Figure 4.

The absence of GHR diminishes the salutary effect of conditioned medium from SVC macrophages on the differentiation of 3T3-L1 preadipocytes. A, Expression of GHR in GHRMacD [Ghr^{Δ/fl; LysM-cre (pos)}] and control [Ghr^{Δ/fl; LysM-cre (neg)}] mice. RNA was extracted from liver or splenocytes isolated from GHRMacD and control mice and steady-state abundance of GHR mRNA measured by TaqMan RT-PCR. Expression of the housekeeping gene GAPDH was used as an internal control to normalize results. The results (n = 3) are depicted as mean ± sem. The relative amount of the transcript is depicted relative to the expression in the control mice. B, The effect of conditioned medium from SVC macrophages on the differentiation of 3T3-L1 preadipocytes. 3T3-L1 cells were incubated with normal culture medium or conditioned medium from either bone marrow-derived macrophages (CM-Mac-BM) or SVC macrophages (CM-Mac-SVC) isolated from either GHRMacD [Ghr^{Δ/fl; LysM-cre (pos)}] or control [Ghr^{Δ/fl; LysM-cre (neg)}] mice. Differentiation of adipocytes was monitored by Oil Red O staining 8 d after differentiation. The results are representative of results obtained with two separate isolations of SVC macrophages from the respective mouse models. NS, Not significant.