Altered genetic response to beta-adrenergic receptor activation in late passage C6 glioma cells.

Previous studies have demonstrated variability in the phenotype of rat C6 glioma cells. In the present study, we compared morphology, growth rate, and beta-adrenergic regulation of gene expression in early (P39-47) and late (P55-90) passage C6 cells. Morphological changes were observed in five independently derived, late passage populations. In four of the five, the untreated cells were more polygonal than the fibroblast-like parental cells, and only a small fraction exhibited process outgrowth after dbcAMP treatment. Untreated cells from the fifth late passage population had longer cytoplasmic processes than parental cells and responded to dbcAMP with further process outgrowth. All late passage populations had shorter generation times than the parental cells. In early passage cells, treatment with the beta-adrenergic agonist, isoproterenol (IPR), resulted in an increase in c-fos mRNA and a decrease in c-jun mRNA (Gu-bits RM, Yu H: J Neurosci Res, 30:625-630, 1991). Both of these immediate early gene responses were irreversibly lost between P50 and P55. Additional differences in basal or IPR-induced mRNA levels were observed for beta-APP, GFAP, NGF, and PPE, but not for a number of other mRNAs. These results are discussed in relationship to previously described differences in the ability of early and late passage C6 cells to accumulate cAMP (Mallorga P, et al.: Biochim Biophys Acta 678:221-229, 1981).     

Antipeptide antibodies against the 5-HT1A receptor.

The availability of the primary amino acid sequence for a large number of molecules provides a fruitful opportunity for their cellular localization by utilizing the procedure of antipeptide antibody formation. This procedure permits a synthetic peptide sequence to be attached to a carrier molecule for the purpose of inoculating an animal to raise specific antibodies against the selected protein sequence. In this report we describe a number of steps that can be taken to increase the likelihood that the selected peptide sequence will be specific and antigenic. In addition, we describe how the peptides are synthesized, purified and coupled to keyhold limpet hemocyanin. The preparation of the antibody and its characterization are also presented in this method report. The immunocytochemical staining at both the light and ultrastructural level with serotonin (5-HT1A) receptor antipeptide antibodies is discussed. The advantages and disadvantages of this procedure are summarized.     

Attitudes towards mental illness: testing the contact hypothesis among Chinese student nurses in Hong Kong

This study investigated whether previous contact with mental illness affected the attitudes to mental illness (AMI) of general student nurses in Hong Kong — the contact hypothesis. We employed a quasi-experimental design. We compared the attitudes to mental illness of students who had previous contact with mental illness through having taken a psychiatric secondment with those who had not taken a psychiatric secondment. Also, we compared the AMI of: students who had taken other courses related to mental illness with those who had not; those who had a family history of mental illness with those who had not; and those who lived with a mentally ill relative with those who did not. We found that previous contact with mental illness had no significant effect on the attitudes to mental illness of the students. In other words our findings do not support the contact hypothesis. Our sample expressed positive general attitudes to mental illness when presented with general issues about mental illness. However, their attitudes were less positive when presented with specific issues about mental illness that might impinge upon their daily lives. We discuss the implications of these findings for mental health nursing practice, education and research.