Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:P06889 (Mol)
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Intravenous (iv) administration of 5 microgram of arginine vasotocin (AVT) into urethane-anesthetized, castrated male rats had no effect on plasma prolactin titers as compared to the rise in prolactin levels observed in intact AVT-treated rats. However, when castrated rats were first treated for two days with 2.5 mg/day of testosterone propionate and then challenged with a 5-microgram dose of AVT, the prolactin surge values obtained were comparable to those seen in intact AVT-treated rats. Conversely, treatment of intact rats for two days with 25 mg/day of the anti-androgen, cyproterone acetate, blocked the prolactin-releasing activity of AVT. In a separate experiment, treatment of castrated rats for two days with 2.5 mg/day of testosterone, androsterone or 50 microgram of estradiol benzoate and 25 mg progesterone, completely restored the prolactin-releasing activity of AVT. Similar treatment with 2.5 mg/day of androstenedione or dihydrotestosterone was without effect in restoring this response to AVT. It is concluded that the presence of gonadal steroids is essential to the action of AVT in provoking the release of prolactin in urethane-anesthetized male rats.
Mol Cell Endocrinol 1978 Dec
PMID:Effect of several androgens, cyproterone acetate or estrogen-progesterone on the prolactin-releasing activity of arginine vasotocin in castrated male rats. 73 24

47 types of green feeds and roughages were subjected to an in-vitro fermentation with dilute ruminal fluid. The volatile fatty acids produced in this process were determined quantitatively in accordance with the method of digestibility estimation proposed by Tilley and Terry (1963). An average of 5 Mol FFS (FFS=volatile fatty acids) was found per kg of dried feed, a value is also reported in the literature. The ratios of acetate to propionate to n-butyrate to iso-butyrate to n-valerianate were 64.2 : 25.4 : 6.6 : 0.8 : 1.5 : 1.5. In this ratio, propionic acid predominated so that acetic acid and n-butyric acid were misrepresented compared with the data of in-vivo measurements made for the corresponding foodstuffs. Consequently, it is only within certain limits that values of FFS concentrations obtained in vitro may be used for estimating net energy data, disregardful of the fact that the FFS are the main source of metabolizable energy in ruminants. The reliability index for an estimation of Starch Equivalents and NEFr based on the above-mentioned method was found to be considerable lower (0.71 and 0.80) than that based on in-vitro digestibility measurements (0.86).
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PMID:[Estimation of the net energy using volatile acids produced in the process of in-vitro digestion with ruminal fluid]. 86 14

The lethal and mutagenic effects of 5 mug/ml N-methyl-N'-nitro-N-nitrosoguanidine (MNNG) were maximal during the nuclear S-period of synchronously grown Chlamydomonas reinhardtii. This was revealed by a 50% drop in survival and a 50- to 100-fold increase in the recovery of slow-growth mutants (up to 40% of the survivors) which were first recognized as small colonies on agar medium. Partial characterization of these isolates revealed about 50% to be stable on subculture, and several were demonstrated to be either acetate-dependent, dark-lethal (light-dependent), or acetate-sensitive mutants. There was no significant increase of lethality or of slow-growth mutants correlated with treatment during the chloroplast DNA replication phase of the cell-cycle. The results of genetic analysis with 13 mutants induced during the nuclear S-period were consistent with their nuclear origin. These analyses were hampered by the high proportion of lethality among the progeny of most crosses. It is concluded that the enhanced mutant induction among nuclear S-phase cells may indicate preferential mutagenesis of replication fork DNA and induction of multiple-closely-linked mutations, as in some bacteria. Consequently, for C. reinhardtii, caution should be exercised in drawing relationships between abnormal behavioral and biochemical phenotypes in MNNG-induced mutants.
Mol Gen Genet 1976 Sep 23
PMID:Lethal and mutagenic effects of nitrosoguanidine on synchronized Chlamydomonas. 96 59

1. Oral administration of DL-alpha-tocopheryl nicotinate (EN) (0-04 or 0-2 mmol day-1 kg-1) or DL-alpha-tocopharyl acetate (EA) (0-2 mmol day-1 kh-1) delayed the progress of hypertension in unilaterally nephrectomized rats, which were treated with deoxycorticosterone and salt, and in genetically hypertensive rats (SHR) which were given sodium chloride solution. Suppression of body weight gain, incidence of pneumonia and mortality were reduced by treatment with EN or EA. 2. Severe hypertension in old SHR (9 months) further progressed, when drinking water was replaced by sodium chloride solution, and four out of ten of these animals died of cerebral haemorrhage during 4 weeks. The administration of EN or EA prevented the increase in blood pressure and incidence of stroke.
Clin Sci Mol Med Suppl 1976 Dec
PMID:Anti-hypertensive action of DL-alpha-tocopharyl esters in rats. 107 97

