The development of psychotic disorders in adolescence: a potential role for hormones

This article is part of a Special Issue "Puberty and Adolescence". The notion that adolescence is characterized by dramatic changes in behavior, and often by emotional upheaval, is widespread and longstanding in popular western culture. In recent decades, this notion has gained increasing support from empirical research showing that the peri- and post-pubertal developmental stages are associated with a significant rise in the rate of psychiatric symptoms and syndromes. As a result, interest in adolescent development has burgeoned among researchers focused on the origins of schizophrenia and other psychotic disorders. Two factors have fueled this trend: 1) increasing evidence from longitudinal research that adolescence is the modal period for the emergence of "prodromal" manifestations, or precursors of psychotic symptoms, and 2) the rapidly accumulating scientific findings on brain structural and functional changes occurring during adolescence and young adulthood. Further, gonadal and adrenal hormones are beginning to play a more prominent role in conceptualizations of adolescent brain development, as well as in the origins of psychiatric symptoms during this period (Walker and Bollini, 2002; Walker et al., 2008). In this paper, we begin by providing an overview of the nature and course of psychotic disorders during adolescence/young adulthood. We then turn to the role of hormones in modulating normal brain development, and the potential role they might play in the abnormal brain changes that characterize youth at clinical high-risk (CHR) for psychosis. The activational and organizational effects of hormones are explored, with a focus on how hormone-induced changes might be linked with neuropathological processes in the emergence of psychosis.

Stimulation of pig lymphocytes with anti-immunoglobulin serum and mitogens

Mitogenic stimulation of pig lymphocytes by anti-immunoglobulin serum and by Con A, PHA, PWM and LPS has been measured by 3H-thymidine incorporation. Lymphocytes from blood, spleen and lymph node were readily stimulated by antiglobulin. Specific anti-micron serum was mitogenic for blood lymphocytes, indicating that those B cells with surface IgM can be stimulated by complexing of this surface component with antibody. An initial 2-hour incubation with anti-Ig was as effective as continuous incubation. Differentiation of stimulated cells into high rate synthesising plasmablasts was not observed. Pig blood lymphocytes were reactive to Con A, PHA, PWM and LPS. LPS was also tested against spleen and lymph node cells, which were responsive to this mitogen.