Inhibition of hypothalamic and pituitary muscarinic receptor binding by progesterone

The in vitro effects of estrogens, progestins, and their related analogs on muscarinic receptor binding sites were studied in the hypothalamic membranes prepared from ovariectomized rats. The binding assays were performed under a nonequilibrium condition. Progestins and their metabolites were active in inhibiting the binding of [3H](-)QNB to muscarinic receptors, whereas estrogenic compounds were devoid of this effect. Progesterone was also found to be active in inhibiting the binding of [3H](-)QNB to pituitary membranes. The IC50 values of progesterone and its metabolite, 17 alpha-hydroxyprogesterone, were 34 and 24 microM, respectively. The inhibitory effect of progesterone was rapid, reversible, and not dependent on divalent metal ions (Ca2+, Cu2+, Fe2+, Mg2+, Mn2+, and Zn2+). Analyses of the binding data with Scatchard and Lineweaver-Burke plots revealed that progesterone significantly increased the apparent Kd of muscarinic receptor binding sites from 0.54 (SE = +/- 0.08) nM to 2.44 (SE = +/- 0.49) nM in hypothalamic membranes and from 0.21 (SE = +/- 0.03) nM to 0.34 (SE = +/- 0.03) nM in pituitary membranes without a significant effect on the receptor density in both membrane preparations. Progesterone decreased the rate of association of [3H](-)QNB with muscarinic receptors without a significant effect on its rate of dissociation from the [3H](-)QNB-receptor complex. These results indicate that progesterone, but not estrogenic compounds, was capable of interacting with hypothalamic and pituitary muscarinic receptors in vitro.

The effects of ovarian hormones on beta-adrenergic and muscarinic receptors in rat heart

The in vitro and in vivo effects of estrogen and progesterone on muscarinic and beta-adrenergic receptors of cardiac tissue were studied in ovariectomized (OVX) rats. The binding assay for muscarinic receptors was performed under a nonequilibrium condition; whereas the binding assay for beta-adrenergic receptors, under an equilibrium condition. Estrogenic compounds and progesterone were found to have no effect on the binding of the radioligand, [3H]-dihydroalprenolol, to beta-adrenergic receptors in vitro. However, progestins but not estrogenic compounds inhibited the binding of the radioligand, [3H]-quinuclidinyl benzilate, to muscarinic receptors in vitro, with progesterone as the most potent inhibitor (IC50 = 37 microM, apparent Ki = 13 microM). Progesterone was found to decrease the apparent affinity of muscarinic receptors for [3H](-)QNB in vitro. Daily treatment of OVX rats with estradiol benzoate (4 micrograms) or progesterone (2.5 mg) for 4 days had no effect on the muscarinic or beta-adrenergic receptors with respect to the binding affinity and receptor density. However, administrations of these hormones together for 4 days caused an increase in the receptor density of muscarinic receptors without a significant effect on their apparent binding affinity; also these hormones induced a decrease in the binding affinity and an increase in the receptor density of beta-adrenergic receptors. The results of this study demonstrate that progestins are capable of interacting with the cardiac muscarinic receptors in vitro, and indicate that estrogen and progesterone have a synergistic effect to increase the receptor densities of muscarinic and beta-adrenergic receptors as well as to cause a decrease in the binding affinity of beta-adrenergic receptors in vivo.

Structure-activity relationships of steroid hormones on muscarinic receptor binding

A total of fifty steroidal compounds were tested for their inhibition on the binding of muscarinic receptor antagonist, [3H]quinuclidinyl benzilate ([3H](-)QNB), to the hypothalamic membranes prepared from male rats. Among the compounds tested, the active structures (with IC50 values less than or equal to 100 microM in parentheses) are: progesterone (40), 5 beta-pregnane-3,20-dione (40), deoxy-corticosterone (50), 5 beta-pregnane-17 alpha,21-diol-3,20-dione (30), 11-desoxy-17-hydroxycorticosterone (22), 17 alpha-hydroxyprogesterone (20), 5 beta-pregnan-17 alpha-ol-3,20-dione (24), 5 beta-androstane-3,17-dione (100), and 5 beta-dihydrotestosterone (100). By examining all the compounds tested, the following structure-activity relationship became apparent: (a) The ring A-reduced steroidal structures with a 5 beta-conformation were more potent than those with a 5 alpha-conformation; (b) 17 alpha-hydroxylation of the steroidal ring increased the steroid's inhibitory activity; (c) The C3 carbonyl group was essential for activity; (d) Reduction of the C3 carbonyl group or aromatization of the ring A abolished the steroid's inhibitory activity; (e) Oxidation of the C11 position of ring C resulted in a decrease or loss of inhibitory activity; and (f) Different modifications of the side chain of ring D by acetylation resulted in either an increase or a decrease in the inhibitory activity. The structure-activity relationship as revealed in this study might provide an insight for the synthesis of a steroidal molecule with a high affinity for the muscarinic receptor as well as for the search of a more potent and physiologically relevant steroidal metabolite possessing the ability to interact with the muscarinic receptor.

