A common nomenclature for members of the tissue (glandular) kallikrein gene families.
Explore the source record for details and available documents.
Animals↗
Biomedical subjects
J A Clements
Publications and source records attributed to J A Clements.
The Anagen system for automated fluorometric immunoassay.
We describe a new discrete microprocessor-controlled analyzer, the AN2000, which fully automates fluorometric immunoassays by using a magnetic separation of the solid phase and an alkaline phosphatase label. It can operate in random-access or batch mode with a dwell time typically less than 20 min. The analysis rate is 75 samples per hour and the system can hold refrigerated reagents for as many as 20 different analytes. The substrate and wash buffer are common to all analytes. The system can hold as many as 80 samples at once. The operator can select from the menu-driven operator interface any combination of the available analytes to be run for each sample, using either the touch screen or the keyboard. Results are calculated from a stored calibration curve that is stable for greater than or equal to 1 month. The AN2000 is capable of automating most assay formats because the available timings, volumes, incubations, and wash cycles can be used in any combination.
Alkaline Phosphatase↗
Localization of immunoreactive beta-endorphin and adrenocorticotropic hormone and pro-opiomelanocortin mRNA to rat testicular interstitial tissue macrophages.
Pro-opiomelanocortin (POMC) gene expression and POMC peptides have been demonstrated in the Leydig cells of the testis, although selective removal of the Leydig cells with the cytotoxic drug ethane dimethane sulfonate did not significantly reduce levels of testicular POMC mRNA or peptides in adult rats. Since macrophages in the rat spleen synthesize POMC peptides, we investigated whether isolated macrophages from the adult rat testis may be an additional source of POMC-derived peptides. Testicular macrophages were isolated by collagenase treatment of adult rat testes and adherence to siliconized glass coverslips; the biological, cytochemical and immunological characteristics of the attached cells were compared with those of Leydig cells purified by Percoll gradient centrifugation. Macrophages in the cell preparations were identified by positive esterase cytochemical staining, latex bead ingestion, and immunocytochemical staining with ED2 (a macrophage-specific monoclonal antibody), and an absence of 3 beta-hydroxysteroid dehydrogenase cytochemical staining. Leydig cells in the purified preparations were positive for 3 beta-hydroxysteroid dehydrogenase and esterase staining but negative with ED2, and were not phagocytic. Based on these criteria, the purities of the macrophage and Leydig cell preparations employed in this study were estimated to be 87 +/- 4% and 91 +/- 3%, respectively. Cytoplasmic beta-endorphin (beta EP) immunoreactivity (ir) was present in 62 +/- 9% of cells in the purified Leydig cell preparations--confirming these cells as a source of POMC-derived peptides. In addition, ir-beta EP and ir-ACTH were localized to the cytoplasm of a similar proportion of cells (beta EP, 62.5 +/- 5%; ACTH, 64 +/- 5%) in macrophage preparations.(ABSTRACT TRUNCATED AT 250 WORDS)
Adrenocorticotropic Hormone↗
Regulation of gene expression and cellular localization of prostaglandin synthase by oestrogen and progesterone in the ovine uterus.
Expression of the gene for prostaglandin synthase (PGS) was examined in whole endometrial tissue derived from ewes during the oestrous cycle (Days 4-14), on Day 15 of pregnancy and following ovariectomy and treatment with ovarian steroid hormones. Whilst no significant differences were seen in PGS mRNA concentrations analysed by Northern blot analysis in endometrial tissue during the oestrous cycle or in early pregnancy, treatment of ovariectomized (OVX) ewes with oestradiol-17 beta markedly reduced endometrial PGS mRNA concentration. There was no difference in PGS mRNA concentration in ewes treated with progesterone, either alone or in conjunction with oestrogen, from that in OVX controls. In contrast, differences in immunolocalization of PGS observed in uterine tissue from OVX-steroid-treated ewes were much more marked and reflected similar changes seen previously in the immunocytochemical distribution of endometrial PGS during the oestrous cycle. In OVX ewes and those treated with oestrogen, immunocytochemical staining for PGS was seen in stromal cells, but little immunoreactive PGS was located in the endometrial epithelial cells. However, in ewes treated with progesterone alone or with oestrogen plus progesterone, PGS was found in luminal and glandular epithelial cells and in stromal cells. Intensity of immunostaining for PGS in endothelial cells and myometrium did not differ between the treatments. Thus, whilst oestrogen lowers PGS mRNA in the endometrium, presumably in stroma, it may also increase the stability of the enzyme itself in the stromal cells. Although oestradiol-17 beta has no effect on PGS in endometrial epithelium, progesterone stimulates the production of PGS in endometrial epithelial cells without altering the overall abundance of PGS mRNA in the endometrium as a whole. Conceptus-induced changes in PGF-2 alpha release by ovine endometrium would not appear to be mediated via effects on PGS gene expression or protein synthesis.
