Characteristics of prolactin-releasing response to salsolinol (SAL) and thyrotropin-releasing hormone (TRH) in ruminants.

The secretion of prolactin (PRL) is stimulated by thyrotropin-releasing hormone (TRH), and inhibited by dopamine (DA). However, we have recently demonstrated that salsolinol (SAL), a DA-derived endogenous compound, is able to stimulate the release of PRL in ruminants. The aims of the present study were to compare the characteristics of the PRL-releasing response to SAL and TRH, and examine the relation between the effects that SAL and DA exert on the secretion of PRL in ruminants in vivo and in vitro. Three consecutive intravenous (i.v.) injections of SAL (5mg/kg body weight (b.w.): 19.2micromol/kgb.w.) or TRH (1microg/kgb.w.: 2.8nmol/kgb.w.) at 2-h intervals increased plasma PRL levels after each injection in goats (P<0.05); however, the responses to SAL were different from those to TRH. There were no significant differences in each peak value between the groups. The rate of decrease in PRL levels following the peak was attenuated in SAL-treated compare to TRH-treated animals (P<0.05). PRL-releasing responses to SAL were similar to those to sulpiride (a DA receptor antagonist, 0.1mg/kgb.w.: 293.3nmol/kgb.w.). In cultured bovine anterior pituitary (AP) cells, TRH (10(-8)M) significantly increased the release of PRL following both 15- and 30-min incubation periods (P<0.05), but SAL (10(-6)M) did not increase the release during the same periods. DA (10(-6)M) completely blocked the TRH-induced release of PRL for a 2-h incubation period in the AP cells (P<0.05). Sulpiride (10(-6)M) reversed this inhibitory effect but SAL (10(-6)M) did not have any influence on the action of DA. These results show that the mechanism(s) by which SAL releases PRL is different from the mechanism of action of TRH. Furthermore, they also show that the secretion of PRL is under the inhibitory control of DA, and SAL does not antagonize the DA receptor's action.

A case of symptomatic heterozygous female Fabry's disease without detectable mutation in the alpha-galactosidase gene.

We report a case of symptomatic heterozygous female Fabry's disease with low alpha-galactosidase blood activity. We could not find any mutations in the coding regions of either the signal peptide or the enzyme subunit in our case.

Determinations of free and bound ethanol, acetaldehyde, and acetate in human blood and urine by headspace gas chromatography.

The improved PCA method leads to accurate measurement of ethanol, acetaldehyde, and acetate in blood and urine by headspace gas chromatography. It is important to prevent the formation of artifactual acetaldehyde from coexistent ethanol. The column used for detection of alcohol metabolites was the fused silica glass capillary column bonded with PEG-20M or the fused silica glass capillary column of Pora PLOT Q. In bound alcohol metabolites, recent measurements of hemoglobin-associated acetaldehyde in blood, and ethanol conjugate and acetaldehyde conjugate in urine are reviewed and described as a marker of alcohol abuse.

Frequency distribution of D1S80 (MCT118) locus polymorphism in a Qatari population.

The genotype and allele frequencies at the D1S80 locus were determined in a Qatari population sample (n = 300) using the polymerase chain reaction with subsequent electrophoretic separation of the amplified DNA fragments. Twenty-two different alleles containing 15-39 repeats of the basic 16-bp unit and 78 genotypes were distinguished; the alleles with 18 and 24 repeat units were the most common, with frequencies of 0.2117 and 0.4233, respectively. The observed and expected genotype values show no significant deviation from Hardy-Weinberg equilibrium. The power of discrimination for the D1S80 locus in the Qatari population is 0.9137, and the chance of exclusion is 59.01%.

Effects of bezafibrate on ethanol oxidation in rats.

Bezafibrate is used to lower serum lipid levels in humans. Fibrate derivatives induce an enzyme participating in the beta-oxidation by peroxisomes. We gave ethanol (2 g/kg) orally to bezafibrate-treated (300 mg/kg) male rats of the Wistar strain. Blood ethanol levels were remarkably lower and ethanol elimination stood at 432.6 mg/kg/hr (control, 336.6 mg/kg/hr) in the bezafibrate group (p < 0.01). Blood acetate levels were conversely higher in the bezafibrate group. The fatty acid beta-oxidation activity of liver peroxisome in bezafibrate-treated, clofibrate-treated, or gamma-linolenic acid-treated rats for 4 days was assayed. The activity was 5.8-fold higher in rats given bezafibrate, 5.4-fold in the clofibrate (p < 0.01), and 2.0-fold in the gamma-linolenic acid (p < 0.05). Alcohol dehydrogenase and aldehyde dehydrogenase activity of cytosol in the liver was not induced by the hypolipidemic drugs, but aldehyde dehydrogenase activity in the liver homogenate was induced. From foregoing results, bezafibrate induced in the organism beta-oxidation by peroxisomes and increased H2O2 production, which led to augmented ethanol metabolism by catalase.

The sign of Leser-Trélat associated with carcinoma of the stomach.

The sign of Leser-Trélat, which refers to the sudden appearance and rapid increase in size and number of seborrheic keratosis associated with a visceral malignant tumor, is very uncommon. This case concerns a 54-yr-old woman presenting with Leser-Trélat's sign associated with advanced gastric cancer. Seborrheic keratosis faded after resection of the tumor, but returned when the cancer recurred. At that time, 24-h urinary excretion of epidermal growth factor determined by radioreceptor assay was slightly elevated. Epidermal growth factor may play a part in the development of Leser-Trélat's sign.

Macroautoradiographic and densitometric studies of [14C]dimethadione in rats: accumulation of the compound in the pancreas.

Whole-body autoradiographic and densitometric distribution studies were performed on rats to investigate the accumulation of [14C]dimethadione (DMO) in the pancreas. [14C]DMO was intravenously administered at a dose of 167 microCi/0.5 mg/kg. Animals were sacrificed 1, 15, 30, 60 and 180 min after administration of the radioactive compound. The compound was found to rapidly distribute in all body tissues. The distribution pattern of the compound in the pancreas was spotty or linear due to the presence of the radioactive compound in blood of intrapancreatic vessels and in pancreatic ducts at higher levels than parenchyma. The radioactivity of pancreatic ducts became more evident with time, indicating the gradual accumulation of the compound in the ducts. These findings provide morphological evidence that DMO is accumulated in the pancreas and possibly eliminated from pancreatic juice. Densitometry revealed that the levels of radioactive compound in the pancreas were virtually as high as those in the liver and kidney.

Stabilization of human serum alkaline phosphatase to histidine-induced heat inactivation by tryptic digestion.

1. Serum alkaline phosphatase [EC 3.1.3.1] was strongly inactivated by histidine during incubation at pH 8.0 and 45degrees; however, tryptic digestion of the serum strongly protected the enzyme against inactivation by histidine. In the absence of histidine, however, neither heat inactivation of the phosphatase nor the effect of trypsin [EC 3.4.21.4] was observed. Factors affecting the alkaline phosphatase inactivation were studied further. 2. The effect of trypsin on the histidine-induced heat inactivation differed considerably according to the tissue source of the enzyme, which suggests a possible method for distinguishing alkaline phosphatase isoenzymes.