Universals and cultural differences in the judgments of facial expressions of emotion

We present here new evidence of cross-cultural agreement in the judgement of facial expression. Subjects in 10 cultures performed a more complex judgment task than has been used in previous cross-cultural studies. Instead of limiting the subjects to selecting only one emotion term for each expression, this task allowed them to indicate that multiple emotions were evident and the intensity of each emotion. Agreement was very high across cultures about which emotion was the most intense. The 10 cultures also agreed about the second most intense emotion signaled by an expression and about the relative intensity among expressions of the same emotion. However, cultural differences were found in judgments of the absolute level of emotional intensity.

The effect of estrogen on luteinizing hormone-releasing hormone binding sites in hypothalamic membranes

The binding sites for [125I]LHRH were characterized in membranes from the hypthalamus and the effect of estrogen on the binding characteristics was studied in ovariectomized female rats. The radioligand, [125I]LHRH, was found to bind specifically to membranes from the hypothalamus at a maximal level, with an optimal temperature of 0 degrees C and a pH between 7 and 8. The binding was enhanced by NaCl at a concentration of 0.1-0.2 M. The specifically bound [125I]LHRH was only displaced by LHRH, but not by sodium iodide (NaI), bovine serum albumin and other hormones, such as thyrotropin-releasing hormone, bradykinin, oxytocin, prolactin, luteinizing hormone and growth hormone. The divalent metal ions, copper (Cu2+) and mercury (Hg2+), inhibited the specific binding of [125I]LHRH completely, whereas magnesium (Mg2+) and calcium (Ca2+) caused a decrease in binding. As revealed from Scatchard plot analysis, the binding sites for [125I]LHRH in the hypothalamus had a dissociation constant of 0.40 +/- 0.03 microM and the maximum number of binding sites was 98.55 +/- 4.34 pmol/mg protein. Treatment of female rates (ovariectomized for 3 weeks) with 4 micrograms of estradiol benzoate caused a statistically significant decrease in the maximal number of binding sites without any significant effect on the dissociation constant. However, the direct addition of estradiol hemisuccinate to the membrane preparations had no statistically significant effect on the specific binding of [125I]LHRH. The present study provides the evidence that estrogen decreases the density of binding sites for [125I]LHRH in the hypothalamus in vivo.

Isolation of an antigen-specific T suppressor factor that suppresses the in vivo response of DBA/2 mice to ferredoxin

A T cell hybridoma (Fd11) has been produced from B10.D2 mice that secretes a putative antigen-specific T suppressor factor (TsF). The TsF is isolable from culture supernatants of Fd11 by affinity purification over columns containing either a monoclonal antibody (B16G) shown previously to be capable of binding murine TsF or ferredoxin (Fd), the nominal antigen to which the Fd11 TsF binds. Specificity of the Fd11 TsF for Fd was established by comparing it to another TsF isolated by us (A10 TsF) in a sandwich ELISA, and by demonstrating the specific reactivity to Fd of the hybridoma in calcium flux studies. The Fd11 affinity-purified TsF was shown to contain two major unique components with m.w. in the region of 80,000 and 35,000 when run on reducing polyacrylamide gels in the presence of sodium dodecyl sulphate. Specific immunosuppressive properties of Fd11 were demonstrated when Fd11 TsF (10 micrograms) was injected i.v. into Fd-primed syngeneic mice at the time of antigen boost. Fd11 TsF specifically and significantly diminished the secondary antibody response to Fd in DBA/2 mice.