Animals↗
Initial clinical trial of EXOSURF, a protein-free synthetic surfactant, for the prophylaxis and early treatment of hyaline membrane disease.
EXOSURF is a protein-free surfactant composed of 85% dipalmitoylphosphatidylcholine, 9% hexadecanol, and 6% tyloxapol by weight. A single dose of 5 mL of EXOSURF per kilogram body weight, which gave 67 mg of dipalmitoylphosphatidylcholine per kilogram body weight, or 5 mL/kg air was given intratracheally in each of two controlled trials: at birth to neonates 700 through 1350 g (the prophylactic trial, n = 74) or at 4 to 24 hours after birth to neonates greater than 650 g who had hyaline membrane disease severe enough to require mechanical ventilation (the rescue trial, n = 104). In both studies, time-averaged inspired oxygen concentrations and mean airway pressures during the 72 hours after entry decreased significantly (P less than .05) in the treated neonates when compared with control neonates. Thirty-six percent of the treated neonates in the rescue study had an incomplete response to treatment or relapsed within 24 hours, suggesting the need for retreatment in some neonates. In the rescue trial, risk-adjusted survival increased significantly in the treated group. There were no significant differences in intracranial hemorrhages, chronic lung disease, or symptomatic patent ductus arteriosus between control and treated infants in either trial.
Administration, Inhalation↗
Tissue-specific regulation of the expression of rat kallikrein gene family members by thyroid hormone.
We have altered the thyroid hormonal status of both male and female rats and examined the expression of six functional members of the rat kallikrein gene family (PS, S1, S2, S3, K1 and P1) in the submandibular gland (SMG), kidney, prostate, testis and anterior pituitary gland (AP) of these animals. On Northern-blot analysis with gene-specific oligonucleotide probes, the steady-state mRNA levels of S1, S2, S3, K1 and P1 were all dramatically altered in the SMG of male and female rats treated with propylthiouracil (PTU; 100 mg/litre of drinking water) or thyroxine (T4; 10 micrograms/100 mg body wt.) for 3 weeks. The SMG mRNA levels of these five genes were all lowered (30-90%) in hypothyroid (PTU-treated) male and female rats and elevated (1.4-4-fold, male; 1.5-11-fold, female) in the hyperthyroid (T4-treated) and PTU/T4-treated animals. In contrast, PS (true kallikrein) mRNA levels in the male or female SMG or kidney were essentially unchanged. K1 mRNA levels in the kidney were considerably less responsive to thyroid status than those in the SMG. Changes in S3 and P1 mRNA levels in the prostate were also variable, but essentially unaffected by these treatments. AP PS mRNA levels were also unaffected by changes in thyroid-hormonal status, as were levels of a novel P1-like mRNA in the testis. In summary, these studies demonstrate that the same kallikrein gene family member(s) may be differentially regulated by thyroid hormones in the rat SMG, kidney, prostate and pituitary, and thus further extend the concept of tissue-specific expression and hormonal regulation of the kallikrein gene family in the rat.
Animals↗
Tissue-specific developmental expression of the kallikrein gene family in the rat.