Relationship of citrate synthase (EC 4.1.3.7) to the biosynthesis of glutamic acid was investigated by characterizing a new glutamic acid auxotroph FL100-D1 (glu 3) of Saccharomyces cerevisiae. Nutritional requirement of the mutant was satisfied by L-glutamic acid, L-glutamic acid peptide as well as several analogs of glutamic acid, but not by proline, ornithine, arginine, lysine or aspartic acid. The mutant was unable to utilize nonfermentable carbon sources, glycerol, acetate or lactate. Mutant glu3 unlike aconitaseless glutamic acid auxotroph glu 1, failed to accumulate 14C-citric acid in vivo from 1-14C-sodium acetate or U-14C-glutamic acid. Both spectrophotometric and radioactive assay procedures demonstrated a lack of significant citrate synthase activity in the dialysed extract of the mutant compared to the wild type strain. Mutant glu 3 complemented with glu 1 and glu 2 individually in vivo and exhibited a significant aconitase (EC 4.2.1.3) activity in vitro.
Mol Gen Genet 1975 Sep 08
PMID:Citrate synthaseless glutamic acid auxotroph of Saccharomyces cerevisiae. 110 43

1. The effect of progesterone on renal haemodynamics and intrarenal sodium handing was evaluated in thirteen normal men on a constant diet. Clearances were measured during maximal water diuresis and again 4-7 days later, this time 3 h after progesterone was given intramuscularly. Seven additional studies were performed 3 days after progesterone administration. Another four tests were performed on volunteers who had manifested renal 'escape' from the sodium-retaining effect of deoxycorticosterone acetate. 2. In acute progesterone studies glomerular filtration rate was unchanged, whereas effective renal plasma flow increased, so that filtration fraction decreased significantly. A similar in crease in urinary sodium occurred whether subjects received a low or high sodium diet. Indices which related to the distal delivery of filtrate (fractional urine flow and the sum of fractional free water and sodium clearances) increased significantly in both groups. The progesterone-induced increase in sodium excretion was not related to changes in plasma renin activity, renin substrate or urinary aldosterone. After 3 days of progesterone, the increase of sodium excretion was less than in the acute studies and urinary aldosterone increased tow- to four-fold. Progesterone failed to produce an acute increse in urinary sodium in subjects hyperexpanded by administration of exogenous mineralocorticoids. 3. Results suggest that the acute natriuretic action of progesterone is in part independent of aldosterone inhibition and that progesterone may inhibit sodium reabsorption at proximal as well as distal sites in the nephron.
Clin Sci Mol Med 1975 Aug
PMID:Effect of progesterone on renal sodium handling in man: relation to aldosterone excretion and plasma renin activity. 114 5

Androgen binding activity in the testis has two components. One component, ABP, has been shown to be produced by Sertoli cell cultures for at least 9 days in the absence of exogenously added hormones. FSH (10-100 microgram/ml) markedly enhances the secretion of ABP. MIX has a potentiating effect after long treatment intervals (7 days). In order to study the second component, intracellular androgen receptor, a nuclear exchange assay was developed. Competition for exchange activity using 3H-dihydrotestosterone was significant for a 500 fold excess of testosterone, dihydrotestosteron, progesterone, and cyproterone acetate. The exchange activity was increased 2-10 fold by prior treatment in vitro or in vivo with testosterone. Significant exchange activity was found in long-term hypophysectomized adult and immature animals and in tubule and germ cell fractions. In isolated germ cell fractions, the highest concentration of exchange activity was associated with the most mature elements. These data suggest that androgen exchange activity may exist in both Sertoli cell and germ cell fractions and suggest that the mechanism of action of androgens in the testis is quite complex.
Curr Top Mol Endocrinol 1975
PMID:Androgen binding in the testis: in vitro production of androgen binding protein (ABP) by Sertoli cell cultures and measurement of nuclear bound androgen by a nuclear exchange assay. 123 74