Isolation of an antigen-specific T suppressor factor that suppresses the in vivo response of DBA/2 mice to ferredoxin

A T cell hybridoma (Fd11) has been produced from B10.D2 mice that secretes a putative antigen-specific T suppressor factor (TsF). The TsF is isolable from culture supernatants of Fd11 by affinity purification over columns containing either a monoclonal antibody (B16G) shown previously to be capable of binding murine TsF or ferredoxin (Fd), the nominal antigen to which the Fd11 TsF binds. Specificity of the Fd11 TsF for Fd was established by comparing it to another TsF isolated by us (A10 TsF) in a sandwich ELISA, and by demonstrating the specific reactivity to Fd of the hybridoma in calcium flux studies. The Fd11 affinity-purified TsF was shown to contain two major unique components with m.w. in the region of 80,000 and 35,000 when run on reducing polyacrylamide gels in the presence of sodium dodecyl sulphate. Specific immunosuppressive properties of Fd11 were demonstrated when Fd11 TsF (10 micrograms) was injected i.v. into Fd-primed syngeneic mice at the time of antigen boost. Fd11 TsF specifically and significantly diminished the secondary antibody response to Fd in DBA/2 mice.

Tamoxifen therapy in unresectable adenocarcinoma of the pancreas

Twenty-four patients with biopsy-documented unresectable ductal adenocarcinoma of the pancreas were treated with tamoxifen. Six of 15 postmenopausal female patients had documented prolonged survival, with three living greater than 2 years.

Duplication of CaMV 35S Promoter Sequences Creates a Strong Enhancer for Plant Genes

A variant of the cauliflower mosaic virus 35S promoter with transcriptional activity approximately tenfold higher than that of the natural promoter was constructed by tandem duplication of 250 base pairs of upstream sequences. The duplicated region also acted as a strong enhancer of heterologous promoters, increasing the activity of an adjacent and divergently transcribed transferred DNA gene several hundredfold, and to a lesser extent, that of another transferred DNA gene from a remote downstream position. This optimized enhancer element should be very useful for obtaining high levels of expression of foreign genes in transgenic plants.

The management of work-related back pain

This paper describes the Spinal Treatment Program at Columbia Hospital in Milwaukee. The primary goal of the program is to efficiently return the employee with a work-related back injury to the work setting. The two-phase program has been developed to provide treatment of acute injury, patient education, work hardening, and an assessment of the patient's ability to perform job tasks. Preliminary evaluative data are presented for patients treated from 1982 to 1984. The patient's discharge status (returned or did not return to work) was examined as a function of sex, age, educational level, employment category, duration of pain, or worker's compensation status. Results indicated that discharge status was significantly related to sex, employment category, duration of pain, and worker's compensation status.

Universals and cultural differences in the judgments of facial expressions of emotion

We present here new evidence of cross-cultural agreement in the judgement of facial expression. Subjects in 10 cultures performed a more complex judgment task than has been used in previous cross-cultural studies. Instead of limiting the subjects to selecting only one emotion term for each expression, this task allowed them to indicate that multiple emotions were evident and the intensity of each emotion. Agreement was very high across cultures about which emotion was the most intense. The 10 cultures also agreed about the second most intense emotion signaled by an expression and about the relative intensity among expressions of the same emotion. However, cultural differences were found in judgments of the absolute level of emotional intensity.

Characterization of an anti-idiotypic T cell hybridoma involved in the regulation of the immune response to the P815 mastocytoma

We report the isolation and characterization of a T cell hybridoma (A29) which secretes a factor that exhibits anti-idiotypic and immune-modulating characteristics. The A29 cell line is thought to represent the hybrid analog of the Ts2 suppressor cell population in the cascade regulating the immune response to the P815 tumor in DBA/2 mice. The putative TsF2 molecule is reactive with the monoclonal antibody B16G, shown previously by us to bind a public specificity of T suppressor factors (TsF). A29 TsF also exhibits specific binding to a TsF1 secreted by another T cell hybridoma, A10, which shows specificity for antigen from the P815 tumor (this has been described previously). A29 itself does not exhibit binding to P815 antigens. Affinity-purified material from A29 appears to share characteristics with A10 molecules in that the predominant material has an apparent m.w. of 70,000. Studies with calcium flux of A29 cells showed that they respond significantly and specifically on exposure to A10 TsF stimulus. We showed further that affinity-purified A29 TsF molecules can specifically suppress the in vitro generation of syngeneic CTL to the P815 tumor, and that panning of DBA/2 splenocytes over A29-TsF-coated plates renders cell populations capable of generating a higher in vitro CTL response to P815 than appropriately treated controls.