Using a series of gene-specific oligonucleotide probes, we have explored the developmental pattern of expression of six members of the rat kallikrein gene family (PS, S1, S2, S3, K1, and P1) in the submandibular gland (SMG) and kidney of both sexes, the prostate and testis of the male, and the anterior pituitary gland (AP) of the female rat. PS (true kallikrein) mRNA was detected in early neonatal life in the SMG and kidney of both sexes. K1, a second kallikrein gene family member expressed in the adult kidney, had a developmental pattern similar to PS in the kidney. In contrast, tonin (S2), S3, K1, and P1, all of which are expressed in the adult SMG, did not reach detectable SMG mRNA levels until puberty in either the male or female rat. Both S3 and P1, which are expressed in the adult prostate, and the novel P1-like mRNA previously detected in the adult rat testis, first appeared in early puberty. In the female AP, PS mRNA levels were not detected until early puberty and thus exhibited a developmental profile different from that of prolactin. The demonstration that S1, S2, S3, P1, and K1 are not expressed in the SMG or prostate until puberty is consistent with the expression of these genes in these tissues being androgen-regulated; the first appearance of PS mRNA in the female AP in early puberty similarly reflects the estrogen dependence of PS gene expression in this tissue. The presence of PS mRNA levels in the SMG and kidney prior to sexual maturation reflects the androgen independence of PS gene expression and suggests that PS (true kallikrein) may play a constitutive and/or developmental role in SMG or renal physiology.
Animals↗
Oestrogen administration and the expression of the kallikrein gene family in the rat submandibular gland.
Using a series of oligonucleotide probes (18-21 mers) specific for members of the rat kallikrein/tonin (arginyl-esteropeptidase) gene family (PS, S1, S2, S3, K1, P1), we have shown by Northern blot analysis that all six genes are expressed in the submandibular gland (SMG), with PS (true kallikrein) the most abundant in both male and female rats. Though female levels of PS mRNA are similar to that in the male, levels of mRNA from both the kallikrein-like (S1, K1, P1) and tonin (S2)/tonin-like (S3) genes are all substantially lower in the female than in the male rat. In contrast with the oestrogen dependence of anterior pituitary kallikrein (PS) gene expression, oestrogen administration (6 micrograms/day for 8 days) to castrate male or female rats is without effect on PS or S1, S2, S3, K1, P1 mRNA levels in the SMG. These findings suggest a tissue-specificity in the oestrogen regulation of true kallikrein gene expression in the two tissues. In intact male rats, oestrogen administration lowers SMG levels of S1, S2, S3, K1, and P1 but not PS mRNA to castrate levels, presumably by suppression of the pituitary/gonadal axis, consistent with the previously reported androgen dependence of SMG expression of these genes with the exception of PS.
Animals↗
Interactions between the seminiferous tubules and Leydig cells of the testis.
Explore the source record for details and available documents.
Animals↗
Pulmonary surfactant and its apoproteins.
Explore the source record for details and available documents.
Animals↗
Kallikrein-gene expression in the rat gastrointestinal tract.
The serine proteinase glandular kallikrein has been demonstrated in the gastrointestinal tract, although there is some doubt as to whether it is synthesized there or derives from exocrine-gland secretions. Using a rat pancreatic kallikrein cRNA probe we have demonstrated kallikrein-like gene expression in the corpus, duodenum, jejunum, ileum, caecum and colon, and compared the pattern of expression with that of the gastrointestinal peptides somatostatin, gastrin and glucagon. In addition, using a panel of oligonucleotide probes specific for various members of the rat kallikrein-gene family, we have shown that the kallikrein-like gene expressed appears to be expressed as true kallikrein.
Animals↗
Gonadal steroids and anterior lobe dynorphin in the male rat.
