The kinetic disposition of ethanol was studied in neonatal lambs. The mean plasma clearance rate was 36 mg/l/h, 17% of that in near-term pregnant sheep. Activity increased slowly during the first 5 days of life. Hepatic alcohol dehydrogenase activity in the neonatal lamb was only 7% of that in adult sheep, but was similar to activity in the near-term fetus. Placental enzyme activity was even lower than that in the fetus and neonate, suggesting only a minor role for it in the metabolic disposition of ethanol during pregnancy. The pH optimum for alcohol dehydrogenase was higher in the fetus and neonate (9.6) than in maternal liver or placenta (9.0). The pharmacodynamic consequences of prolonged neonatal exposure to ethanol due to impaired metabolism remain to be explored.
We asked whether the anesthetic requirement (MAC) of fetal lambs is lower than that of pregnant ewes. In five pregnant ewes anesthetized with a subarachnoid block, a fetal foot was withdrawn through a hysterotomy. The ewe then breathed 1.5% halothane and a clamp was applied to the fetal foot at 2-min intervals. We concomitantly obtained arterial blood from previously implanted catheters. When fetal movement in response to clamping the foot ceased, halothane was discontinued and the stimulus and sampling continued until the fetus began to move. Anesthesia was again resumed and continued until movement stopped. Anesthesia was then deepened and MAC was determined in the mother (stimulus--ear clamp). The fetal blood concentrations of halothane at MAC were 48 +/- 28 mg/L; they were 133 +/- 5 mg/L in the mother. This difference was highly significant (P less than 0.001). Calculated end-tidal concentrations were 0.33% and 0.69%, respectively. In two animals delivered by cesarean section, MAC increased progressively over the first 12 h of life. Progesterone levels concomitantly decreased.
We simultaneously measured intracellular pH (pHi) and isometric tension in canine basilar arteries. pHi was calculated from the ratio of fluorescence intensities at 540 nm of exciting wavelengths of 500 and 440 nm in the presence of 2',7'-bis(carboxyethyl)-5(6)-carboxyfluorescein (BCECF). pHi was 7.33 +/- 0.02 in Krebs-Henseleit solution (pH of 7.4 at 37 degrees C). Application of the anion exchange blocker 4-acetamido-4'-isothiocyanostilbene-2,2'-disulfonic acid (SITS) decreased the resting pHi by 0.25 pH units. Increasing extracellular pH (pHo) [by decreasing CO2 tension (PCO2)] from 7.4 to 7.8 increased pHi by 0.38 pH units and increased tension by 2.28 +/- 0.21 mN. Decreasing pHo from 7.8 to 7.4 (by increasing PCO2) restored the pHi and muscle tension to their baseline levels. SITS inhibited the increase in pHi and isometric tension in response to the increase in pHo in an endothelium-independent fashion. The Na+/H+ exchange blockers, amiloride or 5-(N-methyl-N-guanidinocarbonylmethyl)-amiloride, did not affect the pHo or tension changes. The results suggest that in the range of pH tested, anion exchange is more important than Na+/H+ exchange in the regulation of pHi and mechanical tone in the basilar artery.
We investigated the haemodynamic alterations in 2‐day old anaesthetized piglets after acute ethanol intoxication using the microsphere technique. After ethanol infusion, mean arterial blood pressure (MABP) decreased by 6%, cardiac output (CO) decreased by 26%, heart rate (HR) increased by 20% and systemic vascular resistance (SVR) increased by 36%. Arterial perfusion to the kidneys, gastrointestinal (GI) organs and carcass decreased by 39%, 34% and 26%, respectively. In piglets pretreated with 4‐methylpyrazole (4‐MP), an alcohol dehydrogenase inhibitor, the decrease in MABP and increase in HR were not observed after ethanol infusion, but the reduction in CO and increase in SVR were maintained. Arterial blood flow to the GI organs and carcass, but not the kidneys, remained at significantly reduced levels. These observations indicate that ethanol can adversely affect CO and arterial perfusion to GI and musculoskeletal structures while metabolites of ethanol, such as acetaldehyde, affect MABP and HR. Therefore, the clinical effects observed after acute ethanol intoxication in neonates may vary with their rate of ethanol metabolism.
A high-pressure liquid chromatographic technique has been used to measure the amount of monocaffeoyl-, mono-p-coumaroyl-, and monoferuloyl-tartaric acids in grapes. The amount of each hydroxycinnamic acidtartaric acid ester has been quantitated on both a ppm and µg/berry basis during the maturation of White Riesling grapes. The concentration of each of the hydroxycinnamic acid-tartaric acid esters and two proposed triesters of caffeic or p-coumaric acid, tartaric acid and glucose is also given for 11 other black and white varieties of V. vinifera at or near maturation.
We report a case of intrauterine stroke first noted on the prenatal ultrasound study performed to assess fetal growth and estimate the date of confinement. REPORT OF A CASE A 2,500-g male infant was born spontaneously following an uneventful pregnancy and delivery. Prenatal visits had been irregular. At 33 weeks, intrauterine ultrasound had been performed for dating purposes and assessment of fetal head size. This had shown increased biparietal diameter and decreased cerebral parenchymal density in the left hemisphere (Fig 1). Apgar scores were 8 at one minute and 9 at five minutes. Gestational age assessment by the Dubowitz method was compatible with 34-week gestation. Head circumference was 36.5 cm (95th percentile), with abnormal transillumination over the left hemisphere. The infant was markedly hypotonic, with poor head control. A computed tomographic (CT) scan of the head showed a prominent low-density area that occupied the entire upper half of the
