length with a serrated appearance at the ends of a lateral branch or a bifurcating trunk of the muscle fibers. CONCLUSIONS: Myomyous junctions form a complex muscle fiber network, which is thought to synchronize the activity of the CT muscle fibers. This is the first three-dimensional demonstration of the muscle fiber network in the CT muscle; this network may play a major role in the functional specificity of the CT muscle.     

Pharmacokinetic Analysis of in Vivo Metabolism of Amino Acid or Dipeptide Conjugates of Salicylic Acid in Rabbit Intestinal Microorganisms

We analyzed the pharmacokinetics of salicylic acid (SA)–amino acid (alanine, glutamic acid, methionine, and tyrosine) or SA–dipeptide (glycylglycine) conjugates in rabbits, by using a model that takes into account the metabolism of prodrug to SA by intestinal microorganisms and, also, by model-independent analysis. The blood concentration profiles of these prodrugs and released SA following intracecal and oral administration to rabbits were obtained previously (Nakamura et al., J. Pharm. Pharmacol., 44, 295–299, 1992; Chem. Pharm. Bull., 40, 2164–2168, 1992; Int. J. Pharm., 87, 59–66, 1992; J. Pharm. Pharmacol., 44, 713–716, 1992). First, the overall in vivo behavior was evaluated by statistical moment analysis. Next, the blood concentration profiles of prodrug and SA following intracecal and oral administration were simultaneously fitted to the above model. In general, good agreement was observed between fitted lines and experimental data for every prodrug, suggesting the validity of this model. The obtained parameters characterized the difference in the rate of metabolism and absorption among the prodrugs. Lower absorbability and enhanced hydrolysis rate of the prodrug lead to prolonged blood concentration of SA.     

Venous reconstruction by endvenectomy with temporary arteriovenous fistula for stasis syndrome of lower extremity: Experimental and clinical studies

Effect of the temporary arteriovenous fistula on venous reconstruction for stasis syndrome of the lower extremity was studied experimentally and clinically. The canine iliac vein was replaced with an autogenous vein graft in which the intimal surface was roughened by scrubbing with sponge. A temporary arteriovenous fistula which was closed surgically three or four weeks later was created between the femoral vessels. The patency rate for twenty-one grafts was 80.9 per cent for one to thirty-six weeks (mean 8 weeks), in contrast to complete failure in the control group in which no arteriovenous fistula was created. Adequate healing of the luminal surface of the grafts were experimentally demonstrated by light microscopic examination and en face silver staining of the endothel-like cells with the aid of patent arteriovenous fistula for three weeks. This procedure was clinically applied in four patients with stasis syndrome of the lowere extremities. Good function of the reconstructed venous segments in three of four patients was observed for the last 3 to 8 years after the operations. A looping technique using 2-0 monfilament nylon around the fistula devised by us was very helpful to make easy the shunt closure later. Open endvenecoomy with a temporary arteriovenous fistula is believed to be an acceptable approach for segmental chronic occlusive lesion in the iliac vein.     

Corrigendum to ‘Antinociceptive effects of the selective non-peptide δ-opioid receptor agonist TAN-67 in diabetic mice’ [Eur. J. Pharmacol. 276 (1995) 131–135]