Immunoreactive (ir)-dynorphin levels were measured, and the species characterized by high performance liquid chromatography (HPLC), in the pituitary and hypothalamus of intact and castrate male rats. On HPLC, ir-dynorphin co-eluted with authentic dynorphin A 1-8, dynorphin A 1-17 and dynorphin 1-32 in the hypothalamus and intermediate lobe; in two different reversed phase (RP)-HPLC systems, anterior lobe ir-dynorphin co-eluted uniquely with dynorphin 32 (4K dynorphin). Anterior lobe levels of total ir-dynorphin were significantly lowered 7 days after castration, while HPLC profiles in all tissues remained unchanged. The change in anterior pituitary ir-dynorphin levels was reversed in a dose-related manner by dihydrotestosterone (15-500 micrograms/100 g b. wt/day); estradiol benzoate (3 micrograms/100 g/day) was without effect. The changes on castration and androgen administration suggest that gonadal steroids play a role in the regulation of dynorphin, as well as gonadotrophins and prolactin, within the anterior pituitary gland.
Animals↗
Regulation of liver angiotensinogen mRNA by glucocorticoids and thyroxine.
This study examines the immediate and longer-term changes in angiotensinogen mRNA and in plasma angiotensinogen which follow the withdrawal and replacement of glucocorticoids or thyroxine. RNA from rat liver was analysed by Northern blot and dot-blot hybridization with a 40-mer oligodeoxynucleotide probe specific for angiotensinogen mRNA. Adrenalectomy decreased plasma angiotensinogen and angiotensinogen mRNA to 55 and 50% of control values respectively over a period of 16 days. Similar decreases were obtained after propylthiouracil (1 mg/kg for 16 days) treatment, except when injected simultaneously with T3 (3 micrograms/kg/day). Over the same period plasma renin activity increased in adrenalectomized rats from 4.1 +/- 0.8 to 7.0 +/- 1.5 pmol angiotensin I (AI)/ml/h, and decreased in propylthiouracil-treated rats from 3.8 +/- 0.4 to 1.6 +/- 0.4 pmol AI/ml/h. Approximate half-times of 2-3 days were calculated for both plasma angiotensinogen and angiotensinogen mRNA post-adrenalectomy or after propylthiouracil treatment. Dexamethasone (400 micrograms/kg, i.m.) given to intact rats rapidly increased angiotensinogen mRNA to a maximum of 250% of control by 8 h and with a half-maximal response of 2.8 h. Plasma angiotensinogen responded similarly, apart from an initial delay of 2 h. Treatment with different doses of propylthiouracil and dexamethasone showed that responses were dose-related. We conclude that changes in plasma angiotensinogen and angiotensinogen mRNA are closely correlated, and that under various physiological circumstances angiotensinogen mRNA has a rapid rate of accumulation but a slow rate of decay.
Adrenalectomy↗
Effect of ethane dimethane sulphonate on proopiomelanocortin (POMC) mRNA and POMC-derived peptides in the rat testis.
Recent studies have shown that both proopiomelanocortin (POMC)-derived peptides and a range of POMC gene transcripts are present in the testis. Previous immunocytochemical studies have reported immunoreactive (ir)-beta-endorphin (EP) and ir-ACTH to be localized in the Leydig cells, and ir-NacEP in spermatogonia and primary spermatocytes. In the present study, we have further examined the hypothesis that testicular Leydig cells are the principal site of synthesis of these peptides, by determining the effects of the administration of the cytotoxic drug ethane dimethane sulphonate (EDS) which selectively destroys the Leydig cells of the testis. As expected, serum testosterone levels fell and serum FSH/LH levels increased within 3 days of EDS administration, returning to normal levels 4-8 weeks later. In contrast, the testicular content of POMC-derived peptides and POMC mRNA levels in these animals was not significantly altered throughout the experimental period. In addition, POMC mRNA was not detected in a purified Leydig cell preparation derived from adult male rats, and POMC-derived peptides were also undetectable in the media of a similar preparation following cell culture. These data suggest that in the adult the predominant site of rat POMC gene expression is in testicular interstitial cells other than Leydig cells.
Adrenocorticotropic Hormone↗
Determination of pipothiazine in human plasma by reversed-phase high-performance liquid chromatography.