Characterization of an anti-idiotypic T cell hybridoma involved in the regulation of the immune response to the P815 mastocytoma

We report the isolation and characterization of a T cell hybridoma (A29) which secretes a factor that exhibits anti-idiotypic and immune-modulating characteristics. The A29 cell line is thought to represent the hybrid analog of the Ts2 suppressor cell population in the cascade regulating the immune response to the P815 tumor in DBA/2 mice. The putative TsF2 molecule is reactive with the monoclonal antibody B16G, shown previously by us to bind a public specificity of T suppressor factors (TsF). A29 TsF also exhibits specific binding to a TsF1 secreted by another T cell hybridoma, A10, which shows specificity for antigen from the P815 tumor (this has been described previously). A29 itself does not exhibit binding to P815 antigens. Affinity-purified material from A29 appears to share characteristics with A10 molecules in that the predominant material has an apparent m.w. of 70,000. Studies with calcium flux of A29 cells showed that they respond significantly and specifically on exposure to A10 TsF stimulus. We showed further that affinity-purified A29 TsF molecules can specifically suppress the in vitro generation of syngeneic CTL to the P815 tumor, and that panning of DBA/2 splenocytes over A29-TsF-coated plates renders cell populations capable of generating a higher in vitro CTL response to P815 than appropriately treated controls.

The case for scoliosis screening in Australian adolescents

A survey of 3660 Year 10 students, with an average age of 15 years, was carried out in a random sample of Adelaide secondary schools to determine the prevalence of structural scoliosis and the need for implementing a programme of scoliosis screening. By means of the Forward Bending Test and a specially devised scoring system 144 (3.9%) children were found to have signs that were suggestive of scoliosis; all but 12 were assessed subsequently by standardized clinical and radiological examinations. One hundred and three children were found to have structural scoliosis of 5 degrees or more; this represented a prevalence of 3.1%. The prevalence in girls (4.3%) was significantly higher than in boys (1.9%), and girls tended to have more severe curves and require treatment more frequently. Only one third (34) of the cases of structural scoliosis had been detected before this survey; most (28) of these had been detected through an earlier, subsequently discontinued, school screening programme. This study concludes that screening for scoliosis by means of a scored Forward Bending Test should be carried out in South Australian schools for all students in Year 8 and for girls in Year 10. The policy of screening boys in Year 8 should be the subject of further research. An educational programme for health professionals, parents, students and physical education teachers should support the programme.

Regional localization of 18 human X-linked DNA sequences

A series of human probes with unique sequences has been isolated from a recombinant phage library constructed with DNA obtained from a human-hamster hybrid cell line. This cell line contained the X chromosome as the only human component. For 18 of these probes, a human X-chromosome origin has been confirmed and they have been regionally assigned by a combination of techniques: dosage studies utilizing DNA from human fibroblasts carrying X-chromosome duplications and deletions; the presence or absence of hybridization to digested DNA from hybrid lines carrying fragments of the X chromosome; and in situ hybridization to metaphase chromosomes. The use of dosage as a means to regionally assign probes significantly improves resolution of the X chromosome.

Hyperprolactinemia: its electrophysiologic and pharmacologic effect on neurons of the ventromedial nucleus of the hypothalamus

Extracellular action potentials were recorded from 691 neurons in the ventromedial hypothalamus (VMH) of urethane anesthetized female rats under acute and chronic sham-operated and hyperprolactinemic conditions. Hyperprolactinemia was produced by transplanting pituitaries under the kidney capsules. Neuronal excitability was recorded and analyzed during spontaneous, baseline activity and following the iontophoretic application of prolactin, dopamine (DA) and luteinizing hormone-releasing hormone (LH-RH). No statistically significant changes were observed in the spontaneous electrical activity of VMH neurons under the conditions tested. Of the responsive neurons, approximately 90% of the neurons recorded and tested with prolactin displayed an increase in firing activity while DA produced a decrease, independent of the endogenous plasma prolactin levels (basal or elevated). However, the response to LH-RH was modified in the chronic hyperprolactinemic animal. The predominant response of VMH neurons to LH-RH in acute sham-operated and hyperprolactinemic as well as in chronic sham-operated animals was one of inhibition, while in the chronic hyperprolactinemic animal, the application of LH-RH initiated excitation rather than inhibition. These results provide evidence that chronic (long-term) exposure to elevated prolactin levels is a sufficient stimulus to modify the neuronal response pattern of VMH nerve cells to iontophoretically applied LH-RH but not to prolactin nor to DA.