The antinociceptive potencies of 2-methyl-4a-(3-hydroxyphenyl)-1,2,3,4,4a,5,12,12a-octahydro-quinolino[2,3,3-g]isoquinoline (TAN-67), a non-peptidic δ-opioid receptor agonist, were examined using the acetic acid abdominal constriction test and the tail-flick test in diabetic mice. TAN-67, at doses of 3–100 mg/kg, i.p., produced a marked and dose-dependent inhibition of the number of acetic acid-induced abdominal constrictions in both non-diabetic and diabetic mice. The antinociceptive effect of TAN-67 in the acetic acid abdominal constriction test in diabetic mice was greater than that in non-diabetic mice. Indeed, the ED₅₀ (95% confidence limits) value of TAN-67 for the inhibition of acetic acid-induced abdominal constrictions in diabetic mice (6.0 (3.5–10.5) mg/kg) was significantly lower than that in non-diabetic mice (31.4 (14.2–69.4) mg/kg). The antinociceptive effect of TAN-67 was not antagonized by pretreatment with either β-funaltrexamine, a selective μ-opioid receptor antagonist, or nor-binaltorphimine, a selective κ-opioid receptor antagonist. When 7-benzylidenenaltrexone (0.3 mg/kg, s.c.), a selective δ₁-opioid receptor antagonist, was administered 10 min before treatment with TAN-67, the antinociceptive effect of TAN-67 was significantly antagonized. However, naltriben, a selective δ₂-opioid receptor antagonist, had no significant effect on the antinociceptive effect of TAN-67. Furthermore, in the tail-flick test, TAN-67 at doses of 3–30 mg/kg, i.p., also produced a marked and dose-dependent antinociceptive effect in diabetic mice, but not in non-diabetic mice. In conclusion, TAN-67 produced an antinociceptive effect through the activation of δ₁-opioid receptors. Furthermore, the results of this study support our hypothesis that mice with diabetes are selectively hyperresponsive to δ₁-opioid receptor-mediated antinociception.     

Corrigendum to ‘Antinociceptive effects of the selective non-peptide δ-opioid receptor agonist TAN-67 in diabetic mice’ [Eur. J. Pharmacol. 276 (1995) 131–135]

The antinociceptive potencies of 2-methyl-4aα-(3-hydroxyphenyl)-1,2,3,4,4a,5,12,12aα-octahydro-quinolino[2,3,3-g]isoquinoline (TAN-67), a non-peptidic δ-opioid receptor agonist, were examined using the acetic acid abdominal constriction test and the tail-flick test in diabetic mice. TAN-67, at doses of 3–100 mg/kg, i.p., produced a marked and dose-dependent inhibition of the number of acetic acid-induced abdominal constrictions in both non-diabetic and diabetic mice. The antinociceptive effect of TAN-67 in the acetic acid abdominal constriction test in diabetic mice was greater than that in non-diabetic mice. Indeed, the ED₅₀ (95% confidence limits) value of TAN-67 for the inhibition of acetic acid-induced abdominal constrictions in diabetic mice (6.0 (3.5–10.5) mg/kg) was significantly lower than that in non-diabetic mice (31.4 (14.2–69.4) mg/kg). The antinociceptive effect of TAN-67 was not antagonized by pretreatment with either β-funaltrexamine, a selective μ-opioid receptor antagonist, or nor-binaltorphimine, a selective κ-opioid receptor antagonist. When 7-benzylidenenaltrexone (0.3 mg/kg, s.c.), a selective δ₁-opioid receptor antagonist, was administered 10 min before treatment with TAN-67, the antinociceptive effect of TAN-67 was significantly antagonized. However, naltriben, a selective δ₂-opioid receptor antagonist, had no significant effect on the antinociceptive effect of TAN-67. Furthermore, in the tail-flick test, TAN-67 at doses of 3–30 mg/kg, i.p., also produced a marked and dose-dependent antinociceptive effect in diabetic mice, but not in non-diabetic mice. In conclusion, TAN-67 produced an antinociceptive effect through the activation of δ₁-opioid receptors. Furthermore, the results of this study support our hypothesis that mice with diabetes are selectively hyperresponsive to δ₁-opioid receptor-mediated antinociception.     

Cartilaginous nevus on the glabella

Cartilaginous nevus usually occurs in front of the auricle as an accessory auricle and much less frequently on the cheek or anterior part of the neck. We report a case of cartilaginous nevus found on an unusual location, The glabella of the face, in an otherwise normal newborn girl. We think that it was a remnant of the branchial cartilage derived from the first pharyngeal arch of embryonic life.