A method is described for the determination of pipothiazine in human plasma, based on reversed-phase HPLC. The method has been applied in a pharmacokinetic study of pipothiazine in six psychiatric patients receiving repeated depot intramuscular injections for six months. A number of compounds likely to be taken concurrently by patients were tested for potential to interfere with the assay. There was no evidence of "dose-dumping" in the period following injection. Comparison of the pharmacokinetic profiles after the first and sixth injections showed no evidence of drug accumulation.
Adult↗
Studies of the structure of lung surfactant protein SP-A.
SP-A, a glycoprotein of pulmonary surfactant, consists of an NH2-terminal domain containing a collagen-like sequence and a COOH-terminal domain with sequence homology to several Ca2(+)-dependent lectins. We have compared the size, thermal stability, and secondary structure of recombinant SP-A, the product of a fibroblast line transfected with a single human gene encoding SP-A, with natural SP-A isolated from canine and human lungs. Our results suggest both recombinant and natural SP-A are assembled as large oligomers. More variability in the degree of oligomerization was observed with recombinant human SP-A than with natural canine SP-A. As shown by collagenase digestion, the full assembly of protein subunits was dependent on an intact collagen-like domain. The cysteines in the noncollagen domain of SP-A form intrachain bonds between residues 135-226 and 204-218. The circular dichroism spectra of both recombinant and natural SP-A were consistent with the presence of a collagen-like triple helix. As determined by the change in ellipticity at 205 nm, the thermal transition temperatures of canine, natural human, and recombinant SP-A were 51.5, 52.3, and 42.0 degrees C, respectively. These results suggest differences in the assembly and stability of the natural and recombinant proteins.
Amino Acid Sequence↗
Cellular uptake and processing of surfactant lipids and apoprotein SP-A by rat lung.
The intracellular pathways and the kinetics of metabolism of surfactant apoprotein and lipid, which may be recycled from the alveolar space, are largely unknown. We used a lipid-apoprotein complex made from liposomes of pure lipids in a ratio found in mammalian pulmonary surfactant plus surfactant apoprotein (SP-A, Mr = 26,000-36,000) to test some possible relationships in the recycling of these major surfactant components between intrapulmonary compartments. After intratracheal instillation of 80 microliters of an apoprotein-liposome mixture with separate radiolabels in the lipid and the apoprotein, rats were killed at times from 8 min to 4 h later. The lungs were lavaged with saline, and subcellular fractions were isolated on discontinuous sucrose density gradients. Both the [14C]lipid radiolabel and the 125I-apoprotein radiolabel demonstrated a time-dependent increase in radioactivity recovered in a lamellar body-enriched fraction. Uptake of the radiolabels into other subcellular fractions did not exhibit a clear-cut time dependence; more of the protein than the lipid radiolabel was found in the Golgi-rich and microsomal fractions. We conclude that both the lipid and apoprotein portions of lung surfactant are taken up by lung cells and are incorporated into secretory granules of the cells.
1,2-Dipalmitoylphosphatidylcholine↗
Surfactant secretion and clearance in the newborn.
Pregnant rabbits (30 days) were injected intravenously with [3H]choline 8 h before delivery. The fetuses were delivered, and lung lavage and lamellar body phospholipids (PL) were analyzed. Some newborns also received radioactively labeled surfactant intratracheally on delivery and were permitted to breathe. With time, intratracheal label decreased in lavage and appeared in the lamellar body fraction, and intravenous label accumulated in both pools. Using a tracer analysis for non-steady state, we calculated surfactant secretion and clearance rates for the newborn period. Before birth, both rates rose slightly from 1.8 micrograms PL.g body wt-1.h-1 at 6 h before birth to 7.3 at birth. Immediately after birth, secretion rate rose to 37.7 micrograms PL.g body wt-1.h-1. Between 1.5 and 2 h after birth it fell to a minimum of 1.8 micrograms PL.g body wt-1.h-1 and then rose slowly to 6.0 at 12 h. After birth, clearance rate increased less than secretion rate (maximum 24.7 micrograms PL.g body wt-1.h-1 shortly after birth) then followed the same pattern but did not balance secretion rate in the 1st day.
Animals↗