Sensitivity of hyperthermia-treated human cells to killing by ultraviolet or gamma radiation

Human xeroderma pigmentosum (XP) or Fanconi anemia (FA) fibroblasts displayed shouldered 45 degrees C heat survival curves not significantly different from normal fibroblasts, a result similar to that previously found for ataxia telangiectasia (AT) cells, indicating heat resistance is not linked to either uv or low-LET ionizing radiation resistance. Hyperthermia (45 degrees C) sensitized normal and XP fibroblasts to killing by gamma radiation but failed to sensitize the cells to the lethal effects of 254 nm uv radiation. Thermal inhibition of repair of ionizing radiation lesions but not uv-induced lesions appears to contribute synergistically to cell death. The thermal enhancement ratio (TER) for the synergistic interaction of hyperthermia (45 degrees C, 30 min) and gamma radiation was significantly lower in one FA and two strains (TER = 1.7-1.8) than that reported previously for three normal strains (TER = 2.5-3.0). These XP and FA strains may be more gamma sensitive than normal human fibroblasts. Since hyperthermia treatment only slightly increases the gamma-radiation sensitivity of ataxia telangiectasia (AT) fibroblasts compared to normal strains, it is possible that the degree of thermal enhancement attainable reflects the genetically inherent ionizing radiation repair capacity of the cells. The data indicate that both repair inhibition and particular lesion types are required for lethal synergism between heat and radiation. We therefore postulate that the transient thermal inhibition of repair results in the conversion of gamma-induced lesions to irrepairable lethal damage, while uv-type damage can remain unaltered during this period.

Hormonal modulation of the responsiveness of midbrain central gray neurons to LH-RH

The spontaneous firing rate of midbrain central gray (MCG) neurons and the effect of iontophoretically applied prolactin and luteinizing hormone releasing hormone (LH-RH) on the electrical activity of these neurons was studied in untreated and estrogen-progesterone-treated ovariectomized female rats. The spontaneous firing rate of MCG neurons as well as the neuronal membrane responsiveness to iontophoretically applied prolactin was unaffected by the presence or absence of ovarian hormones. In both treated and untreated rats, the majority of neurons were not responsive to prolactin. On the other hand, the responsiveness of MCG neurons to iontophoretically applied LH-RH was influenced by hormonal treatment. A significantly larger number of MCG neurons were inhibited by LH-RH in hormone-treated animals than in untreated rats. The present work provides evidence at the electrophysiological level that ovarian hormones do not affect the firing rate of MCG neurons but do modulate the responsiveness of MCG neurons to LH-RH.

Comparison of the transcriptional properties of the Friend and Moloney retrovirus long terminal repeats: importance of tandem duplications and of the core enhancer sequence

The effects of sequence differences within the long terminal repeats (LTRs) of various murine retroviruses on transcription are examined by linking genetically engineered recombinant LTRs to the protein coding region of the herpes simplex virus thymidine kinase (TK) gene and assaying TK expression in tissue culture fibroblasts. The Goldberg/Hogness box region and the enhancer region are examined independently. We find that the Friend and Moloney Goldberg/Hogness boxes (TATAAAA and AATAAAA, respectively) give similar results in this assay, whereas differences between the sequences in the enhancer region have a marked effect. Tandem duplications increase the transcription level of the LTR. A single nucleotide transition in the core enhancer sequence has as large an effect on transcription as the presence of a tandem duplication: thymidine in the fifth position of the core enhancer (TCTGTGGTAAG) leads to a much higher transcriptional activity than cytidine. The LTRs have been implicated by others in the oncogenic potential of murine retroviruses, which is perhaps dependent on the transcriptional properties endowed in part by the core enhancer and tandem duplications.

Analysis of cDNA clones specific for human T cells and the alpha and beta chains of the T-cell receptor heterodimer from a human T-cell line

We report the isolation and characterization of 19 classes of nonrearranging T cell-specific cDNA clones and two cDNA clones encoding the alpha and beta chains of the T-cell antigen receptor from a human T-cell line, Jurkat. Results indicate that the human alpha-chain gene, like its beta-chain counterpart, undergoes somatic rearrangement in T cells. In addition, it shows sequence homology to its beta-chain counterpart and immunoglobulin, indicating that the human alpha chain is also a member of the immunoglobulin supergene family. Sequence comparison suggests that the alpha chain also may be composed of variable (V), diversity (D), joining (J), and constant (C) region gene segments. The protein deduced from the cDNA sequence has a molecular weight of 29,995 and possesses six potential N-glycosylation sites. The availability of alpha- and beta-chain genes of the T-cell receptor from the same T-cell line provides tools to study their possible roles in recognition of antigens and major histocompatibility complex products by the human T-cell receptor.