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Describes an effort to institutionalize service learning within the academic departments of the University of Utah. A community service center at the university, through its faculty advisory committee, developed campus-wide support for incorporating service learning into the core offerings of 14 academic units. Models developed by the academic units are presented, with key elements for successful program integration. (Author/MSE)

Glucocorticoids paradoxically exert both stimulatory and inhibitory effects on the proliferation of cultured rat hepatocytes. We studied the effects of dexamethasone, a synthetic glucocorticoid, on the proliferation of cultured rat hepatocytes. The timing of growth factor addition modified the action of high-dose dexamethasone ([10.sup.-6] M) on DNA synthesis. When we added transforming growth factor-[alpha] at the time of plating, [10.sup.-6] M dexamethasone weakly stimulated DNA synthesis by 26% relative to cells cultured in dexamethasone-free media. When we delayed growth factor addition until 24-48 h after plating, [10.sup.-6] M dexamethasone inhibited DNA synthesis by 50%. Using immunological methods, we analyzed the expression and signaling patterns of the ErbB kinases in dexamethasone-treated cells. High-dose dexamethasone stabilized the expression of epidermal growth factor receptor (EGFr) and ErbB3, and it suppressed the de novo expression of ErbB2 that occurs during the third and fourth day of culture in [10.sup.-8] M dexamethasone. High-dose dexamethasone by 72 h suppressed basal and EGF-associated phosphorylation of ERK and Akt. The reduction in ERK1/2 phosphorylation correlated with suppression of a culture-dependent increase in Son-of sevenless 1 (Sosl) and ERK1/2 expression. High-dose dexamethasone in hepatocytes stabilized or upregulated several inhibitory effectors of EGFr/ErbB2 and ERK, including receptor-associated late transducer (RALT) and MKP-1, respectively. Thus [10.sup.-6] M dexamethasone exerts a time-dependent and redundant inhibitory effect on EGFr-mediated proliferative signaling in hepatocytes, targeting not only the ErbB proteins but also their various positive and negative effectors. liver; EGF; TGF-[alpha]; cell culture