1. The pathogenesis of the mental retardation in phenylketonuria remains obscure. Leucocytes have proved of value in the study of other inborn errors of metabolism. The lymphocyte is a suitable model cell for the study of mammalian metabolism, because of its ability to divide in vitro in response to various stimuli. 2. We have examined the effects of phenylalanine, phenylpyruvate, phenyl-lactate and phenylacetate on the human leucocyte and the resting and phytohaemagglutinin-stimulated rabbit lymphocyte. 3. Phenylpyruvate and phenyl-lactate reduced acetate incorporation into leucocyte lipid by 38% and 48% respectively. Only phenyl-lactate reduced acetate incorporation into the resting and stimulated lymphocyte, by 20% and 34% respectively. 4. Glucose incorporation into leucocyte lipid was unaffected by phenylalanine, phenylpyruvate and phenyl-lactate. Only phenyl-lactate inhibited (46%) the production of CO2 from glucose. 5. Phenylalanine and leucine incorporation into trichloroacetic acid-insoluble material of resting and stimulated lymphocytes was inhibited by phenyl-lactate (10-42%), phenylpyruvate (27-57%) and phenylacetate (19-39%). 6. Uridine incorporation into resting and stimulated cells was inhibited by phenyl-lactate (22-26%), phenylpyruvate (42-52%) and phenylacetate (20%). 7. Thymidine incorporation into resting lymphocytes was reduced by phenyl-lactate, phenylpyruvate, phenylacetate and phenylalanine by 12-26%. Incorporation into the stimulated cell was inhibited by phenylpyruvate and phenyl-lactate (90%) and phenylacetate (66%). 8. Phenylalanine inhibited lymphocyte pyruvate kinase and phenylpyruvate inhibited citrate synthetase. 9. These results are compared with published data relating to experimental hyperphenylalaninaemia and the effects of these metabolites on nervous tissue in vitro.
Clin Sci Mol Med 1975 Oct
PMID:Effect of phenylalanine and its metabolites on the metabolism of leucocytes and lymphocytes. 123 28

The chicken ovalbumin gene is subject to multihormonal regulation. Maximal expression of it requires not only the synergistic effects of estrogen and corticosterone, but also the permissive effects of insulin. In addition to effects on transcription, the stability of its message is greatly enhanced by estrogen. Furthermore, two signal transduction pathways involving protein kinases have been implicated in the regulation of the ovalbumin gene. To better define the role of second messengers on expression of the ovalbumin gene, the effects of the protein kinase-C (PKC) and the cAMP-dependent protein kinase (PKA) pathways on the endogenous levels of ovalbumin mRNA and the transcription of an ovalbumin fusion gene were investigated. Primary cultures of oviduct cells were treated with phorbol 12-myristilate 13-acetate (an activator of PKC) or with forskolin and 3-isobutyl-1-methylxanthine (an activator of PKA) alone, activators plus estrogen and corticosterone, or activators plus both steroids and insulin. The results indicate that phorbol 12-myristilate 13-acetate causes a dramatic destabilization of ovalbumin message, resulting in a reduction in ovalbumin mRNA levels. In contrast, the activators of the PKA system can substitute for insulin and, thereby, increase expression of the ovalbumin gene synergistically with the steroids. The effect of the activators of the PKA system is at the level of transcription. Thus, in chicken oviduct cell cultures, the PKA and PKC signal transduction pathways act in opposing ways to modulate the steroid-induced expression of the ovalbumin gene.
Mol Endocrinol 1992 Sep
PMID:Regulation of expression of the chicken ovalbumin gene: interactions between steroid hormones and second messenger systems. 127 83

A morphometric analysis of bone marrow trephine biopsies has been performed to study the frequency and planimetric characteristics of so-called atypical micromegakaryocytes in chronic myeloid leukemia (CML) and myelodysplastic syndromes (MDS). In addition, an attempt was made to discriminate this particular cell population from small immature elements of megakaryocytopoiesis, such as promegakaryoblasts and megakaryoblasts. The staining reactions employed included periodic acid-Schiff (PAS), alpha-naphthyl acetate esterase (ANAE) and immunohistochemistry with a monoclonal antibody against platelet glycoprotein IIIa (Y2/51-CD61). Comparison of the various staining reactions applied to the different megakaryocytic elements together with morphometric measurements resulted in a clearcut identification of promegakaryoblasts. These were defined as the earliest immature and exclusively CD61-positive precursors. Atypical micromegakaryocytes were characterized by their dysplastic features and strong ANAE reactivity in addition to their positive CD61 staining. When stringent diagnostic criteria (diameter ranging between 10 to 15 microns, mean size about 12 microns) were applied, this abnormal cell population comprised less than 10% of total megakaryocytopoiesis in CML and MDS. It may be assumed that dysmegakaryocytic features in the latter disorders are partially generated by small to medium-sized megakaryocytes (diameter less than 30 microns). In conclusion, the relative frequency of promegakaryoblasts in the normal bone marrow (range 6-8%) is confirmed by evaluation of the immunohistochemical and cytochemical staining methods (CD61 and ANAE). Furthermore, the ANAE reaction facilitates the recognition of atypical micromegakaryocytes as well as small megakaryocytes. Thus cytochemistry provides a better insight into alterations of these cell lineages in various pathological conditions.
Virchows Arch B Cell Pathol Incl Mol Pathol 1992
PMID:Atypical micromegakaryocytes, promegakaryoblasts and megakaryoblasts: a critical evaluation by immunohistochemistry, cytochemistry and morphometry of bone marrow trephines in chronic myeloid leukemia and myelodysplastic syndromes. 127 89


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